# Ground up carbon fiber ev build.



## Equisail (Mar 1, 2013)

Hey there everyone. I've been checking these forums for a good long while now while researching my ev build. I captain an electric diesel skipjack in southern Maryland, and I have extensive working knowledge of the systems involved in converting a vehicle to electric propulsion through my work with the skipjack. For info on the boat search Caleb w. jones. 

Anyway I've decided to build my own 2-4 seater carbon fiber chassis and body ev. My project goals ate to keep total vehicle cost under 10,000. Early research seems to favor the possibility of going cheaper. 

More to come on design and components


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## Duncan (Dec 8, 2008)

Why carbon fiber?

Unless you are using pre-pregs S glass has a better strength to weight ratio
And its a lot cheaper and easier to use

Theoretically carbon fiber is stronger BUT it is so difficult to wet out that you end up using too much resin and ending up with a material that is heavier than an S glass and epoxy mix

I wanted to make a composite tub but for my first car here (NZ) I chickened out and went steel

The next one will use honeycomb sandwich boards "folded" into the main structure


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## Equisail (Mar 1, 2013)

Well I'm using the carbon fiber to get the lightest possible chassis. I'm thinking on using 1"x1"x60" or 78" square tubing. I've researched some materials that prove pretty promising for strength to weight. Two of my siblings are mechanical engineers, they are going to review my designs and optimize them for strength and simplicity. I'm planning on building the vehicle in stages. Haven't found an oven yet but I have a few friends who are coming up with leads as I sit. 

My goal for the vehicle is to build the absolute lightest rolling chassis possible. I'm looking to build a base platform similar to the skateboard concept. Body shells can be custom fabricated. 
So far the vehicle is a designed to have a tube framing chassis. In rear I will be using an aluminum plated bac carbon axle used in four wheeler and go kart applications. Weighs just 1.65 lbs and stress tested to nearly 2000lbs. Cart will be a two seater with enough room behind seats to potentially add 2 more seats later when battery motor and controller budgets allow for improvement.
Rear wheels will be set narrower to front wheels much like a reverse trike similar to T. rex. If my rough calc are right the finished chassis structure, without motor batteries and wheels etc.. Should weigh at absolute most 25-35 lbs. with the materials I'm using. My siblings are going to check and improve basic design for materials/strength/weight.

I've located a 6 speed motorcycle transmission chain driven. That way I can play with sprocket sizes to optimize performance. 
Looking at running a 120v advance motor and Curtis 500 amp controller.
The set up is capable of running at 36v 74v and 120.
I'm going to buy battery pack in stages. Still researching best battery candidates. Any one have good start? Prob want to go lithium. Unless MIT can make me some carbon nanotube paper batteries! I wish! Wonder if well ever see em


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## Equisail (Mar 1, 2013)

Meant to say motor weighs in at lil under 90 lbs. and transmission is right at 40lbs. Total vehicle weight without battery pack, springs or tires should weigh in at 165-175lbs max.


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## Equisail (Mar 1, 2013)

Preliminary budget

Motor and controller total 1216.00
Transmission 200.00 used 550.00 new
Carbon fiber tubing total 460.00
Joint plates and prepreg adhesives- still researching but budgeting 250- $500 which should do it. 
Wheels- own (motorcycle) looking at other possibilities as well. Potentiometer included in motor controller pricing. 
Brakes-disc owned 
Chain and sprockets owned 
Total est. cost rolling chassis without batter pack 2126 give or take a few hundred.


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