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.

               

I think you can find extruded aluminium tubing around 1 mm thickness in many dimensions (Outside diameter)

The ones we made for the air/water rockets, were turned down in my lathe from 45 mm outside diameter extruded tube, with 1,5 mm wall thickness.

This allowed us to leave the ends at 1,5 mm, since we originally wanted to weld the end cap and rocket nozzle on ..  However the welder we had could not weld this thin material ..
So we ended up bonding it with structural adhesive first, then winding the CF tow over the whole thing .. + the Kevlar braided hose .

The rocket still flies -- now they are running a two stage water rocket, and working pressures are up to 30 Bar now .. --  Silly kids ..

They have joined the "Amateur Rocket Club" and are working on chemically propelled rockets as well  . They are trying to convince me to build a CF nosecone for one of them ..

"Sapere Aude"... Dare to KNOW!

The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind...

103% of all people do not understand statistics...

Do not adjust our mind, theres a fault in reality :-)

Great story
The tank is now waiting all the air connectors before air pressure test. I have the feeling it is much stronger than necessary, and the challenge will be faced on connections... will see...