# forklift motor adapted for a heavy boat



## kennybobby (Aug 10, 2012)

What sort of cells and battery pack are you planning to use? 

Pictures are always good, we never get enough of them, and it helps to see how other folks solve the problems...


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## john61ct (Feb 25, 2017)

Yes, pity didn't document the research / decisions made along the way.

As many details as possible would be most welcome.


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## Mark in Portugal (Jun 13, 2019)

I haven't decided on the battery yet; I live in Portugal and the boat is 1,500 miles away in Amsterdam. When I'm there I have no transport and little time, so I won't be going around scrapyards. 
At the moment I'm leaning towards a used forklift block, but more research is needed. I'll also need a charger / battery tender.
I rarely move the boat, I use it for work when I'm there and the rest of the time it's a balcony for my rental houseboat. 
In a few years, all transport in the city has to be emissions free; and for this boat to be moored in town, it must be navigable. 
I'm worried about self discharge of a big lead acid battery; I can connect to mains, but I've read that loss can be several percent per day. Over a year, that works out to a lot of electricity. 
My calculation is that to transit through town, I'll need 5kwh used in a 1 hour period. I only need to go one way, then I can recharge overnight. 

I saw this motor + control for sale from a kid's go cart project, so I went for it. 
It's an intermittent use motor; I guess I should have walked away, but instead I decided to upgrade the cooling and go for it.

I increased the cooling air a lot and added a water jacket.








I had the boat drive shaft mailed to me from Amsterdam.








My first idea was to make a new case from stainless; but I couldn't source tube that big. I thought about making a roller [wanted one for a while] and bending it out of plate but the boat has a heat exchanger and glycol circuit in it so went for simple cheap mild steel.








I got a big pipe from a scrapyard, and flame cut these rings from 8mm plate for the ends.








The field coils will be removed for welding, so I need access holes for the field coil screws.









The holes will have 3/8" pipe plugs, because I have a 3/8" pipe tap.








More later


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## Mark in Portugal (Jun 13, 2019)

The water in + outlet tubes will be set at an angle; I used stainless pipe for these parts. 









Parts 









I ground a grove on the insides of the end rings, to minimize the internal gap which will be vulnerable to corrosion.








After welding;








heat conductive grease on the armature, copper grease on the screw thread, and permatex aviation form a gasket on the screw flange. I'm trying to get as much heat into the water jacket as I can. 








Pressure testing the water jacket;








The front cover was made for a hydraulic pump to fit on.








Now it has better air flow.








I wanted to integrate the control box cooling into the motor case, but the geometry just wouldn't work, so I made a separate cooling box that will screw onto the 3/4" inlet pipe. 








More later


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## Duncan (Dec 8, 2008)

Looking excellent 
In fact looking like severe overkill!

For batteries I suggest a Chevy Volt pack - I'm very happy with mine


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## Mark in Portugal (Jun 13, 2019)

Duncan said:


> For batteries I suggest a Chevy Volt pack - I'm very happy with mine


It depends on what I can find, and at what price. Like I said, I have little time when I'm there, and no transport. 

The boat doesn't care much about weight; a ton is ok. The life expectancy, charger cost, and self discharge rate of the battery are issues.


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## Mark in Portugal (Jun 13, 2019)

It took me a while to work out the gear reduction, because I don't know the size of my propeller; I put it on the boat 20 years ago, and lst saw it out of the water 4 years ago. 
I got a neighbor to go onboard, lie down on the stern, and measure it in the water. 
It turns out I need 5.3/1 reduction, give or take.
That means I need to disengage the electric when it's not in use. Also, a single pulley set would mean a large driven pulley which might not fit in the space between the shaft flange and hull.
So I did this; a 3.8/1 gear set from a junk car, and a new pulley and belt set I bought from a UK supplier [1/2 what it would cost me to buy in Portugal]
I've welded a ring to the flange that was mailed to me from Amsterdam, and bolted the large gear to it.








Here I've pressed + welded the small gear to a mild steel rod, cutting to fit bearings.








Cutting a slot in a piece of flat stock for the belt tension adjustment.








lining up before welding the mounts;
















The motor shaft is short, with a splined end.








I got the female with the motor, and I added the press collar.








Pressing onto the motor;








The rear end needed a big cage fan, which I had on a 1/2hp blower of similar rpm. So I need a shaft extension / adapter.


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## Mark in Portugal (Jun 13, 2019)

Pressing the shaft extension / fan holder








I bolted the fan to the extension
















To make the motor reversible, I had to split the field windings from the armature brushes, and add 2 more connection bolts. The connection plate already had the 2 spare holes for them, so I guess the motor has a reversing version.








I want / need to monitor the water temperature, and the outgoing air temperature. I bought 5 electronic thermometers for 10 euros. I had to extend the wires; this causes a 0.2 degree error I found, no problem.
Here I made a fitting for the temp probe to fit into the water jacket;








Soldered it in; 








I don't want the air temp probe attached to the metal, so I made this plastic holder from polycarbinate.








The instrument box will only be brought out on deck when the boat is is use, because there is no cabin and no helm. It's an open boat with a tiller. 
I made a rheostat box with a lever for the speed control, that will be attached to the existing Morse control lever, and a pair of limit switches to attach to the marine gearbox to switch the forward/reverse relay. I forgot to take pictures of the speed control box, it's a whole thing of its own though. 
Here the instrument box is connected to 12v for testing. The thermometers get power from the drive battery through a little V-reg circuit I made from leftover bits.








I ordered 2 24v circulation pumps from Ebay, 1 for raw water and 1 for glycol. In series, they can run from the 48v system. I was surprised at how small they are, but they work as advertised. It doesn't need a whole lot of flow anyway. 
What do you guys use?


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## Mark in Portugal (Jun 13, 2019)

The last of the pictures;

Here is the lower pivot tube made from 1" plumbing pipe. I bored it internally to 27.2mm to make it roundish.
Set into it is a 27mm rod. 
In the foreground is the alignment jig.

The idea is to bolt the jig to the prop shaft flange, set the rod in the holder, and weld one end in place; the other end is bolted to the plates in the picture one of which is also welded to something or other [I'll decide when I get there]. The top plate unbolts and the motor unit slides on. I made collars with set screws to set the position on the shaft as required.








It will pivot up to disengage the gear when not in use.

I realized the bolts and slots thing is nowhere near strong enough to hold the belt in tension, so I made this adjuster from a couple of old head bolts and some hard hex rod I have.






















That's more like it.


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## Mark in Portugal (Jun 13, 2019)

I forgot to post a few pictures of the old boat.
This thing is 14 meters [46'] long, 12-14 tons, and 100 years old.
I've owned it for 35 years.
It's my smallest boat.
Maybe the newest too [dates are guesswork].

It was once a sailing barge used for small loads in shallow water, like between farms and that sort of thing. 
I made the deck around 15 or 20 years ago, it had a full length house on it before that.


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## kennybobby (Aug 10, 2012)

This is an awesome build. i just love all the machine work and welding, the slot cutting "mill" is such a clever solution. Thanks so much for sharing your pictures.


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## Mark in Portugal (Jun 13, 2019)

Thanks, Ken;
I have to say I'm quite humbled by some of the projects I see o this site.

Where I live [Portugal] modified vehicles aren't allowed on the public roads [Theoretically, it could be done but in practice it would be harder than the build itself].

But maybe I'll build an electric tractor one day; that would be utterly impractical [total yearly energy use not enough to make it worthwhile], but good fun.


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## MattsAwesomeStuff (Aug 10, 2017)

Amazing project and thanks for all the photos.

It's neat to see things that are completely different than the norm around here.


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## remy_martian (Feb 4, 2019)

Interesting...

What make/model junk car is that 3.8:1 gearset from and what's the approximate diameter of the big gear?


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## Mark in Portugal (Jun 13, 2019)

A friend of mine scrapped his little ford escort and asked me if I wanted the motor; this was about 15 years ago. 
I thought I'd use it for a generator...
Anyway, I had it sitting around with the gearbox still on, which is why I chose it.

it was a 1985 Ford 1.1 liter diesel, 5 speed I think. 
I've used some of the other gears for other projects; they're incredibly hard. 

The large gear is around 8". 

This is the final reduction, it's actually the ring gear that was on the differential. A front wheel drive, it was integrated into the gearbox.
the other gears are smaller, and range from 1/1 to 3/1. the teeth are different on each gear, so they can only be used as pairs.

I assume other small cars are built in a similar way.


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## remy_martian (Feb 4, 2019)

Thanks for the quick reply! Even the Tesla gearbox does the final reduction as you've described, so not just "small" cars.


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## brian_ (Feb 7, 2017)

Mark in Portugal said:


> A friend of mine scrapped his little ford escort and asked me if I wanted the motor; this was about 15 years ago.
> I thought I'd use it for a generator...
> Anyway, I had it sitting around with the gearbox still on, which is why I chose it.
> 
> ...


The final reduction gear set with parallel gears (rather than bevel or hypoid gears) and the output gear as a ring (bolted to the differential carrier) is normal for any transverse transaxle; these are used in most front-wheel-drive vehicles (of any size), some mid-engine cars, and typical current EVs.

The other gear sets are typical of any manual transmission, of any size, in either orientation (transverse or longitudinal).

Most EVs have a first stage reduction like the small gears, and a final stage with the driven gear in a ring around the differential; they are a single-speed version of a typical transverse manual transmission.


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