Clear hole filler?

[Jim Andrew]

About 40 years ago, when I was an industrial arts student, one of the teachers was using polyester resin to fill holes in wood, took several coats painted on with a brush, but then you just sanded it down and went over it with clear finish, and when you were done, the surface was even, but it looked like glass over a defect. Would like to do that with some holes in my panels, but don't remember the whole process. Is polyester resin available in small quantities, and do you mix hardener with the stuff? Anybody else interested in this process?

[Rob Sack]

Try CA glue with a very thick viscosity. If you use an accelerator, it will dry almost instantly.

[Jamie Buxton]

Polyester resin is available. It is the standard resin for fiberglassing. Even my local Home Depot has it. However, IIRC, HD only sells it in a gallon. An alternative is epoxy resin. You can buy it in many woodworking sites -- for instance Woodcraft. You can buy smaller amounts than a gallon. West Systems and System Three are the big names in epoxy.

Both polyester and epoxy are two-part things. You mix a hardener with a resin. In epoxy, you can buy hardeners of different speeds. Both epoxy and polyester are naturally clear; you have to add pigment to make them colored.

[John Coloccia]

Generally, the only reason to use polyester resin is that it's cheaper than epoxy. If you're building a boat or an airplane, you can save some bucks. Polyester is also tricky to mix...you literally use little drops of catalyst for large quantities of resin, and the catalyst is ultra nasty. Lookup MEKP. It's difficult to imagine a nastier chemical that is readily available for home use.

CA works, but you need to be careful with accelerator. Use a touch too much, and it will foam and turn white. Make the repair too deep, and it will skin over and take forever to cure. Relatively thin layers with little to no accelerator works best.

FWIW, ZPoxy finishing resin (made by Pacer) has become a favorite for guitar builders as a pore filler because of how well it sands. System 3 and West also make fantastic epoxies. System 3 in particular has one that is extremely clear and colorless.

[David Hawxhurst]

us composites sells several diffrent kinds of epoxies and polyster resins. the have there own branded epoxies (thick or thin) that are comparable to west and system 3 and cost a lot less.