Carbon fiber roof - making the mold

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Carbon fiber roof - making the mold

Author	Message
BlackNDecker	BlackNDecker posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 92, Visits: 251	This was my stopping point when I ran out of resin: I used 1/4" chopped glass fibers mixed with resin to fill the corners all around the perimeter.
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Jacopo Carbonio	Jacopo Carbonio posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 43, Visits: 109	How many "layers" of wax did you used? I follow your project with interest
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BlackNDecker	BlackNDecker posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 92, Visits: 251	I laid down about 4-5 coats of heavy wax. I think this will be enough since this is a brand new, blemish free steel roof.
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Is that bridging all along the back edge or did you use a filler of some sort?
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BlackNDecker	BlackNDecker posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 92, Visits: 251	I used a slurry of chopped glass fibers mixed with resin and worked it into the corners all the way around.
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BlackNDecker	BlackNDecker posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 92, Visits: 251	Sanded the whole mold down and filled some voids with Duraglas...
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Looking good.
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BlackNDecker	BlackNDecker posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 92, Visits: 251	Thanks. I think I'm going to smooth out the transition all around the perimeter with long-strand kitty hair putty. I think this will make it easier to lay down the CSM without voids. Has anyone ever attempted this in the mold lay up?
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	A lot of effort to go through for little reason. Firstly, the first layer behind the gelcoat is the critical one that you don't want voids behind. The gelcoat is what needs the support, after that first layer any voids in the mould aren't too critical. Obviously this is within reason, you don't want large areas of bridging or large/lots of voids. But regular laminating techniques, so good stippling with the brush and then going over the entire mould with a roller, will ensure that those voids don't occur. Secondly, you haven't got any angles there that 450g csm couldn't easily conform to. In fact, I don't see anything there that even a 850g couldn't cope with, with a bit of rolling. Smoothing that transition out isn't worth the time and effort you out into it. Just go on with the csm. If I might make a suggestion, that panel is quite large and flat. So I think you will find that the usual mould layup of 4-5 layers of 450g csm will still be a bit flexible. Couple options you have, one is just to live with the flex and hope it doesn't flex under vacuum and result in a distorted panel. Another option is to put a few extra layers of 450 on. But what I would do, to save resin/expense/weight, is do 2 layers of 450g csm and then 2 layers of 850g woven rovings, followed by another layer of 450 csm. Let that cure, then if it still isn't rigid enough, laminate some stiffeners onto the back (12mm mdf is my choice, can also use cardboard tube cut in half, coremat, etc) in the direction of the flex. Not sure if EC have 850g woven fibreglass, they might not. In that case just go with 5-6 layers 450 and then the stiffeners on the back if they are needed.
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BlackNDecker	BlackNDecker posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 92, Visits: 251	Thanks for all the help. I took your advice and applied two more layers of heavy CSM then heavy weight canvas I bought at the local hardware store. Edited 10 Years Ago by BlackNDecker
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