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Fibreglass plug paint problem

I'm currently working on a project were I'm making a mould of a spherical garden ornament. The garden ornament is the plug, I filled, sanded, painted and smoothed it, then I applied several layers of release wax and then PVA. When I applied the fibreglass it caused the paint to soften and blister, and it peals away when I try to remove the fibreglass mould.

I have tried using car bodywork repair paint, the high build type that is easy to sand, I also tried ordinary household vinyl emulsion. Both of these have caused the same problem.

Could anyone tell me what type of paint won't react with polyester resin, that I can obtain in the UK?

Other postings have mentioned Duratec but we don't seem to get that in the UK, is there a similar product I can get here?

Others have mentioned polyurethane or polyester paint. Can I get these in B&Q or Halfords or online somewhere? Is melamine paint viable?

Cheers for the help.

Ivan

Reply to
Ivan
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Why not use epoxy? After it has cured, practically nothing will react with it. You don't mention which type of resin you are using for the fiberglass mold, but I'll guess that it's polyester rather than epoxy. The solvents used with polyester resin are far more reactive than the epoxies.

Jim - AMA 501383

Ivan wrote:

Reply to
James D Jones

Use gelcoat........spray....... sand............buff........wax........stay away from PVA then build your mold with a gelcoat base to start.

frp

Reply to
FRP

Hi Ivan, I feel for you. It's frustrating isn't it? Anyhow, here's what you should do next time -

Use ONLY Nitro-cellulose Lacquer as the final coat on your plug. I've heard that Acrylic Lacquer is also ok but I've never used it. In the colonys, its marketed as ICI (Imperial Chemical Industry) DUCO. Apply Duco in thin coats letting each coat flash off before the next coat (abt 3 mins in the tropics) then one thicker flow coat. Then its done. Let the paint harden for at least a few days until there is absolutely no smell of thinner when you put your nose to the plug. Then and only then do you apply wax. If you're feeling rich, you can also use epoxy paint and most 2 pack paints but I don't have personal experience with these. But I dare say that a harder paint will make the demoulding easier since Duco is somewhat softer and MAY deform slightly under mould shrinkage. But I've not had major problems with duco. But you also must make sure that there are no soft spots under the paint or the mould will shrink into those soft spots making the mold surface less tahn perfect.

email me directly if you have more questions.

cheers Arnold

When I applied the fibreglass it caused the

Reply to
YSTay

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