Good morning,

I have to build a +- 2.5 liter CF air tank that hold 10 bars continuously.
My plan is to shape a cylinder (7.5 cm diameter and 15cm long) in a block of foam that need to resist epoxy resin under vacuum, wrap it with 6 layers of CF, after cooking I will drill two holes where I will later install some plugs, filling through them acetone to dissolve the foam and get a final clean inside piece.

My questions are :

- is my plan the easiest or do you have a better idea ?
- which foam to use (I want to avoid glue in the process and 10cm height is your only option) ?
- how many layers of 400gr CF would you recommend (my intention is 6) ?

Thanks for your kind advice.

               

So the part is now finished. I will test it on the road as soon as the weather allow me, and if approved, I will bring it to the track to address the reliability. Some feedback now...

- I decided as a test to glue 3 inserts on one side but not on the other where I just added Teflon tape. No issues on both side.
- The core cylinder is far too strong
- You need to be 2 or 3 people to tow correctly as it was a nightmare alone. Very hard to keep the tension, wet it, and deal with everything going not that well...
- The weack point is the design of the side. I will probably build another one using the rocket technics as my tank could be then 20% lighter
- Need to be tested at the track to address the stress issues, vibrations and heat.
- Final weight saving is 682gr where the optimum should be around 800gr.

Does anyone else feel this chap has just built a bomb for his car! ?

Chris, as said, this is too strong so it won't. I actually fear to get some leaks as this will be shaked like hell in a 100+ °c environment at the sides of the tank.
I am now starting a second version with inside hermetic plastic tank that I expect to be stronger, lighter and more reliable (semi sphere ends).