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Acrylic sheet as mould

http://www.talkcomposites.com/Topic37973.aspx

By macgtech - 9/22/2020 7:47:38 AM

Hi guys

We typically use polyproylene (PP) sheet for moulds for ducts, floors etc and other aero parts on the racecars - we have various line benders and forming tools to form the PP to the shapes required, and it obviously releases well with no release agents and gives a great surface finish. 

My question is, will acylic sheet behave the same in terms of release behaviour for epoxy? Our PP supplier is struggling to get the material in and we can get acrylic very locally at a good price. The acrylic material is also stiffer so would not need as much reinforcement as the PP which also helps, and is a little more scatch resistant. We can  obviously give it a try but figured it would be easier to ask on here first in case someone tried using acrylic sheet before.

Thanks

Jonny
By Hanaldo - 9/22/2020 11:51:15 PM

nigelhill - 9/22/2020 8:01:54 PM
macgtech - 9/22/2020 7:47:38 AM
Hi guys

We typically use polyproylene (PP) sheet for moulds for ducts, floors etc and other aero parts on the racecars - we have various line benders and forming tools to form the PP to the shapes required, and it obviously releases well with no release agents and gives a great surface finish. 

My question is, will acylic sheet behave the same in terms of release behaviour for epoxy? Our PP supplier is struggling to get the material in and we can get acrylic very locally at a good price. The acrylic material is also stiffer so would not need as much reinforcement as the PP which also helps, and is a little more scatch resistant. We can  obviously give it a try but figured it would be easier to ask on here first in case someone tried using acrylic sheet before.

Thanks

Jonny

I use perspex with dragonskin30 silicone without release agent and it works perfectly. I've used KX Flex urethane with release agent and had no issues. I didn't test that one without release agent.

Silicone doesn't need a release agent, it doesnt stick to anything except itself and other silicones. 

If you use the right release agent, acrylic can work with epoxy. As Lester said, it is very sensitive to solvents, so you need a release agent with very little solvent content - I've used TR-108 release wax, as well as PVA (separately, not together) to good effect.

No where near as nice as polypropylene though. I've been bitten by acrylic a few times, so I try to avoid it these days.