Composite moldings

richard_sykes · 12 Jul 2005, 20:30 (Ref:1354066)

I have been playing around with some carbon fibre and kevlar I bought off ebay, along with some of the epoxy I bought to sort a few things out on my sailing dinghy.

But, I need to make some molds for gauge pods and a few carbon clamps under the bonnet. I cant find anywhere that sell a foam like expanded polystyrene locally. Any ideas where to look, art shops dont seem to have it around here?

All sorted: mod can delete

Chucky · 13 Jul 2005, 02:58 (Ref:1354292)

Air conditioning supplies.

THR · 15 Jul 2005, 19:35 (Ref:1356476)

ask a university???
they helpful usually.
or email ummm the people that sell the stuff? google search time!!!

RS sell that sort of stuff, or honeycomb

richard_sykes · 15 Jul 2005, 20:24 (Ref:1356509)

Thank you, the real stuff if you search for modelling foam is ridiculasly expensive.

If anybody is interested in smaller sheets of carbon cloth, there is a seller in the US on Ebay, $120 delivered anywhere in the world. He only takes a week.

MountainRunner · 9 Aug 2005, 05:21 (Ref:1375463)

Fibre glass suppliers usually sell the foam in sheets or as two part liquid that you can mix yourself.

richard_sykes · 10 Aug 2005, 16:22 (Ref:1379134)

I been using flower arranging foam bricks.

Called Oasis apparently

Bishop Ranter · 17 Aug 2005, 11:13 (Ref:1384504)

Composites is a specialist activity within Cranfield University which also operates the FIA sanctioned Cranfield Impact Centre http://www.cicl.co.uk/racing.htm

The technician in the Composites Department Jim Hurley (j.hurley@cranfield.ac.uk) is a really helpful person who used to work in motorsport.

In addition to the MSc Motorsport Engineering and Management http://www.motorsport.cranfield.ac.uk/course.htm the University runs specialist short courses such as:

Composite materials for motorsport http://www.motorsport.cranfield.ac.uk/ammnm.htm

Composites (1): materials and processing
http://www.cranfield.ac.uk/sims/mate...processing.htm

Composites (2): mechanical performance
http://www.cranfield.ac.uk/sims/mate...mechanical.htm

Polymer Engineering
http://www.cranfield.ac.uk/sims/mate...ngineering.htm

Hope this helps.

richard_sykes · 17 Aug 2005, 14:30 (Ref:1384687)

Thank you, some good info in there !

scarbs · 18 Aug 2005, 12:50 (Ref:1385511)

Try asking here...

http://www.netcomposites.com/Forum/S...spx?ForumID=21

JohnD · 22 Aug 2005, 11:40 (Ref:1388224)

Richard,
I've used polyurethane sheet, that I got from a local GRP fabricators (FiberForm, Lancaster). It works easily, can be made into blocks by layering it with resin and takes a glass-fibre skin well. Problem is that it absorbs a lot of resin and the part ends up rather heavier than you would wish. I've no experience with it and carbon-fibre or kevlar, or an autoclave.
I've had more success using paper honeycomb (Dufaylite), as alloy honeycomb is out of my budget range. 'Glue' the honeycomb to the skin with polyurethane foam - the type used by house builders for filling voids, comes in an aerosol. Saloon roof 9kgs, Doors 5kgs each.

John

Ntrprise · 22 Aug 2005, 13:14 (Ref:1388334)

Where are you based? I have brought off a company based just outside of Bracknell. They are mostly a Fiberflass workshop..... But because they buy at trade prices - they sell onto me (and I guess anyone else that asks) at a price that is inbetween trade and what other people sell it for.

I'll dig out the contact details and provide tomorrow. But they are very helpful and friendly and have stopped me from making some costl errors

I feel like I owe them --- hence the recommendation

JohnD · 23 Aug 2005, 11:58 (Ref:1389223)

Ntrprise,
I'm in North Lancashire (Lancaster?) so Bracknell is a bit out of my way. But what are you buying from your contact - not alloy honeycomb by any chance? How much??
John

richard_sykes · 23 Aug 2005, 19:09 (Ref:1389604)

You been makeing doors? Or just skins?

I been buying off a atomik fabirks, mainly carbon fibre braid.

Bought a big sheet of carbon of ebay from the sates recently but it is yet to turn up.

JohnD · 23 Aug 2005, 20:45 (Ref:1389690)

Complete doors, roof, tailgate, in GRP, not carbon. Because the tailgate includes the window frame, I made it by layering P/u foam onto the outer skin, and skinning that with GRP. The doors are GRP skins with paper honeycomb and an internal skin inside. Though a door is about the same size as the tailgate, without the glass (polycarbonate), the latter is about four times heavier, due to all the resin absorbed by the foam. Next time, I'll use honeycomb - the composite is quite strong enough!

An autoclave is never going to be cheap enough for an amateur. How are you curing your carbonfibre resin? And vacuuming the layups?
John

richard_sykes · 24 Aug 2005, 09:43 (Ref:1389978)

I do it in the garage, have a old heater electrical heater if its cool.

I use SP systems Ampreg 20 mainly becuase I started making bits on a sailing dinghy that was costing silly money to maintain.

By the way the carbon fibre turned up this morning, its very light in colour and says graphite carbon fibre. Can anybody elaboriate on what/why this is?

With vacum bagging, I found a good site some months ago mainly for motorbike bits beeing produced at home.

http://www.resin-supplies.co.uk/resi...#EPOXY%20RESIN is another UK supplier (have not used these yet)

Rich

JohnD · 24 Aug 2005, 12:26 (Ref:1390135)

Richard,
Thanks for that contact!

I get all my suppleis from my local fabricator. The boss is most friendly, willing with advice and, of course, to sell me materials. I can get from him what I don't see on that site and what I consider essential for motorpsort applications, flame retardant resin to Class 1 ASTM E 84.

How fire vulnerable are carbon fibre panels?

John