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So far I've:

1. Filled pores with epoxy. Two applications.
2. Leveled the final fill coat.
3. Wiped on epoxy to take care of the sanding blotches. Didn't dillute the epoxy and it worked great.

There are TINY ridges from the wiped on coat.....barely visible. The wood is otherwise perfectly flat and the epoxy is pretty smooth to the touch.

What grit do you consider best in order to create a good bond to nitro top coats without a shellac or vinyl intermediate coat? Does 400 have enough tooth? Would green Scotch-brite create enough tooth?

I prepared several test pieces using this epoxy pore fill method. I'm waiting on some EM 6000 to arrive.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Cant say for EM6000 .. but I scuff with 280 with nitro ...

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I scuff sand the epoxy with 300 grit until the ridges are gone. I couldn't tell from your post if you're top coating with nitro or EM6000. I've used both and prefer the EM6000 right out of the can. Flows beautifully, sands great and repairs just as easily as nitro (damhik). Good luck.

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Jimmy Caldwell
http://www.caldwellguitars.com

I think the green scotchbrite might be too much. Gray would be a better choice - more work - but a better choice.

But on a different note - I THINK you might need a seal coat between that epoxy and the topcoat. I can't give you any data to back that up because chemistry was not my forte. Some additional research might be worth the effort.

Good Luck to ya Brotha!
Chris

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

The ridges came with the wipe on coat. I bet they measure no more than .0005" high so the thickness of the topcoat will easily bury them. I expect they need to be removed however, if not just to guarantee they won't show underneath the topcoat.

Incidently, Todd. You said to reduce your epoxy for the wipe on coat 50/50 with denatured alcohol. When I did that my epoxy took many days to finally cure. Is that your experience? If not, what epoxy are you using?

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

My take on epoxy pore fillers. Fill the pores with epoxy, sand down down to bare wood. The pores are filled with epoxy at this point. Two wet coats of vinyl sealer, level sand and re-coat if needed. Then spray nitro. Wiping on a thin coat of epoxy sounds great but if you ever sand through it accidently, you will have a light spot in yor finish. I have done 3 guitars with epoxy/sealer/nitro. The third was sanded down to wood after pore filling and it looks the best by far. As tempting as zpoxy or any epoxy makes the grain pop, with a thin coat, the sealer and nitro coats are just as good.

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John Nowicki

I'm with John on this, but without the vinyl sealer. I just use a wash coat of shellac. If you're going to use a thin coat of epoxy I don't think there's any need to sand finer than 220 grit. Adhesion would probably be better than going finer, and I'm pretty sure Nitro, or EM6000 either one would take care of the 220 grit scratches. In other words, sanding finer than 220 grit may not cause problems, but I don't think there's any benefit either.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/