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JJ, i would just give it 1-2 session of FP before buffing as a precaution maybe?

Well, certainly some epoxys dry harder than others. So if you are
using a hard glue and keep the final finish thin, it may not dampen
your acoustics. I'll stay tuned for the results of your experiment.

Rod...There are three characteristics that I'll be able to evaluate immediately:
1) The ability to wet sand and achieve that progressive sheen as it progresses to MicroMesh 12,000 grit.
2) The ability to take it to the next level on a buffer using Menzerna compounds (evaluating its heat resistance as you suggest)
3) Its toughness and scratch resistance

Over time, I expect to get a better idea on its stability and how it holds up to humidity and seasonal changes. I'll also know whether it can maintain a sheen and hold up to an occasional polishing.

Ken...good idea on a supplemental coating. If that's what is required then I'll consider the experiment less successful. Best case will be to have the ZPoxy attain and maintain an instrument quality surface finish on its own merits...I'm hopeful!

Sergio...I'd rather not have to use a FP'd shellac coating beacuse of it's fragility. Even though my tops are FP'd I'd prefer to have the body be tougher.

One other issue I have in the testing protocol...Having done a few Nitro finishes, the best results are achieved by allowing the finish to cure for at least 2 weeks before wet sanding and buffing. I plan to test this with ZPoxy by doing half of the body 2 days after the final coat and then waiting 2 weeks to finish the other half.

Thanks for the feedback. I was debating on whether to just do the trial and post the results along with the method once it was all completed... but I thought I might be able to get better ideas on how to pull it off by posting first. Even if it doesn't work, we will at least have learned something that may lead somewhere else.

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JJ
Napa, CA
http://www.DonohueGuitars.com

[QUOTE=JJ Donohue] I plan to test this with ZPoxy by doing half of the body 2 days after the final coat and then waiting 2 weeks to finish the other half.
[/QUOTE]

Good idea. I recall reading that WEST epoxy actually takes up to a month to reach full cured strength. The time required depends on the temperature as well, of course.
Keep us posted,please.
John

Right on JJ! I too am glad that you've decided to experiment... I'm lookin forward to the results.

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

Not all epoxies are equal, but I'm told by a rather sharp fellow I know (does composite and resin research for -big- aerospace) that epoxy resin is even harder than polyester, which is itself much harder than lacquer. Harder finish=better buffing results (barring extreme heat sensitivity)

The hard part, of course, is making sure you've got a layer of fully cured epoxy resin on your instrument rather than an uncured or semi-hard layer of 'something'. My experiences with cheap epoxies not fully curing have scared me away from using it as a finish on anything, but I'm eagerly awaiting the results of this experiment.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services