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Here's a couple questions:

1) I have read with some interest Mike Doolin's report that shellac sealer over epoxy will fall off like a grape peel unless you sand the epoxy filler back to bare wood. Has anyone else tried this combination without sanding the epoxy back to bare wood? If you have, what results? I have no reason to doubt that Mike suffered this problem, but I find it odd that no one else has reported any problems. Maybe no one else has tried it?

2) Has anyone tried using vinyl sealer over epoxy, again without sanding the epoxy back to bare wood? How did it adhere?

You may be able to tell from my questions that I think it is a pain in the neck to sand my epoxy filler back to bare wood if I don't have to. I don't put it on that thick, so it's doable, but I always prefer less sanding if I can get away with it.

I think Mike uses the epoxy as a filler sealer combo and sprays his waterborne finish right on that, not using any other sealer at all. I have used shellac over lightly sanded Z-poxy with no ill effects.

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I also have filled with Epoxy (west System) and then french polished with Shelac and it worked great.

I have used Zpoxy and as a pore filler and then sprayed either shellac or KTM9 over it without no adhesion problems.

Ditto what Arvey wrote. Guess I'm having a brain cramp, though. I thought Doolin stated just the opposite? That one could not put epoxy down over shellac? That's what's stopped me from using epoxy as a pore filler, cuz I'll usually put a wash coat or two of shellac down on an instrument just as a quick way to seal it.

Best,

Michael

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Live to Play, Play to Live

What Doolin said is that if you use Epoxy as a filler, don't use shellac between the epoxy and the KTM9, I have done this though and have not experienced any problems. I do however sand the shellac lightly before puting on the top finish. I also use a waterbased and dewaxed shellac. I am not using KTM9 anymore though because it's difficult to repair dings and such. It could be a problem with the particular epoxy he is using. I use z-poxy as a filler and I think he is using System Three epoxy.John How38612.7605208333

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Tickle your guitar daily, and it'll tickle you back.

I used Zpoxy, level sanded and applied Zinnser shellac right from the can before applying KTM-9. Lke John, I had no problems with adhesion of the finish.

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

Fact 1: shellac will adhear just fine to lightly sanded epoxy

Fact 2: Epoxy will not adhear well to a base coat of shellac.

So if you are planning to use epoxy for the fill, never use shellac as wetting agent on the raw wood prior to applying the epoxy. If you need to get a look at what the wood will look like with finish use naptha or minerial spirits,

never use shallac under epoxy!!!!!

There is no need to use shellac under the epoxy anyway as the epoxy will pop the grain like just about nothing else.John How38614.4583217593

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Tickle your guitar daily, and it'll tickle you back.

[QUOTE=John How] I am not using KTM9 anymore though because it's difficult to repair dings and such. [/QUOTE]
So John what is your finish of choice these days?

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[QUOTE=John How] I am not using KTM9 anymore though because it's difficult to repair dings and such.[/QUOTE]

Apparently John Greven is moving on from KTM9 to French Polish as well see here:

John Greven

Two European Countries replacing a Dr Who dog - no that was K9 (Sorry, that was an English joke!)Dave White38614.5671875

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Bob, the last two guitars I did were finished in McFaddens Nitro and Behlens Rockhard Table varnish. I am still playing with the varnish to see how best to handle that. It looks real nice though and it allows a much thinner finish. The bigest trouble I have had with it is just that, I buff thru.
I have also been talking with Addam Stark and may just send him a guitar or two when I get one ready.

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Tickle your guitar daily, and it'll tickle you back.

John I have some Behlens Rock Hard too. Havn't tried it yet. I'm pretty sure that's what Bruce Sexauer uses. Do you have issues with dust and the longer drying time?

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Beautiful and unusual tone woods at a reasonable price.
http://www.rctonewoods.com/RCT_Store
The Zootman
1109 Military Rd.
Kenmore, NY 14217
(716) 874-1498

No not really. You have to keep it isolated from dust for an hour or so but it's not bad. The last couple coats I have tried I sprayed and that seems to be the way for me as my brushing technique is not that good. I think the trick is in getting the right mix of varnish and reducer to get a good flow out. It definately takes some experimentation. Bruce told me to also add a capfull or so of acytone to help succesive coats burn in a little.

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Tickle your guitar daily, and it'll tickle you back.