# Welding 101 and 102



## dragonsgate (May 19, 2012)

mizlplix said:


> *Any welding process is dependent on the joint design, fit up quality and cleanliness. *Take your time, do it right. (sticking in a piece of rebar or an old bolt as a spacer or filler is a silly/ childish practice. "Just say no!")
> Unfortunately, I see a lot of sad, childish things on even nice cars. It puts the whole thing into question as to quality and safety. It does not represent the EV community very well either.
> (End of part one)


Gees it’s barely light here. What are you doing up so early? Looking forward to reading more of your welding course. As for bolts as filler it is a good thing to avoid doing. Lesson learned from experience many years ago. However I have seen a couple of unique examples of the practice. How the public sees my Ev is a major concern so I try to make everything as right as possible.


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## kennybobby (Aug 10, 2012)

Thank you for a great overview, looking forward to your part two, etc...


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## mizlplix (May 1, 2011)

When I first learned to arc weld, they made me use bare 1/8" diameter wire, 10" long. After I got to where I could keep an arc going the whole rod, I got introduced to rod coatings.

I was told to take that bare wire and roll it in mud. When dry, I was to weld with it......Surprise! It was a LOT easier to hold a stable arc and the bead looked a ton better.

Next, I was told to wet a piece of notebook paper and roll it tightly around a bare piece of wire. Even better! I could easily weld a 2" long bead that looked like something. Maybe there IS something with coatings...

Today, most AC electrodes are coated with a paper based flux. They have added some things to cut down smoke and to provide an oxygen omitting shield from the molten weld puddle.

DC electrodes have very complex coatings. They are used for many, many different welding processes. 

Oxygen. Time to talk about oxygen.... It may be necessary for life on this planet, but it is harmful to any heat related form of welding. Most welding attempts to omit oxygen. If you have ever tried to weld in the wind, You have seen the effects of oxygen on a molten weld puddle.

Hydrogen. That too.... Hydrogen causes unwanted alloying of weld metals during weld deposition and during the critical cooling stages. Many have heard of "Hydrogen embrittlement". It causes uneven alloying in the matrix, which leads to stress cracking and eventual failed welds.

Nitrogen. It is our friend. It is inert, as is Argon and several other gasses.

Co2. It works well on ferric metals, but leads to weld area contamination when used in aluminum welding and others.

Lets start with "stick" welding:

Your first welding project on your soon-to-be EV is those dreaded battery boxes. (Do not start with the motor mounts.....unless you can already weld). No matter what materials you choose, your design is very important to the success of this endevour. 

Lap joints are best for both welding ease as well as joint strength, they are easiest for an unskilled operator although they are sometimes awkward in application. The weld can be placed in tension or compression. A tension weld strength is subject to the skill of the operator. The compression weld, however, is not. Even a poorly done compression weld can be extremely strong. Use them when ever possible.








http://www.jflf.org/pdfs/papers/design_file301.pdf



Which leads us to butt welds. They are more difficult for an unskilled operator. There are several types, but lets stick to two kinds: plain butt (with and without a gap) and beveled (single and double). 

The plain butt joint is a crude affair that depends on the operator maintaining even weld penetration to both work pieces. It can not be ground flat without some loss of strength.










The bevel joint is more difficult to perform because the material is thinner, but will provide a more superior finished joint. It can be successfully grinder dressed flat without diminishing the weld strength.










Any single sided weld can be made immensely stronger by simply placing a small tack weld on the opposite side to prevent weld root under-bead cracking due to weldment flexing. 

Mistake #1: It is easier to weld if the current is turned down to the lowest level. Not so. A minimum current level is necessary for adequate penetration and welding arc stabilization. 

Mistake #2: It is easier to weld if I hold the arc length longer. No. The proper arc length is really very short and must be held. It will prevent voltage loss and help keep contaminants out of the molten puddle.

Mistake #3: I want to travel fast to get this over and not burn through....NO! If you have the current set correctly for the material thickness and the correct diameter electrode selected, you will have less chance of burning through. ALL arc welding depends on a thorough heating of the metal, almost burning through....You are going to be on the edge all the time. Get used to it. By dragging the electrode too fast, you actually aggravate the situation by melting out the area, but not staying around to fill it back in again...

Always drag the electrode like a match to start the arc. Do not tap it. Tapping is an advanced technique and takes some time to master.

After starting the arc, the first thing you need to do is to form the molten puddle. After the arc is started, immediately go over to the start of the weld area. Get your close arc gap distance started and then go around in meduim-fast small circles to form the puddle. After you have this to your liking, proceed with the weld.

The weld ending is the same. Stop advancing a little short and do that circling thing again. Break the arc when there is a full, nice ending puddle.
This does several things...But mostly it forms two round contoured ends that resist crack formation. Very important. Practice this!

The direction you point the electrode is the direction of the most heating. This is most useful in welding a thick piece to a thinner one. Simply point the electrode more towards the thicker piece and gently let the weld metal roll up against the thinner one. It will take some experience to tell how much to bias the arc to get an even weld penetration, but stick with it.

(end of part 3, more tonite)


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## dragonsgate (May 19, 2012)

I took some welding classes at a local Jr. Collage when I first got out of the service in the 70’s and the instructor was an old Air Force welder. He insisted that we get our faces close to our work so we could see what we were doing. I know this is easy on the bench but all the technique in the world will not help if you can’t see what you are doing. So a good mask and the right lenses are a must.


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## dladd (Jun 1, 2011)

I took two semesters of welding waaaay back in college. My mom still uses the bookends I made out of 1/4" plate. 

I'm reading with interest, I've been wanting to buy a small mig welder to re-learn and do some small scale projects. Interested to see what you suggest as a good starter setup (hint, hint).

For important stuff (like my motor mounts), I take it down to the local muffler shop and hand the guy a $20, hard to beat that.


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## poprock (Apr 29, 2010)

thank you for passing on your expertise. It is written in layman's language and is easy to apply. MIG welding next?


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## GizmoEV (Nov 28, 2009)

Thank you. I'm looking forward to the next lesson.


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## Salty9 (Jul 13, 2009)

Could this thread be moved to the Wiki so it wouldn't evaporate down the line? Also start a Wiki links thread in the Tech section with hot links referencing the Wiki topics.


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## mizlplix (May 1, 2011)

SMAW (Stick Metallic Arc Welding) as it's known by the AWS (American Welding Society).

It is more than a work process. It is an art. It is learned by many, but really mastered by relatively few. It requires practice. A lot of practice to make a workman like weld. It also requires a feel and intuition to make really beautiful welds.

When I first started welding, no one came to me and said "Do not breath the smoke." It is bad for you. It may not be immediately fatal, but it will gradually accumulate toxins in your body and later in life, you will suffer the consequences. 

"When oxygen combines with anything in an uncontrolled reaction, the resulting product is unpredictable." Truth. Simply take a big snort of any smoke produced by a fire (campfire, brush fire, rubbish fire....Etc) and you will start coughing, hacking and blowing snot for a long time, until it gets worked out of your system. It is your body telling you "What were you thinking?" Listen to your self, wear a respirator, hold your breath or stand up wind when welding. ALWAYS! The same for grinding or sanding on any metal, it adds to your metal toxicity (like everything else) which is accumulative over your lifetime and eventually settles in and kills your organs. (Have a nice day)

Most stick welding jobs start with choosing the proper type of electrode. Fortunately we invented written language and the "rod" boxes are printed with instructions stating it's best usage. We most generally learn welding with mild steel,(also known as A36 or 2018 regular carbon steel). It has good, stable, linear properties that enable reproducible results. (easy to learn on) We can branch out to other metals later.

6010 & 6011 are the standard, all position, rods for every day welding on mild steel. They have the same 60,000PSI rating of mild steel. They have a paper based flux coating and form solid, strong welds that can equal the strength of the parent material. But, they require skill and practice to form a nice looking weld. 

6013 is an easier rod to use by the learner. It is for flat welding only and forms strong, decent looking beads with less practice. It is also a 60,000PSI rod. 

7018 & 9018 are two alloy rods that have potentially a greater strength over the parent, base metal as the 70,000PSI and 90,000PSI ratings suggest. They are both all position usable and form beautiful, strong welds that are repeatable and in their finished form, require no grinding what so ever (If done properly.....)

While we are on the subject of grinding, I want to go off on a minor rant....LOL. The hall mark of a professional welder is the formation of good looking weld beads with little clean up and NO grinding involved. When someone says they "can weld", I simply look at their work. I look for grinder marks. I look for weld bead consistency. I look for well thought out joints.
Lighten up on the grinding, OK? You only need to hit the knobs, the splatter, the rod tracks left by dragging it to start, the wide places and the humps. Leave the rest alone. After painted, it will look a lot better than a hacked-up, over ground piece of work. 

OK, I'm back now...

Always pick an electrode that is the thickness of the work piece or maybe a size smaller. I always go 1 size smaller. It makes life easier, better looking welds and easier to see around...

Which leads to vision. Yes, I could make flawless, perfect welds, time after time, when I was 18 years old. It was something I took for granted. Time is truly the great equalizer in that we all suffer a gradual degeneration of all systems, coordination and sight included. I use glasses or a "cheater" lens in my helmet (hood). I also have a Harbor Freight, auto-darkening helmet. $49,00 on sale. Get one. No excuses. It is wonderful for starting and positioning yourself for the start of the weld.

Wear cotton clothing. Not blended, 100% cotton. You will figure out the reason for this eventually...LOL Wear gloves. NOT those monstrosities they sell as "welding gloves" in the stores either....Get a leather pair that are comfortable, pliable and medium thick, not heavy. No cloth shoes. Leather only, without laces or cover the laces with several layers of duct tape. You will need long pants and a long sleeve shirt also( cover the top pocket openings with duct tape....you will also figure this out.....

There is no substitute for burning electrodes (practice). Get yourself a piece of steel. 3" X 3" X 1/4" minimum. Find yourself a place to be comfortable. Sitting, Standing Kneeling does not matter. Be comfortable....

(End of part 3)


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## mizlplix (May 1, 2011)

So, we have the proper clothing, flip flops, shorts, sun glasses and a tank top. Cool, You need to be drinking beer also.....It will help with all the little burns and the second degree skin covering you will have in about 10 minutes.

Seriously, I was not always careful, I sometimes took chances, I have uncounted burns everywhere. I can tell you what I was doing and when every one happened too. As with most welders, burns and I are old friends. Get used to it, it will happen, but you can minimize it.

Lets look at your welder. SO, You bought that little red box from Home Depot. The one that was "on sale". OK, so we try that. 

The most common first mistake with beginners is that they let cost dictate what they buy. As with most things, the better items cost more. Your little welder can weld....If done by an experienced person, it can perform decent limited welds on most steels. 

There are three things to look for when buying a welder...type of current (AC-DC or both)maximum amperage and duty cycle. 

*Get a DC welder.* (Or AC/DC welder) AC alone will weld, but it splatters a LOT and produces an inferior weld appearance. It can be used on steels, but is necessary for aluminum alloys.(No don't try to weld aluminum at all with a stick welder. It is incredibly difficult to do, control and look like anything.)

*Get the biggest welder you can afford*. (most 120VAC welders are just a toy)

*Get one with the longest duty cycle* you can afford.

Start learning with 3/16" 6010 electrode if you have a decent DC welder. Use 6011 if you have an AC welder or a very small DC unit. (Home Depot red box)









Lets begin at the beginning: Start with your above mentioned 3" X 3" X 1/4" plate. The ground clamp does not need to be on the plate, but the plate needs grounded. It can be placed on another metal surface that has the ground clamp on it. Weld a single pass (bead) across the middle the plate.

Strike your arc like a match. Move it back over to your starting spot. Bring the rod down to within 1/8" of the plate. Do a little circle or two(the diameter of the rod-no bigger) to start a good weld puddle.The first thing you need to know is that this type of electrode (rod) needs constant movement. (movement not travel.) Movement means side to side or forwards and backwards. Try very small circles, in a sort of traveling chain, keeping that 1/8" or less distance as the rod burns off and gets shorter. 








ARC LENGTH RESULTS


Circling and moving along and keeping the short arc all the while. Continue to the end of the plate, adding another rod if necessary. Burn each rod down to the holder. DO not waste any. Sometimes you will stick one. Lay it aside and reuse it when it gets cool. You can cut it off even to make it start easier.

NOTE: I watch the width of the weld and adjust my travel speed to keep the width constant. That automatically compensates for any divots, pits or unevenness in the weld area and leaves the best looking weld.

Chip the slag off. Weld another bead besides the last one. Clean it, on and on until the plate is filled or it is too hot to weld. Dunk the plate in a bucket of water to cool it. Adjust your welding current as you see fit. You will notice it needs turned down as the plate gets hotter.....

Turn the plate around 90 Degrees and weld cross ways to the old welds. Dunking it when ever it needs it. Grind any big knobs that get into your way. 








Continue this until the plate is 1" thick.......Then throw it away.

Get a new plate. You now have a new feeling for this welding stuff. This is a new beginning too. Set your welder to the setting you have decided works best for you with this welding rod size. Start at the edge of the plate. Place the next weld beside the old one, but this time, make it take out 1/2 of the width of the old weld....Over lap them 1/2 weld width. You are now getting this down pretty well. For flat that is.......Next up verticle welds....

(End of part 4)


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## DIYguy (Sep 18, 2008)

I think Miz is doing an admirable job. 

Welding has been my life. First as a Journeyman, then as an Engineering Technologist and Engineer. I've worked in the automotive supply chain (Tier1) the whole time. I've worked on many of the platforms that most of you have driven in or own. Mercedes, Daimler-Chrysler, General Motors and Ford. My company built the frames, cross members, cradle assemblies, control arms, bumpers, body panels, SMC panels, etc for all of these companies. They don't (for the most part) build this stuff themselves. The only reason I give some background is to qualify my opinion . . . that Miz is doing an admirable job. It's easy to critique . . and done all too often on forums. 
Keep it going Miz.


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## mizlplix (May 1, 2011)

So, we can now hold a fairly uniform bead and keep the width constant while moving along slowly, getting decent penetration, moving in little circles, covering both halves of the root crack....every time. We are developing the "eye" for watching all those conditions at once. Nice work! Search you tube for examples.

The welding current can be adjusted to achieve almost any weld deposition, penetration or surface smoothness. We pick out the electrode (rod) to suit the material type. The diameter to match the material thickness, The current amperage to suit the penetration we want, The current voltage for the surface finish and the rate of travel sets the amount of weld metal deposition. Simple (once you start thinking about it that way)

By now you have figured out that the way you hold the rod will affect the weld tremendously. 








This is called the "drag" position, where the rod is pointed back towards the weld puddle.


Now learn to do it right-to-left AND left-to-right. Then with the right hand then the left hand, both. (Optional for a DIY, but required for a "good" welder)

Once in a while, you will experience an intermittent problem. You are welding along and suddenly small blobs of molten metal start flying out of the arc and not sticking where they should. No matter what you do, it just digs a hole and fails to fill back in. This is called "Arc Blow". It is an adverse magnetic effect. It is caused by the magnetic flux of the parent metal running the wrong way to promote the weld you want. STOP. Reposition your ground clamp. This sometimes works. Failing that, reverse your welding direction. That usually always stops it. (You DID practice welding in different directions?)

The next thing you will find out, is that in the real world, we can not always turn our car on it's side or upside down to enable us to weld in the flat position. That leads us to out-of-position welding.
*Horizontal welding*,*Verticle plane up and down progression welding* and* overhead upside down welding*, 








Each has it's own special quirks but is mastered just like flat welding was, Practice.

Overhead (upside down) welding is exactly like flat welding. Really....The molten weld puddle will stay in place due to the force of the arc, magnetic flux in the metal plate and the fast cooling of the metal. (called freezing) If you are having the metal fall out, you are either travelling too fast or holding too long of an arc length. The welding current is set almost the same as flat welding or slightly less amperage. (Remember tiny little circles)

Downwards progression is used for a "seal weld" or in a low deposition rate situation where a thin weld is desired. If it is not thick enough, allow it to cool some and do it again. It uses a simple straight drag technique. 

Upwards progression is harder. Some people never master this one. In this position, you start the arc, form the puddle....... and thats where it all changes. The weld puddle will run out down the plate if you continue. It needs a "cooling" cycle before any more is added. Move the rod quickly upwards at least two rod diameters and then go back down again and form a new puddle. Move back upwards again, then back down to form another.....on and on until you are at the top of your plate. This is best practiced on a "VEE" plate weldment.








It should look like a stack of dimes.........

This leaves us the dreaded horizontal weld. Th is done like flat except I use a "J" pattern instead of those little circles. Back and forth, back and forth, moving about two rod diameters out and back in with a little upwards flourish.


That is a decent over view of the 60XX series welding electrodes.


Next: the 70XX series electrodes(Yes they are very different.)

(End of part 5)


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## mizlplix (May 1, 2011)

So, by now, we have holes in our socks, breaking shoestrings and sun burned eye lids......from tack welding without a helmet.

The 70XX, 80XX, 90XX and 110XX series electrodes are called the "low hydrogen" series because they all have flux that helps to occlude or diminish hydrogen in the weld area. It allows for a slightly higher tensile and ductile serength over A36 regular carbon steels.

It welds with less splatter and the welds clean up easily compared to the 60XX series rods.







7018 WEAVE (Average talent)









6011 WEAVE (average talent)

3/16" diameter, E7018 electrodes are my favorite choice when welding vehicle related things. It does require a fairly clean environment. It does not like rust, paint or oils. You can weld with both a stringer or weave (wash) bead.
















The only reason I ever use a 60XX series electrode is when the material is painted or rusted and I can not clean it well. Otherwise it is LH7018 or my MIG welder every time.



If I were just learning to arc weld, I would learn to M.I.G. (Micro-Wire Inert Gas) weld first. It is more intuitive and (I feel) more quickly learned than stick welding. It automatically holds the critical arc length gap, It is easier to start, you do not have to learn to keep compensating for the ever-shortning electrode and you never have to stop in the middle of a weld because you ran out of rod.







MIG WEAVE (average talent)









I would never recommend buying a MIG welder under 100 Amps. My MIG welder is a 325 Amp Hobart unit...A little overkill-Yes, but I have had it over 25 years and it was used when I bought it. Try that with a Harbor Freight special...

The other important issue when selecting a MIG welder is the duty cycle.

Most light duty welders may have a 180 amp rating but it also has a 30% duty cycle. This means that you can weld 3 minutes, then you must wait 7 minutes before welding again or risk overheating the main transformer. 

Try to get at least a 50% duty cycle and over 100 Amps, the larger, the better. (Mine is 350 Amps AND a 100% duty cycle). 

I also recommend a smaller diameter wire for the home DIY welder. Mine is a .030" size and it is a little too big for sheet metal. A .024" size would be great for sheet metal and still be able to weld 3/8" thick steels. (More with pre-heat).

(End of part 6)


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## mizlplix (May 1, 2011)

So, everyone has been reading this thread as a necessary evil, waiting for the MIG section.......Maybe you learned something anyways. Most basic welding practices still apply in MIG welding too.


One of the most basic problems with any arc welding is a poor ground connection. It causes local super-heating of the clamp, deterioration of the cable and erratic welding conditions that will have you pulling your hair out.

Secure the ground cable to your work piece. I welded a 1/2" x 2" bolt to a good 4" C-clamp and bolted it to my ground cable. It is cheaper and better than most of the crap they sell. If you have a fab table, make a permanent ground cable to it, and leave it alone. Localized heating in any electric cable is simply a loose connection....fix it!

Wire, I have recommended a .030"-.024" size for DIY use. I still stick by that. It will allow you to weld 20ga sheet metal up to 1/2" plate with ease. 

Also...I do not recommend long gun cables. Sure they are handy at times, but with age, they become a sticking mess. Use the shortest length you can get by with.

Brand...I do not have a favorite brand. I have used everything under the sun. Most were nice when new, but after a capacitor or internal connection gets loose, they are all a headache until fixed.

Every roll of wire, blow 100 PSI air through the gun cable before loading the new roll. The stores have little felt pads that clip to the wire just before the drive rollers to lubricate the wire inside the gun whip. 

Think about it....The wire acts like a mini chain saw cutting through the inside of the gun cable. It leaves a groove in the coil spring like liner. In time, the wire will start hanging up causing the wire to feed erratically. Once per year, pull the liner and rotate it before pushing it back in. Maintenance....

I do not use expensive MIG Mixes gasses. I use plain old CO2. Mig Mix is in the compressed gas state. CO2 is in the liquid state....there is more in the tank per filling, and it is 1/3rd the cost of mixed gas. I use 2 tanks of mig mix per 50# roll of wire. I can use 2 50# rolls of wire to one tank of CO2 gas.

Economics. But there is another factor too.

Mig Mix makes a nicer weld, with less clean up.

CO2 leaves a slightly rougher weld surface, But I weld better with it than most do with Mig Mix. Co2 also lets the arc gouge into the metal deeper giving greater penetration than Mix. Pure Argon will hardly penetrate at all and welds great on thin sheet metals with no burn through.

(End of part 7) Next: some MIG basics and some tricks.


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## TomA (Mar 26, 2009)

Thanks so much for the primer, Miz. Good stuff here, no matter what the skill level one comes to it with.

I'm always incensed when I see on the various hot/rat/bike/race/rod builder's TV shows guys tack welding with bare hands and no face or eye protection. What does that say to the average young guy with no trade school or shop courses in high school to fall back on? You might just as well show professional athletes on TV shooting up steroids and pain killers. <end rant>

There are so many ways to learn how NOT to do things. Thanks for a channel of pure, reliable signal here...


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## JRoque (Mar 9, 2010)

Wow, impressive series. I finally understand what the stupid +/- button does on my welder! Great stuff.

Hopefully we can cut our comments and pin Miz's articles to the Wiki. Looking forward to the MIG section next.

JR


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## aeroscott (Jan 5, 2008)

One of migs biggest weakness is lack of penetration .CO2 is a great way to solve this weakness , as stated before . The other important thing to remember is voltage is very important , mig or short arcing is at a lower end of the voltage range , spray arcing is at the high end voltage ( same equipment) but you lose the fast freeze of the weld . The amps are controlled by wire speed . If you increase the stick out , you increase resistance , preheating the wire and killing amps . This is a trick used if the weld is getting hot and/or a gap needs filling .very tricky .


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## DIYguy (Sep 18, 2008)

For what it's worth, MIG is actually a non-standard term meaning Metal Inert Gas. Everyone uses it so they know what they mean. When CO2 or mixes with CO2 are used it is actually MAG meaning Metal Active Gas. Proper term for the whole family including flux core etc is GMAW or Gas Metal Arc Welding. As mentioned, CO2 tends to increase penetration when mixed with Argon as it is oxidizing. It can add some embrittlement in certain cases also. Typical mixtures are 75/25 Ar/CO2 90/10 or 92/8. For pulsing or pure spray you need a minimum of about 90% Argon to support it. 75/25 is a good all around mix and will give decent penetration and less spatter for the average job.


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## mizlplix (May 1, 2011)

What he said....LOL, I actually tried to stay away from anything too technical this early in the thread.

But He is correct in everything he said.

Including Aero's spot about increasing wire stick out killing volts and helping to fill in a large gap. You can get silly about it and draw back to where you are blowing chunks of wire to bridge the huge gap, Then follow up over it with a heavy weave pass of weld. Then flip it over to grind out all of that wire/splatter and weld it in from the back side to make a 100% solid weld out of a fab mistake.

More of those tricks later.

Wire welding, cored or micro wire, needs clean metal. Can you weld dirty stuff? Sure. It depends on what you call "Weld". 

Dirt, oil, paint or rust will burn with the arc and produce unwanted alloying elements with unpredictable results. (OK, predictable in the case that they will all be flawed) Porosity, inclusions, rough contour and lack of fusion can result.

It is OK to tack weld dirty stuff, just clean and prep the piece before finish welding (including grinding down your tack welds smaller).

Welding with cored or solid wire is just like stick welding except you can carry a small stripe of weld to a lot of metal in one pass. The real trick is to do it in a workman like manner. No edge under cuts, no middle over builds, no wide then narrow spots, no highs , no lows. Consistency..... Repeat-ability.

The key to being a good welder is to be able to see what you are doing. I can weld left to right, right to left, towards me and away from me, right and left handed-all look the same. I hold my eyes very close to the work piece and weld towards myself when ever possible. That way I can see the edge penetration and center fill.

Get into a comfortable position. Never even start a weld if it is awkward. Your work will look like crap because you will hurry to just get it over with.

The welding arc light is not your enemy. The Ultra violet radiation is. Your eyes will recover from the bright light, but it will be incrementally damaged by the UV rays. Protect your eyes. If you are fitting up for a welder, wear wrap around glasses at least. Any exposed skin will burn. Ankles, eye lids, tops of feet, throat. Cover them all even if you use duct tape.

One of the side effects of welding is heat warp age of the work piece. Minimize it by tacking the pieces before welding solid and also clamping the pieces when ever possible. When welding two sides of anything, tack it together,( both sides). Then look at it. Which way do I want it to warp? (You can use this warpage to actually help keep the work piece straighter). 

*Remember:* The first weld you make will shrink more than the second weld will. Weld first on the side that is convex, it will draw back towards straight. Then weld the second side, it will not pull at all.

Wire welding is the preferred method of most shops where there is no wind. Where wind is blowing, cored wire is king.

You start your weld like a stick weld, back from the edge some. Make your puddle by forming little circles then after you have enough metal, the last circle is bigger and washes metal just up to the edge of your plate, very quickly go back to the puddle and continue the weld. At the end, do a similar thing, stop short of the edge and do two small circles and the last washes metal over to the edge. Break the arc back at the puddle, NOT the edge. It leaves a nice square corner and stops bead cracking caused by the voltage drop of stopping the current. This is for flat and overhead welds both.

There are many guide lines for weld width, many formulas depending on material and wire size. I usually weld as wide as necessary to do my job. If the work piece is 1" thick and has a 45 Deg. bevel, it can be as much as 2" wide when finished. That is a little too wide for one cap pass. Two weave passes are needed to cover it. I can weld a weave 3" wide and it looks good too. But, it would be not as strong as two smaller passes joining in the middle.


One thing you need to practice when wire welding: Perform all welds in one pass without stopping. If welding around a pipe or tube to a plate, go around to the back in the blind spot to start the weld. Bring it around towards yourself, around the other side to the back, twisting yourself to be able to see the old stopping place. You can make a nice ending cut off that way. Plan all welds before hand. Think quality, repeat-ability. 

(End of part 8 )


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## DIYguy (Sep 18, 2008)

mizlplix said:


> Wire welding, cored or micro wire, needs clean metal. Can you weld dirty stuff? Sure. It depends on what you call "Weld".
> 
> Dirt, oil, paint or rust will burn with the arc and produce unwanted alloying elements with unpredictable results. (OK, predictable in the case that they will all be flawed) Porosity, inclusions, rough contour and lack of fusion can result.


Of course this correct. . .however, worth mentioning is a wire class generally referred to as "Metal Core". There are a variety of them and they differentiate with the commonly referred to "Flux Core" wires in that they are not self shielding. The will however, handle much more surface contamination like light rust, oil and scale than the uncoated solid wires. 
Flux Cored wires typically generate the shielding medium (as well as potentially adding alloy to some) and this is why they are better in windy environments. . . also for some coated materials like galvanized, galvaneal, galvalume etc. 
Most people who are DIY would rather save their money and clean the material first, but I wanted to mention it because there are those who fab a fair bit of material and the overall cost includes prep and clean-up. In some cases, metal core wires can save a considerable amount of time/money. They are used with typical gas shield mixes as discussed earlier. They leave no slag and little to no spatter, depending on gas mix. They also tend to be better at bridging gaps.


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## mizlplix (May 1, 2011)

Good morning everyone!

"After 60 years old, you always know when you are having a good day. You wake up...."


I am used to teaching in a classroom/shop setting where we have visual and hands on opportunities. I will do my best to describe things, we otherwise demo.

Most of the things I described in the stick welding part still apply to M.I.G. welding.


A weld is a relatively simple process where you join two pieces of similar or dissimilar metal by melting the dividing line to a depth and allowing the resultant "puddle" to re-solidify into a solid mass connecting the two.

*Welding is all about heat control*. (remember this)

It can be done by gaseous or electric heating. The principles are the same.

In a simple butt weld connection,
















Most welds on material greater than 1/4" in thickness are beveled(Top pic)
The bottom pic is a common butted weld.

The depth of fusion is controlled by the heat applied. Your movement speed mostly controls the rate of buildup. (it can be argued that speed controls fusion depth too, but that is because it allows more heat in that spot... Heat)


There are problems with both over and under heating. It must be in that "sweet spot" for every weld you make.

Under heating will not give the penetration and fusion necessary. Overheating will quickly ruin the metal by oxidizing it (Burning it).

When welding multiple pass welds, it is crucial to place the beads correctly to maintain adequate fusion. 

















Notice how the 3 passes are carefully overlapped.









An extreme example? No. I have welded on a single joint that took almost a week to complete. We had to keep propane burners on them when we were not actively welding or at home nights.

The single largest problem encountered by a new welder is that you know when you are having trouble, but you don't know what to do about it.....

Develop a short check list for yourself.

Cables tight on the machine.
Cables tight on the gun/holder/clamp
A good ground
Gun cable is in a kink or tight bend.
No gas flow
Slow gas flow
Wind
Dirty metal
Exceeded the duty cycle of the machine.
Rust/dust on the welding wire.
Moisture in the electrodes/rods.
Someone spray painted my welding lens black.....(beer was involved)


Lets talk about materials:

Mild steel-Almost everything you use has mild steel in it. The carbon content is low, it is malleable and easy to work and form.

Add carbon and we have high carbon steel (like a gear). It is still kinda easy to work with except bending is tougher to do without damage. It welds nicely but tends to crack along the weld line at the parent metal. Why? 

During the welding (Heat and cool) process, it became (uncontrollably) heat treated. The steel became hard and the weld remained soft causing stress riser problems when loaded. It tends to gather excessive carbon at the weld line. (Like welding a gear to a shaft)

Solution: We can weld it and then re heat it to sub critical (low red) temperatures and allow to cool to anneal it back to it's normal state. 

Stainless steels: Simple. We add chromium while removing the carbon in regular steel. (simplified for sure, but basically true) The more we add chrome and remove carbon, the higher grade it becomes. The easy field test for stainless steel grade is to use a magnet on it. 

Does the magnet stick? It is a low end stainless. The less carbon-the less the magnet will stick. The really good grades of stainless steel are non-magnetic. The low end will gradually tarnish with age and the high end will be bright after even 20 years in the rain.

Can Stainless be welded with regular MIG wire? Sure, but it adds carbon to the weld and it will corrode faster than the stainless and will only have the ductility and strength of the lesser of the two metals.

When welding, other metals have their uses too.

A 1/4" thick strip of copper or brass can be used to fill a hole. Clamp or hold the brass/copper to the bottom of the hole/crack/gap to be repaired. Weld it like normal. Un-clamp and tap the brass and it will fall away leaving a nice flat, filled piece.
Aluminum can be used too but is harder to remove and causes more clean up.

When sitting down to weld, position yourself to where you can see all the way around the work piece. Like welding a plate to the end of a pipe. Always start around in the worst spot for you to reach and weld towards you. You simply follow it around and wind up at the back again where you break the arc. Leaving a continual, smooth, nicer looking weld.

There is no substitute for burning rod or wire. You literally learn every time you do a weld and that means forever. Never stop learning. Watch others weld when possible. Steal every trick you can.

(End of *basic welding *section)

Please ask about any part you would like expanded on, or I might have missed.

Does anyone want to see a basic section about gas welding or T.I.G. ?

Miz


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## Thumper (Nov 24, 2010)

Excellent tutorials!
Thanks very much for posting.

I would love to see some info on TIG welding.
I recently bought a Chinese 180A TIG/Stick/Plasma unit but I am having trouble getting the "stack of dimes".
(I know - practice, practice, practice.)


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## order99 (Sep 8, 2008)

"Does anyone want to see a basic section about gas welding or T.I.G. ?"

Absolutely! I my be stuck with using 1/8" brazing rods and map gas torch (dirt poor and no room or money for better at the moment) but that doesn't mean i'm not copying these posts to Text for use later use on down the road! I'd love to hear about your TIG and Oxy-acetylene techniques.

In fact, if you have any experience with silver, bronze and brass brazing-and still feel like discussing after Gas and TIG-i'd love to hear any advice you can supply on brazing techniques. I'm currently practicing on bits of angle iron and bicycle tubing in hopes of creating a frugal pedal-electric hybrid....quite frankly, i'm at a loss to determine when the filler is 'wicking' properly and end up slathering extra filler and drilling 'fill-holes' and probably over-engineering the connections out of paranoia. If I can't be confident in my techniques i'll probably toss the whole thing and wind up with the first EV made entirely of woven wicker and fiberglass... 

But please discuss TIG and Gas welds and complete the welding section before I divert you elsewhere.


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## njloof (Nov 21, 2011)

Any tips on plasma cutting, or is that too easy?


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## MalcolmB (Jun 10, 2008)

Miz: you're doing good, this is a big subject to tackle 

order99: If in doubt, weld up a test piece then hit it with a big hammer. If it breaks in the weld it's not good enough. Rinse and repeat. There are some really good demo videos on Youtube. I'll try to dig out a good link.


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## mizlplix (May 1, 2011)

OK, I will continue and try to post an article per day. Yes, I do have some experiences with brazing. I used it to repair Formula Ford frames that were brazed when they were made in jolly old England. (Those wacky Brits love that brass...LOL) I even had a group of guys lift one up onto 4 oil drums so I could do an emergency trackside repair...Brazing underneath/overhead is a trick, but it can be done. (but not without some casulty in burnt laundry)

Miz


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## JRP3 (Mar 7, 2008)

mizlplix said:


> Can Stainless be welded with regular MIG wire? Sure, but it adds carbon to the weld and it will corrode faster than the stainless and will only have the ductility and strength of the lesser of the two metals.


Why does my regular wire bounce off SS? Because it's gasless flux core? Tried to fix a SS exhaust pipe once and made a mess of it.


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## mizlplix (May 1, 2011)

> Can Stainless be welded with regular MIG wire? Sure,


MIG=microwire/inert gas. not flux cored. (I was referring to solid wire with a gas shield.)

Flux cored is picky in it's application. In it's smaller sizes, it is more difficult to weld with than the larger wire. (1/8") Which is a piece of cake.

I would also mention that flux cored always needs the burned end if the wire broken off and the weld area sanded clean of oxidation for easier starting.

Miz


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## mizlplix (May 1, 2011)

Today, I would like to touch on gas welding. (Oxygen/acetylene)

This is a really early form of welding. It is expensive to do to any large extent.

It is just as strong as other forms of welding except for some employing alloy filler materials. 

It is a two gas system. It heats the parent metal to form a puddle, (just like stick, wire or T.I.G.), the gap is melted together and filler is added to bring the bead up to the desired profile. The burning gas mixture provides the shield to the welding process instead of cold gas or a powdered flux.

Most times the filler material is the same as the parent, but sometimes it can be different as in welding two dissimilar metals.

Gas welding starts by hooking up or checking the existing equipment. The acetylene fittings are always a left-handed thread to prevent any mix-ups. The regulator adjustment "T" knob needs backed out fully so there is no pressure in it before the bottle valve is opened. (preventing that "POP" to the diaphragm and a blown regulator) Also at this time, check the torch valves to be in the off position.

When opening the valve, do so slowly allowing the regulator to accept the pressure gently. Immediately, close the valve and watch the high/pressure gauge reading. If it creeps down(even slowly) there is a leak in the valve seat or regulator diaphragm. Fix it before continuing or lose the expensive gas at a rapid rate.

If the pressure stayed up, continue to step two: slowly turn the "T" valve clockwise to start adding pressure to the hoses up to the torch. I have a "standard" regulator setting I have used all my life that works for me. I stop at 7 PSI on acetylene and 40 PSI on the oxygen(for cutting) and 7PSI acetylen with 15-20PSI oxygen(for welding tips). After those pressures are reached, again, shut off the bottle valves to check for hose leaks. (Fix any)

At this point, I want to talk about torch types. There are two basic Oxy/Acet torch types: a straight cutting torch and a combination torch. 

The cutting torch is made in one piece. It has two hand valves (oxy & acet) and one finger lever for the oxygen lance. 

The combination torch is has three pieces. The three pieces are -the mixing chamber (handle or body)-the cutting attachment-the welding tip. It has three hand valves and one finger lever. Two valves are on the mixing chamber and control the oxygen and acetylene when it has a welding tip attached. When the cutting attachment is installed, the oxygen valve on the mixing chamber is opened fully to supply the full oxygen flow to the cutting attachment. The third valve on the cutting attachment is to control the oxygen flow to feed the flame-(the cutting lever is fed the full flow from the first valve). It is a VERY nice set up to have as it will do everything you will need. 

After it is determined that there are no gas leaks, open the acet valve on the handle about 1/8 turn or so (It varies per torch). Light the flame. Gently turn up the acet until the flame starts pulling away from the tip, and back down a little. Then slowly open the oxygen valve (on the handle or cutting attachment depending on if you are cutting or welding) until the flame turns lighter, the opacity clears up and it forms a center "feather" in the flame. That "Feather" will start getting shorter. Stop when the "Feather" disappears. This is approximately a neutral flame.

SIDE NOTE: You can gas weld with a cutting tip, it is more difficult, but possible. 

The actual weld starts by slowly forming a weld puddle (just like stick, wire and TIG). Gently, slowly circling a small area until it comes up to the proper temperature and the puddle is formed. Then the filler rod is introduced by holding it in the flame and allowing a "drip" to roll off into the puddle. If the puddle is too cold, it will then solidify and need more heating to get the puddle back.

When the puddle is formed and that first drip has dropped, you make a first circle-loop like you did when stick or wire welding. You push the molten metal back to the edge of the work piece and then continue dropping filler and making those small circles with the torch while moving along the joint. Your heat control, material dropped, dropping rhythm and travel speed will form your weld appearance and penetration. Practice......

Gas welding is VERY similar to TIG welding. If you learn to gas weld, TIG is a snap to pick up later.

(Enough for today)


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## mk4gti (May 6, 2011)

old saying goes: A before O _or up you go_!


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## mizlplix (May 1, 2011)

We used to make some respectable "pops" by turning on a small amount of oxygen with the acetylene when first lighting....LOL

Miz


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## dragonsgate (May 19, 2012)

I was taught 5 & 10. 5psi on the acetylene and 10psi on the oxy. It has worked for me. I read somewhere that over 15 psi friction could cause acetylene to self ignite. When shutting down the air goes off first or it can flash back giving a pop. As for the pop when lighting off... I was going to teach a lady how to do metal spin casting. I spent a couple hours showing her the casting equipment and explaining the process. Then it came time to light the torch. I use a pretty good sized cutting head for my casting so when I light off I open the gas pretty wide and there is a soft pop when the striker is applied. On this particular occasion there must have been some oxygen present because it sounded like a small gun going off. It startled me so when I turned to explain what must have happened the lady was not there. My wife who was present and laughing shrugged and said she ran out. The lady had exited the studio and was standing out side when I found her. End of lessons.


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## DIYguy (Sep 18, 2008)

I want to emphasize Safety! This should be the first part of any discussion regarding particularly, oxy-fuel cutting/welding.
A couple of quick points here. For safety, flashback arrestors should be used at all times. Look them up, buy a couple and fit them to your set up just prior to your torch.
Secondly, Acetylene must not be drawn at a high rate as it is in liquid state in cylinder and can actually draw off liquid if drawing to fast. 7 psi is typical, 14 or so is max. (again it's flow that's important)
For oxygen pressure, most ppl do use upwards of 40psi. This is dependant on size of cutting tip and lower pressures can work if you have a smaller tip on a cutting attachment as opposed to a large cutting torch.
Finally, and likely the most important of all is the mention of oil and oxygen. They don't mix. In fact if you look at your regulator it likely says "Use No Oil". In fact it is so important, that this message is used on other regulators also, I've seen it on fuel gas reg's lots of times. This issue is all about oxygen. A few drops of oil inside the regulator on the high pressure side, will turn your tank into a bomb. A full high pressure tank will cause more damage than you can imagine. 
Always turn off tanks after use.
Always have tanks chained in upright position. 
Always install caps on unused tanks
Never transport a tank horizontally (like on lift truck forks) I saw the result of one that had the valve knocked off and ended up outside after rocketing through a block wall.
Inspect hoses regularly. 

These are things that come to mind in my early morning fuzzy head before finishing my coffee. lol It's been many years and I didn't look any of this stuff up so, . . take if for what it's worth.


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## mizlplix (May 1, 2011)

The 7/acet, 40/oxy setting is a general one and is needed when cutting. I try to use nearly even settings when just welding, like yours. The 40 PSI is needed to stop oxygen starvation when you hit the cutting lever. At a lower oxygen setting, it is good for welding only. 

When using a large "Rose bud" heating tip, I really jack up the acet setting to max. 14/acet and 20/oxy. I try to keep the two gas pressures nearly even to prevent oxygen from backing up in the acetylene hose causing a flash-back.

Yes, extremely high acetylene settings are not recommended as it self-ignites under certain conditions like Diesel fuel will.

That is prevented inside the acetylene tank by filling it with a foam like material and flooding it with liquid acetone to dissolve the compressed acetylene into.

There is only a small bubble of high pressure acetylene in the bottle, at the extreme top. That is why it is very important to have the torch bottle set standing upright when operating as the acetylene has to emerge from the acetone slowly as it is consumed. 

Thanks for mentioning this point. 

miz

(See disclaimer in article 1)


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## JRP3 (Mar 7, 2008)

Anyone have experience with Oxy/Propane cutting torches? I have a setup but haven't used it much, I think one of the regulators may be bad and varying pressure. I have the proper tip which is different than Acetylene.


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## mizlplix (May 1, 2011)

The end of the MAP or Propane tip has a recess in it to generate a slight amount of heat to help keep the flame lit.

It will require extra pre-heating when cutting and travelling slower than with acetylene. 

A lot of junk yards use propane because it is a lot cheaper than acetylene.

In cold weather the propane bottle will ice up sometimes too(the transition from liquid to a gas requires some heat input)

If your secondary pressure varies when standing or during use, it needs looked at.

miz


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## mizlplix (May 1, 2011)

OK, to touch lightly on T.I.G. welding. (Also called Heli-arc)

TIG welding is very similar to gas welding, but uses an electric heat source and added filler material with an inert gas shield to occlude oxygen, moisture and other contaminants. 

Matching filler material can be used as can high temperature silicon/bronze or even some alloy of the parent metal.







A rapid, pin point heat source and an easily controlled weld profile are it's chief advantages.

It utilizes an air or water cooled torch to hold the non-consumable, Tungsten electrode which allows the welding of almost anything that will conduct electricity. (It only supply's the welding heat)

The electrode diameter is chosen by the welding current required. Small current/thin metal/small diameter electrode, ETC. 

It requires a special collet and collet body to hold each diameter of tungsten rod, which will get expensive to keep all of that inventory.(Collet-body-rod, for each diameter.....) 







Outer collet body








Inner collet-the gripping part.


For my shop's needs, _I only use two sizes, 1/16" and 1/8" diameters._ AND _I use the 1/8" collet body for both_. I only change to the collet that fits the rod size. They all are based on a wedge fit and will tighten down nicely. (Every little bit helps...) 

When the electrodes are new, they are blunt (flat) on each end. When welding with DC current, they require a sharp profile and must be sharpened. The direction of the sharpening grinder marks will affect the welding arc. The electrodes MUST be sharpened in the direction of the electrode body, NOT cross-ways. The electricity will exit the rod along the scratch marks....and they need to go out straight to form an even, usable arc. When welding with AC current, a "ball" shape on the end is advantageous. It is formed by cleaning the end of the rod and momentarily "zapping" a piece of carbon with the machine set on DC reverse polarity. It instantly over heats the tungsten and forms a molten drip on the end. This is necessary for stable AC welding current.

The material of the filler rod needs to be compatible with the parent metal. In some cases an alloy rod needs to be used to weld two dissimilar metals together. The diameter of the rod is determined by the deposition rate required not necessarily the material thickness. What ever you use, it needs to be extremely *CLEAN*. I keep stainless steel wool to clean each rod just prior to use. 

Which brings us to the weldment it'self. The workpiece needs to be extremely clean as well. NO rust, paint or oil of any sort. Everything is contamination in a TIG weld. It needs to be both scrubbed and chemically clean in the weld areas. 

Which brings us to the gas shield. Argon provides a clean, inert envelope for the welding/blending process to take place. It comes from a bottle and uses a flow regulator to set the gas rate. There are many variables when determining the optimum gas flow rate, But I usually set it at 23 Cu/Ft/Min. as a good starting place. Obviously, TIG welding is best done indoors under controlled conditions. 

As with most forms of welding, joint prep is important. As mentioned previously, clean, clean and finally, clean. 










In short: AC=balanced arc, cleaning effect, used on aluminum mostly.
DC/straight polarity(electrode -)=good penetration, narrow welds, cooler electrode-stays sharp and clean. Used on most metals(not aluminum)
DC/reverse polarity(electrode +)=shallow penetration, wider welds,over heated electrode(melts point to a ball) and picks up contamination from weld metals from the current coming up from the work piece.

(NEXT:Initiating the weld sequence)


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## MalcolmB (Jun 10, 2008)

I've found this to be a really useful site for general welding tips. The videos on welding techniques (TIG, MIG and stick) are especially handy: http://www.weldingtipsandtricks.com/tig-welding-videos.html


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## mizlplix (May 1, 2011)

When instructing, the students received knowledge from both classroom teaching, shop work and reading supplemental materials. I am attempting to give the classroom part without the benefit of the shop work.

*Reading other sources and you tube videos are encouraged,* as they include things I do not. 

My diatribe is merely those points I used during my 8 year teaching career those 25 years ago. I am certain technology has advanced in the meantime, but many of my points are still valid.

At that time the equipment was all analog whereas today it is "spacecraft" by comparison....LOL

But, we still covered stick electrodes, cored wire, micro-wire, submerged arc, spot (resistance) welding, Cad (thermite) welding, TIG welding, electron beam and laser on most common materials.

We ended up the year with certifications in the two processes of your choice, a total of four if you stayed the entire 4 semesters. Your certificates were all position, material specific and unlimited thickness. The plates were the 1"-double bevel- 1/4" root gap=two coupon-side bend-acid etched type.

Certifications look something like this:









Contrary to popular belief, welding certificates (certifications) are good for life, but employers can ask for a retest on employment (for their files).

Miz


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## mizlplix (May 1, 2011)

*Cutting and heating*

From here on out I will only be adding to the content as I have time. I have taken on a rather large home improvement project.

This section is cutting and heating tips.

Oxygen/acetylene cutting of metals is easily done and extremely useful.

Acetylene is the most efficient gas for welding.

Acetylene is an explosive gas. For this gas to be stabilized in cylinders, the cylinders must have a porous mass packing material with small cellular spaces in which acetylene gas can collect. The porous mass is saturated with acetone, in which the gaseous acetylene dissolves. Maximum acetylene cylinder pressure is limited to 250 pounds per square inch gauge (PSIG) at 70 degrees F.

Acetylene withdrawal pressure is 15 PSIG. To minimize the withdrawal of acetone, acetylene should not be withdrawn at a rate of more than 1/10 the capacity of that cylinder per hour of intermittent use or 1/15 for continuous use.

Brazing and soldering can be accomplished with welding tips that use any common fuel gas because they do not require the higher heat that fusion requires. Welding tips to be used with alternative fuels often require a recess at the tip outlet to prevent the flame from blowing off the tip end.
A heating tip is attached to a torch handle with mixers that mix the fuel and oxygen and supply it to the tip. One common mistake welders make when using heating tips is to starve the tip by not supplying it with enough fuel. Lack of fuel causes the flame to regress into the tip, resulting in backfires and flashbacks. Welders need to be aware of the fuel supply requirement for the heating tip they are using and maintain that supply of gas by manifolding cylinders together if necessary.

There is a limit to how much gas can be withdrawn from a single cylinder. Many welders try to run large heating tips off a single cylinder of acetylene. The maximum withdrawal rate for a large, 300-cubic-foot acetylene cylinder is only 30 cubic feet per hour. This is enough acetylene to run only a very small heating tip.

If a heating tip starts to backfire, the welder needs to shut the tip down and check the fuel gas supply. Continuing to work with a backfiring tip can be hazardous to the equipment and dangerous to personnel.
Check valves and flashback arrestors can help prevent reverse flow, backfires, and flashbacks. These devices are designed to enhance operating procedures and help protect personnel and equipment when dangerous conditions exist.

Welders must be sure to check the capacity of the check valves and flashback arrestors used to ensure they have the flow capacity needed. A check valve or flashback arrestor without sufficient flow capacity can restrict flow and create serious problems.

Most torches are called "combination" torches. That is because they are made to do several different jobs. They consist of a mixing chamber (handle) and some attachment.

One attachment is called a *"Rosebud"*. It is a heating tip. It mounts directly on the mixing chamber. It uses the two valves mounted to the handle to set the flow. There are many sizes. The larger sizes require that several bottles of both oxygen and acetylene be paralleled to provide adequate gas flow. When it is used, the regulators must be set at maximum and as evenly as possible or problems will result. The oxygen regulator needs set at 20 PSI and the acetylene regulator needs set at the maximum of 15 PSI. The standard lighting routine needs followed for proper use and to prevent blow outs of the flame.

One attachment is called a *cutting head*. It has one oxygen valve, one cutting lever and a removable tip. Cutting tips come in many, many different sizes. From a 0-0-000 to a 2-1-20 or larger.

Another attachment is a *welding tip*. They come in various sizes too. It mounts directly on the mixing chamber. It uses the two valves mounted to the handle to set the flow. 

Metal Thickness & Tip size
_______________________
1/8"------------------000 
1/4"------------------00	
3/8"------------------0	
1/2"------------------0	
3/4"------------------1	
1"--------------------2	
2"--------------------3	
3"--------------------4	
4"--------------------5	
6"--------------------6
10"-------------------7
12"-------------------8

*TRICK:* If all you have is a #00 tip and you need to cut a 3/4" plate, it is possible to do with care. First of all, pre-heat the piece, top and bottom until it is just under glowing a dull red. Then start your cut. Use a "C" shaped tip movement back and forth like you would do if you were stick welding a large weave pass. Go slowly! The idea here is to remove the metal and allow it time to run out the bottom of the cut. You need to maintain the inner edge of the cut along your cut line and it will look like it was cut with the proper sized tip.



When cutting a hole in metal, you can get molten metal all over you if you are not very careful (OOPS, you already found that out....LOL)

*TRICK:* Cutting a hole without getting burned.....Yes, it is possible and easily done.

1-Preheat the piece. If over 3/8" in thickness, preheat the bottom too.

2-Pick a starting spot along a side away from you (not the back or front)

3-Heat that spot to get a starting puddle.

4-You need to do two things a once now....Hit the cutting lever gently and drag the tip TOWARDS yourself. (It gives the molten metal a channel to blow out-away from you) It will quickly cut through the plate and the metal will then go out the bottom. 

Try it, you will be amazed at how nice it works.

*TRICK:* As stated elsewhere- The *standard lighting routine* for an acetylene torch is essential to achieve and keep as close to a neutral flame as possible. 

First, slowly turn the regulators on, taking care not to "pop" the diaphragms when doing so. 

Set the acetylene pressure to the setting for your attachment/tip size/material thickness. Close the valve.

Set the oxygen pressure for the attachment-tip size/material thickness. Close the valve.

If a Rosebud or other directly attached unit is being used, the two valves on the handle set the flame. If a cutting attachment is used, the oxygen valve on the handle is set wide open and the oxygen valve on the cutting attachment and acetylene valve on the handle is used to set the flame. (failure to do so will not give full pressure to the tip when the cutting lever is depressed)

Slightly open the acetylene valve(1/8th turn or so). Use a spark type ignitor to light the gas.(*NEVER* use a butane lighter). Open the acetylene valve until the flame begins to pull away from the tip (watch closely!). Then turn it back a little.

Slowly open the oxygen valve. Watch the center of the flame as it forms a "feather" like appearance. Keep opening the valve as the feather gets shorter. Stop when the feather ends and the blue part of the flame gets lighter.

A lighter blue in the flame is a oxidizing flame. A darker blue (without any feather) is called a carborizing flame. You want half way between the two. That is the proper flow and flame formation for that tip whether it is a cutting, welding or Rosebud. 

*TRICK:* If the tip being used is too small for the metal thickness, you can turn it up one more time by turning the acetylene (until the flame is pulling away) then reset the oxygen (getting the neutral flame back). A cutting tip will need further adjustment by pressing the cutting lever and adjusting the acetylene knob while the cutting lever is pressed to get a neutral flame back.

*TRICK:* After cutting a weld or other metal piece as close as possible, further smoothing can be done with the torch and save many hours with the hand grinder. 

It is called *"WASHING"*. It is simple to do. A standard cutting tip can be used, but a scarfing tip makes it easier. Pick a starting spot at one end of the metal to be removed. Hold the flame close to the metal. Turn the torch sideways and actually lay the side of the cutting tip on the metal next to the area to be removed. After a small spot has begun glowing a bright red and a molten puddle has formed, slowly open the oxygen valve until the flame is blowing the metal away (DO NOT use the cutting lever). Move slowly and move the tip in a "ZEE" pattern across the area, following the line to be removed. PICK THE CORRECT SPEED .....Too slow and it will gouge out too much leaving a nasty rut. Too fast and none will be removed (you must stop. close down the extra oxygen to let it heat up and start again). 

Practice this! It is VERY useful! 

*HEATING:* Not much to be said that common sense will not cover, But......

Avoid local overheating as it ruins the work piece by oxidizing it, causing a local hard spot, an ugly scar and a crack starter. When cutting you want to keep the blue part of the tip close to the piece, but in heating, you keep the blue portion of the flame away from the metal, gently moving the flame around as not to form a melted puddle....

When heating to bend a piece, heat a large enough area and just apply enough heat to make the metal bend. Do NOT just heat it up cherry red and bend it over! (That is a rookie mistake). If you want a professional looking job, use heat gently. You can vary the heat to even out a large, gradual bend to keep it even, by heating in the right places while slowly applying the bending force. Do it slowly-evenly. There is no rule telling you to go fast when bending metal. 
(for me). Thx to all who added some points.

Miz


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## order99 (Sep 8, 2008)

So_-_now that we're on the brazing/welding with gas portion of the tutorial, I have one question-how do you tell, visually, when a join is 'wicking' properly? should I be able to actually see the brazing material being drawn into a properly fishmouthed or other close, properly heated join? Or do I just fill it in, add a little on the surface for extra bracing and polish smooth? Due to lack of space and extreme poverty I'm limited to MAP gas and brazing rods only...

Best of luck on the home improvement project BTW!


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## mizlplix (May 1, 2011)

Good question:

When brazing, it is very important to wear eye protection. There is another reason also...to be able to see the brazing process.

Brazing causes a very bright yellow light that the eye can not see through unaided. It needs a dark lens. Try it with clear glass and then with sunglasses on. Big difference.

Then it is easy to see when the weld puddle gets "wet" and starts to flow. 

You first heat a spot, add a drip of filler, continue heating until it wets and flows out. Add another drip/flow/drip/flow ETC. It gets to be a regular rhythm thing.

It is customary to first do a thin layer to assure it fills properly, then the second (or third) pass over does the proper build profile.

Miz


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## Duncan (Dec 8, 2008)

mizlplix said:


> Good question:
> 
> When brazing, it is very important to wear eye protection. There is another reason also...to be able to see the brazing process.
> 
> ...


Hi Miz
Are you talking about "bronze welding" here?
I think Order was asking about brazing
The two processes are different - 
As I understand it brazing (to be pedantic) uses close fitting joints and the "filler metal" wicks into the joint
Whereas bronze welding (often called brazing) uses the filler metal to produce a fillet

If Order is using the same rods that I do for "brazing" he may be using a rod designed to form a fillet rather than one designed to wick


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## mizlplix (May 1, 2011)

I did not distinguish between the two processes because they both are similar in application.

His question:


> I have one question-how do you tell, visually, when a join is 'wicking' properly? should I be able to actually see the brazing material being drawn into a properly fishmouthed or other close, properly heated join? Or do I just fill it in, add a little on the surface for extra bracing and polish smooth?


I feel my answer covered his questions.

Question 1=


> how do you tell, visually, when a join is 'wicking' properly?


My answer=


> You first heat a spot, add a drip of filler, continue heating until it wets and flows out.


Question 2=


> Or do I just fill it in, add a little on the surface for extra bracing and polish smooth?


My answer=


> It is customary to first do a thin layer to assure it fills properly, then the second (or third) pass over does the proper build profile.


I feel my comments apply to both processes. Where I was raised/taught/worked, the two were called brazing as it used "bronze" or an alloy. Later they came up with the "Silver brazing" name for a more fluid process, using other alloying metals, to which you are referring. 


To be pendatic....

*Bronze welding:* The steel tube and steel plate have been heated to a dull red heat. The ‘bronze’ filler rod (coated with flux) is then introduced to the joint. It flows onto the two surfaces, forming a ‘fillet’ around the joint, joining the two surfaces.

*Brazing:* Flux is applied to the joint, to prevent oxidation of the surfaces. The steel tube and plate are heated to bright red heat and the brazing rod (filler rod) applied to the joint. The end of the filler rod melts and "wicks" around the joint, through capillary attraction.

When ever I would "Braze" or "Bronze weld", I always applied a second go-around to make sure it got pulled into the joint, because I am somewhat of a pessimist. 

*Under field conditions*, I would often repair a "Brazing" job with a "brass welding" job when it required me to apply it under neath something I could not easily "Braze" again, like a Formula Ford frame after a crash. "Brass welding" being easier for me in awkward situations.


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## Duncan (Dec 8, 2008)

Hi Miz

So there is no real difference in the properties of the fillers used?
I had thought the "brazing" filler had a significantly lower viscosity when melted,
I have done a fair amount of "bronze welding" but no proper "brazing" so I have no experience of the difference


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## mizlplix (May 1, 2011)

You might have missed this:


> Later they came up with the "Silver brazing" name for* a more fluid process,* using other alloying metals, to which you are referring.



And under "Brazing":


> The end of the filler rod melts and "wicks" around the joint,* through capillary attraction*.


(in "brass welding" that phrase is missing)

The Furnace Brazing process is where the item is fit up tightly, usually with socketed joints and the joints are coated with a paste of flux and powdered metal. It is set into a fixture before being placed in an oven and heated up to the point where the powdered metal flows through all of the joints evenly. It is then allowed to cool before removing it from the fixture. It is a widely used process that lends itself to production line assembly.

I would like to ad: Brazing needs a tighter/better/more accurate fit up job than brass welding generally. Also the joint design is different because the brazing process needs as much surface area contact as it can get because of a much smaller external build up (filleting).


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## piotrsko (Dec 9, 2007)

unless I missed it: The two processes are somewhat mutually exclusive. One cannot weld a brazed joint (because of materials contamination), but if you can accept the lower joint strengths, you can bronze braze a welded joint.


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## mizlplix (May 1, 2011)

The higher bronze welding temperature melts out the old brazing filler, which drips on you if you are not adept....

The pre-heat temperature is raised over that of the lower temperature brazing process, which pretty much eliminates any trace of it, plus you are adding more filler in the external face of the old brazed joint, where it sticks easily.

As stated: I have used it to do a field repair of cracks in a Formula Ford frame (that was brazed), because it was easier for me to do in the field.

The brass welding process uses flux on the rod and does not depend on the flux being in the joint, as brazing does.

You are correct: you can braze a bronze welded joint.(Without removing the old brass filler)

Your observation about contamination is valid when you try to arc weld a previous repair on a brazed or bronze welded piece(or something similar). That really sucks.


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## mizlplix (May 1, 2011)

I really appreciate everyone's responses because I have had to go back and make corrections because of clumsy wording or an out right mistake on my part. I do not wish to leave erroneous information. This stuff is hard enough to learn.

Miz


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## DIYguy (Sep 18, 2008)

The whole Braze, Bronze, Welding, Soldering area of discussion is really tough. It's tough because of the non-standard terms (rampant in the welding world), the history (kind of the beginning of metal working, this stuff) and modern general understanding. I don't think it matters all that much what you call it (although I long for clear distinction) as long as u understand what you can do with the different alloys and what you can expect from their service life.

Generally speaking, Bronze is a Copper/Tin alloy. That said, it can have many other alloying combinations which significantly affect it's properties.
Brass is generally regarded as a Copper/Zinc alloy . . with somewhat similar alloying possibilities. FWIW, many of the brass alloys have slightly higher melting temps than the bronze ones. . . interestingly enough. . . although some bronze alloys offer tensile strengths far superior to brass.

One area where we get controversy is when we add the word "welding". Most people just think of this as metal joining, and of course it is. The problem is that strictly speaking, "welding" is truly only when you melt base metal and form coalescence. In this light, no process using Brass or Bronze alloys on steel components, is truly welding. Now if, for example, you repair a cast bronze component with a suitable alloy filler, this would be considered "welding". 
Some folks use the distinction between "brazing and welding" to differentiate the "Brass vs Bronze" filler metal. It's a logical deduction in many ways because the joint formed with many of the bronze alloys does not resemble many of the brass filler metal joints. As referred to by some already, the reinforcement type appearance of a bronze joint vs the tight fitting, wicking action often seen in brass alloy joints.

I think the important take away is that some of the bronze alloys, specifically the Aluminum-Bronze and Manganese-Bronze fillers can give some very high strength joints and there are some specific alloys that will handle joints with gaps much better. Of course bronze can offer a joint with reinforcement also, and no undercut (at the toe) which also contributes to better service life/higher strength. (of course brass joints don't cause undercut either, I was comparing to steel welds)

This is a bit of a brain dump from some cobweb memories so, I hopefully made some sense.


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## order99 (Sep 8, 2008)

Many thanks to all of you for the clarifications. It seems that i'm at least on the right track with my techniques (even if those techniques involve bracing my arm on an armrest and patiently waiting for the rod to flow due to the lower temp of single tank of MAP gas!).

I'll see if I can get some of that lower-temp 'silver-bronze' rod that the classic bicycle manufacturers used to use for their hand-lugged frames...if that doesn't work i've got some coat hangers from the late 60's and early 70's (real brass with rolled paper 'flux' built in!) Dad swore he used to be able to use these with just propane, so why not? 

Thanks again for the brain candy..


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## mizlplix (May 1, 2011)

DIY:

Yes, you hit the nail right square on the head. It is difficult to be really precise about a subject if the technical language and specific words do not exist or have two meanings. Often in just one generation, the meanings of words will change, making communication difficult. 


I see this all through these forums. And usually it causes a chain reaction of questions and attempted corrections, along with it, the original question and subject can get lost.

Miz


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## DIYguy (Sep 18, 2008)

mizlplix said:


> DIY:
> 
> Yes, you hit the nail right square on the head. It is difficult to be really precise about a subject if the technical language and specific words do not exist or have two meanings. Often in just one generation, the meanings of words will change, making communication difficult.
> 
> ...


Thanks Miz. It's so true. That's why I wanted to focus a bit on the important part, not the nomenclature. 
The most credible governing body for welding terms and definitions (this is a publication) in north america, is AWS or the American Welding Society. I have a version somewhere in my basement. Some of the most commonly used terms are not standard, here are some examples.
MIG- meaning Metal Inert Gas. This is technically a misnomer as well as a non-standard term. Proper term, GMAW (used more extensively in Europe, MAG.) The problem here is that, as you know, the shielding medium is not usually 100% inert. Hence MAG for Metal Active Gas.
TIG - meaning Tungsten Inert Gas. Non standard term. Correct term, GTAW.
Stick- of course. SMAW
These are the three most common processes. I don't worry about it too much, except when teaching someone. . . otherwise, most people know what the other means. Some of these processes have multiple other terms as well that are based on welding equipment/filler metal company terms in some cases, like Heli-Arc. Or better yet, a variation on metal transfer mode, like "Short-Arc".
I was a member of AWS for many years and as a sub-committee member, helped to create a couple of their publications. It's rather tedious, as u can imagine.
You've done a great job here Miz and surely helped lots of people. Keep the focus on the important part.


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## DIYguy (Sep 18, 2008)

order99 said:


> Many thanks to all of you for the clarifications. It seems that i'm at least on the right track with my techniques (even if those techniques involve bracing my arm on an armrest and patiently waiting for the rod to flow due to the lower temp of single tank of MAP gas!).
> .


If you can afford to mix oxygen with your MAP you will raise the temp significantly and have no issues. If not, look for a torch that draws some ambient air into the stream, this helps a bit also. 
If the job is not too big, u can pick up a small oxy-fuel package (like Bernzo-Matic?) from a store like Princess Auto for like $50 on sale I think. Granted the bottles are small, but it is rather effective for a short time.


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## jwr813472 (Jun 1, 2010)

This is interesting reading. I hope you have some MIG welding primers tips in the future. I"m sure I have plenty of bad habits to unlearn.

OOPS!

Somehow I missed a few pages. Good stuff!


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## FrankLee11 (Jul 24, 2017)

This is attractive Welding 101 incredible work lower than around 1-4 and at low speeds it is some of the period spirits moderate or quick. Is that typical for these welders? I trust I've set it up effectively, in that it's as well-lit as it can be deprived of slipping or unspooling.


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## dcb (Dec 5, 2009)

Hey Frank! You get tired of all the noobs putting vortex generators on their humvees and expecting (or claiming) a 20mpg increase too?


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