Official Luthiers Forum!

I've been experimenting with different pore fillers. Currently working with Zpoxy on a Koa 000 sized that I'm building. One thing that I've noticed is that it is much darker than the System 3 that I used last. It seems to make the Koa much darker (and darker than the Koa appears with a bit of Naptha on it.

How careful do I have to be to make sure I sand it all back from the wood (and not the pores, of course)??

One note - I'm not using the Zpoxy on the top - just the back, sides and ncek.

Is there ever an issue with a "blotchy look" if I am less than successful in uniformly sanding the porefiller back before finishing (with KTM 9 in this case.)

Thanks.

Some people like to leave a layer of Zpoxy, or rather add a diluted layer of epoxy, after the pore filling is done. As you have noticed, Zpoxy has a yellowish hue, which is one reason this is done as some find it attractive. As an added bonus the epoxy will make the wood look "deeper", or give it a "wetter" look than almost any finish, at least more than waterborne finishes. I like to sand back to bare wood, and find that nitro or shellac gives much of the same wet look. And yes, there is definitely a danger that the wood will look blotchy if you don't sand uniformly back to bare wood.

_________________
Rian Gitar og Mandolin

-

Thanks for the replies - helpful.

I like shellac, so how about this for a process. After completing prep work, and sanding down uniformly (220 fine enough?) Wipe with a coat of dewaxed shellac. Then, after dry, apply a thin coat of Zpoxy - let dry overnight, then sand back to the wood. Zpoxy again, sand back again. One more coat of shellac, then KTM 9. Unnecessarily complicated? My reasoning is that if I mistakenly cut through the shellac to the bare wood, the last shellac coat before the KTM 9 will give it a uniform appearance.

One followon question. The Zpoxy finishing resin that I am using has a darker than "yellowish" tone to it - I"d describe it as almost a light cranbury color. I've been careful to mix it 50/50 with the hardener which is what gives it the color. Are we talkoing about the same stuff?

Corky,

Do a test to make sure that the z-poxy will stick/cure to shellac. I have not used z-poxy but I don't think the west systems I have been using will work over shellac. I have been thinking about doing the same thing you are proposing but with waterlox as the seal coat. I still have to make sure the westsystems will stick to that too. Whenever I sand back to bare wood I expose a pore or two and with any finish that sinks at all, it will eventually telegraph through. Not the end of the world, of course, but nice to able to avoid.

_________________
Burton
http://www.legeytinstruments.com
Brookline, MA.