Gel coat and Epoxy if done correctly will it work?

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Gel coat and Epoxy if done correctly will it work?

Gel coat and Epoxy if done correctly will it work?

Author	Message
fastboats	fastboats posted 10 Years Ago HOT Topic Details
Group: Forum Members Posts: 9, Visits: 94	Looking to make a mold of a small performance boat hull. I have read that in order to make a very good mold that will last a long time some use carbon fiber vs fiberglass mat in a unimold type setup. Once the part is setup and flanges in place can I apply gel wait for that to tack and apply a layor of carbon down and expoy coat over that? Or will the Gel delaminate from the mold? Thanks for any help and please go easy I'm new and learning as much as I can. Edited 10 Years Ago by fastboats
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wojtepanik	wojtepanik posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 102, Visits: 582	you use carbon same as glass fibers. in poly resin watch for wax contamination on surface, it depends on product, that you should apply backing layers when gelcoat is tacky, not fully cured. It does not happen while epoxy is in da game Bye ~~~Everytime I hear sound of demoulding part I have eargasm~~~
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Dravis	Dravis posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 592, Visits: 1.9K	Are you talking about "mixing" Unimould Gel-coat with epoxy for backing?? That will probably not work at all .... As far as I'm aware the Unimould Gelcoat is a Vinylester type. If you want a very stable and shrink free "-dimensionally stable" mould, then use an all epoxy setup, with CF and Glass reinforcement. While the Epoxy gelcoat will not polish up as nicely "mirror-finish" as the Polyester/vinylester Gels, it will be very strong. "Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	I'm not certain that it wouldn't work... I've used epoxy tooling gelcoat and backed it up with vinyl ester laminating resin, that works very well. Vinyl ester and epoxy tend to work very well together, so I wouldn't be surprised if it could be done.
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Dravis	Dravis posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 592, Visits: 1.9K	Yes, but I think that has to do with what will bond to what, and in which "state" Both Polyester and Vinylester gelcoats will stay tacky, when exposed to air, and Epoxy will not bond properly to those in a tacky state, unless they are specially formulated to do so (Like the GC50 gelcoat) Adding wax additive to handle that will definitely prevent the epoxy from bonding to the Gelcoat-- Also the point of using Epoxy and CF for the mould is to make it dimensionally stable (no shrink) that usually means using an all epoxy setup. But, maybe one could use the Unimould Gelcoat, with epoxy backing, it may be worth a test The EC tech guys may have some input to this ? "Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Yeh that is my one doubt... But I'm not so sure that wax additive would be a bad solution. Once cured, a quick wipe with acetone would remove the wax build up. Normally that would make the gelcoat vulnerable to attack from subsequent layers and alligator, but epoxy wouldn't do that, so it should be ok. I also don't think there would be much difference in terms of shrinkage between an all epoxy mould and a mould with a vinyl gelcoat and epoxy reinforcement. I'm obviously just speculating here, I suspect Dravis is probably correct about the vinyl remaining in an open state and the epoxy not bonding to it. I do think it would be worth a test. Edited 10 Years Ago by Hanaldo
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fastboats	fastboats posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 9, Visits: 94	OK I found GC50 clear but I want black can I add color somehow? Add a pigment or spray clear and then paint a color? I was hoping to use a colored gel so I could just brush it onto the part/mold. Edited 10 Years Ago by fastboats
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fastboats	fastboats posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 9, Visits: 94	Edited. Edited 10 Years Ago by fastboats
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kidpaint	kidpaint posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 99, Visits: 676	sorry to thread jack, but if im reading this right. You can use epoxy gelcoat and follow up with VE resins to do the fiberglass lay up?
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Correct. Just watch for styrene attack. If the epoxy isn't sufficiently cured, the styrene can prevent it from curing and you'll pull a sticky mess. Edited 10 Years Ago by Hanaldo
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