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Hi all,

I've been using Crystalac grain filler for a little more than a year now. For most of it, it works great. But every once in a while I've had an issue that I can't seem to get ride of. The thing is that it seems impossible to see if you have sanded all the way to the wood, or if there is a thin film that remains. When applying the finish, that film shows up as some blotchy milky areas. So I have to sand those areas back and finish again, but since the darn film gets invisible once you start sanding it, you have to sand blindly, and you know if you done enough only when you reapply the finish. Most of the time, it turns out I have to completely scrape/sand and entire surface and start from scratch.

So my main goal is to find a way to pin point those areas where a film of filler remains before I start applying the finish. I've tried applying naphta to see if they would show, but that didn't work.

Any thoughts, ideas or suggestion?

Thanks.

Edit: As a complement of information, here's a picture of somebody's guitar body experiencing the same thing. (It's taken from http://www.marcelroy.com/mods/refins/refintips.html.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I tried Crystalac on 5 guitars with mixed results. Three worked great all the way through. On one rosewood back I saw milky blotches and had to respray after wiping down with thinner. Lucky it showed on the first coat of nitro.
On a mahogany back I was not able to fill all the pores with 3 applications. Looked good till I put the finish on. I must have sanded back too much exposing new pores.

Chuck

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I had mixed results too. Biggest problem area to me was the heel area of the neck. Seemed to always have a small splotch of the milky residue.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I had some milky looking places on some wenge purfs where the pores were huge the one time I used it.

Try adding a waterbase stain to the filler.
Something that will not color the wood;just show up better
when sanding.

Mike

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Mike Collins

Hey Mike,

That is certainly worth the try!

Thanks.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Hi all,

Just so people who may end up on this thread after a search on similar issues with Crystalac, I have found a solution which is explained here.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)