Fibreglass : Mold and Enclosure Making : How To and How Not To

Nobody that sells silicone so would be looking for a new supplier anyway.

Would brush on the jacket for a the fibreglass molds i reckon, and matrix for the urethane parts… will have a look at your link a bit later today :+1:

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The smooth-on link I sent says they have two locations in Australia. I have no idea if they are close though. For your brush on mold make sure you get some thixotropic agent or filler. How are you going to approach the matrix mold? You may need clay as well.

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Vac bag time!
Fingers crossed. Got nervous and included a plastic release layer between the layup and the mould. Hopefully that peels off the part.
2/200GSM carbon twill and 2/400GSM biax fibreglass.

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Nice bro! Looking forward to the result!

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Out of the mould…
Couple of dry spots
Some bubbles and pooling in a few areas
Plastic release layer made de moulding easy but made some small wrinkles in surface finish. Maybe sandable.
Lost quite a lot of crispness of the shape in the vac forming mould I think. Maybe more heat in next vac form and larger radius curves in next plug. Small detail wasn’t well replicated.
Might see how it goes with another layup direct on the styrene mould.

Polyester resin will eat through your styrene mould… not sure about epoxy.

Why don’t you just try a hand layup without the vac bag?

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Epoxy didn’t eat the styrene sample did a test on a few days ago. Did a small test with hairspray as release agent (actually seemed to work ok).

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Never heard of using hairspray as a release! Don’t think I would risk it tho…

It looks awesome dude! Just touch up the bubbles/dry spots/wrinkles with some more epoxy, sand it back, clear coat and you’ll be golden!

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Vac bag just pulls all the layers tight together and helps strength. Supposed to squeeze out excess resin. It’s not difficult to do so will probably do it with that again. Generally the surface finish on the flat parts of it are :ok_hand:

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Yeah, I’d heard of hairspray as an adhesive?

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Apparently it works really well on the print bed of a 3d printer…

But back in my hoodlum days we also used to use it on paper stickers as a ghetto weather proofer so :man_shrugging:

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Don’t mind me, i’m just jealous that I don’t have a proper vac setup… yet.

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It’s basically spray on plastic. I bought PVA mould release but have read that it can be hard to get a good finish using it unless you spray it and I don’t have that gear. Might try brush or wipe it on but expect I’ll get brushmarks.

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If you use a foam brush, you don’t get brush marks. And it is so watery that it flattens out anyway. The pva release is good stuff :+1:

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Oil free diaphragm pump
Vacuum control switch so it doesn’t run constantly.
Churrrr

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https://www.smcpneumatics.com/poweraire/Miniature_Pneumatic_Components.pdf#page15

Plus brass fittings and stuff from a gas fitting shop. Some one way valves.

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I used to use it to stick my BMX handlebar grips on!

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Some sanding done, and clear coat. Gave up the sanding and repairs on a couple of bits. The plastic release layer against the mould caused some areas of the fibre to sit slightly off the mould during layup but then fill with epoxy when I vacuum bagged it. Thick epoxy layer then formed unevenly at those tight corners. No major, try again another time maybe without that release layer. Happy enough with this though. Chur.

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You should be happy! It looks sweet as bro!

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That looks great. It’s one of those things where to an outsider looks damn near perfect but the creator an point out all the flaws.

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