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Wendy--

That is good news! Yeah, clearing with just alcohol only goes so far. The alcohol eventually evaporates, leaving whatever was there before you put alcohol on it. In other words, white/grey pumice, if too much of it is together with nothing else. In the traditional method, I think the alcohol "clearing" the pumice is more about saturating the pumice with alcohol so that the shellac gets dissolved better and mixes better with the pumice and sawdust. Whatever happens, once the alcohol evaporates, what is left is shellac, pumice and sawdust. That much is plain.

So, it sounds like the pumice acts like a thickener to the shellac. It "clears" and stays cleared as long as it is mixed in with the shellac. That's cool! I might have to try that.

Of course, what that means is that your mix of shellac, pumice and sawdust is mostly shellac and pumice, and not too much sawdust. My speck problem was, no doubt, caused by too much pumice and not enough of the other two.

I am looking forward to trying the Robbie O'Brien thing I mentioned above: sawdust and shellac, no pumice. I might also experiment with your shellac and pumice, little sawdust method.

Lots of interesting possibilities!

Really simple method. 2 coats of egg white, first coat left to dry before applying second. Once all dry, lightly wet some 320 wet and dry then lightly sand (I sanded in circles, and it went OK, but across the grain rather than with the grain) until the slurry starts to fill the pores. Perfect colour match on the wenge but not sure how it would be on lighter wood.

Test on a scrap board to perfect your technique. You can get a feel for when you have too much water and when the slurry is too dry.

Have fun.

When I pore fill with egg white, I just put the egg white on and sand until there is a slurry then press into pores, let dry sand back. Repeat.

_________________
Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Also, I find it helpful to do small sections at time.

_________________
Jim Watts
http://jameswattsguitars.com

I like to think of the pumice as an abrasive too that way you are keen on not using too much of it. When done properly it even sounds like you are sanding the wood. I suppose you could use sand paper but you would still need to use alcohol regardless and the muneca has a nice way of controlling that.

Burton wrote:
"After experiencing some dermatitis from epoxy I never want to have to sand it again! Especially if something else works."

Allowing epoxy to cure for a couple of weeks before sanding may cut down the risk of developing dermatitis. A small percentage of the epoxy never cures, so safety precautions should still be used.

Has anyone tried using Bondo as a pore filler? Mohawk sells a "wood" colored bondo (and a white colored hardener) that can be colored using powered pigments. It might be worth a try.

In my view one of the paramount characteristics of a good pore file is "easy to sand" -- both regular, Bondo and Bondo two part wood filer(gold color) become rock hard in a day, even if you could get a good color match, which I think would be difficult I would not use Bondo for this purpose. However its great for tool and fixture making.

_________________
Ken Cierp

http://www.kennethmichaelguitars.com/

And at the end of the day, you don't have to throw away a pile of used sandpaper...

So how'd the test turn out? Any major shrinkage or white specks appearing, or is this a confirmed good method for pore filling mahogany?

Dennis, after 1 week there appears to be some shrinkage, not much more than I think a 2nd coat wouldn't take care of. No appearance of white specks though, seems to be pretty clear. I compared it to a sample that I did with Aqua Coat and the appearance is the same, other than a little more shrinkage with the pumice/shellac mix. I definitely think it is a method worth trying. In the meantime though, I decided to go ahead and fill with Aqua Coat. I just got impatient and wanted to get on with it. After a number of coats I finally got the hang of how to use it so I wasn't pulling it right back out of the pores or bridging them. I'm pretty happy with the results, although the pores are not filled 100%. Maybe epoxy would fill 100% but I have had enough problem reactions to fumes that I don't want to go there. I may do another coat of shellac/pumice mix on the sample this weekend just out of curiosity and see what it looks like in another week. If I do, I will let you know how it turns out.

I had a quick try of the shellac/pumice mix yesterday. After it dried. . . . white pores or at least visible signs of the pumice. Calling it 'White' would be taking it to the extreme. Initially it clears but after drying I started to see signs of the pumice. Kind of a dirty looking greyish brown. Very visible in respect of the surrounding wood.
But this was with Walnut, 3F Pumice and a Blonde shellac. Of course with Rosewood you may get a completely different experience.
I'm now pretty sure this is the reason why I never went on to use the method when I tried it many years ago. I tend to use Walnut frequently. Getting a good colour match for Walnut is a little more difficult than with a darker, oily wood like Rosewood.

If you do the same with Oil it clears the pumice and clears it for good, no doubt something to do with the index of refraction or some other technical term that I don't quite understand.

Michael, it looks like you put the pumice on the surface first and then add the oil? When I used the pumice/shellac I mixed 3F pumice with blond shellac until it was like a thin cream consistency. Then I applied it with a piece of cloth in circular motions. Then I sanded after it set up with 320. If I remember, there wasn't a lot on the surface. Most had been pushed into the pores. I'm still not seeing any white in the pores and it has been almost 2 weeks. I have not tried it on Walnut or Rosewood. Just on some figured and very porous Mahogany.

That's how I do the Oil. It probably doesn't matter if they are mixed before putting it on the wood.

I did the Shellac differently, the way you described. I've tried it before, some years ago. Don't ask me why I ended up with different results but I did. Sometimes it can be one slight difference which changes the outcome, which is why I always state that these things should be tested on an off cut first. Mostly these tests take just a few minutes to do. I didn't have to wait long before the pumice started to show, an hour or so. Try it on a much darker wood. I didn't sand my test and nor did I apply it in circular motions with a cloth. I used the squeegee method. Maybe that was the difference.

Hmm, maybe it just works for mahogany, or maybe it was just a fluke. I might have completely different results on a dark wood. Thanks.

Only one way to find out. Try it! Takes but a few minutes.