Talk Composites - The Forum for Advanced Composites

Making a CF tube 114mm dia

http://www.talkcomposites.com/Topic2322.aspx

By stuart321 - 7/20/2012 11:19:33 AM

Hi,

Any advice on how to make a nice looking snorkel (straight tube) out of CF its 4.5" (114mm) outside diameter and 4" / 100mm long.

I tried wet lay-up round a sacrifical former with vac bag film over the top taping round it to provide some tension.
The layers consolidated fine, result is ok but not super smooth (although I haven't gelcoated it yet).

I could make a mould at 117mm id but I expect it would be hard to neatly place 3 layers of CF and then a pain to vac bag.
I could retry the former route and seal it to pull a vacuum (former would need to be fairly strong I guess which would add to the release challenge).

Is it feasible to get a good finish with wet layup and vac bag film pulled tight round the part?
Its not really on show so maybe I'm being over fussy.

Any views appreciated!

Thanks
Stuart
By stuart321 - 7/20/2012 10:35:22 PM

r0bsk1 (20/07/2012)
Try going at it in the other direction......
Get a pipe with the ID of what you want the CF to be and slice it in 2. apply release agent.
Get a car inner tube and slightly inflat it.
Wet the carbon and wrap it round the inner tube. You might need some vac bagging release sheet to aid release from the inner tube later
Get the 114mm pipe and put the 2  halves around the carbon.
Secure the pipe so it cant come apart.
Now inflate the inner tube more.
Allow to cure.


I can see that working - agree on the film round the inner tube - the epoxy resin seems to stick well to most things!

Thanks
Stuart