Minute Gap Filling

[Harvey Pascoe]

Still looking for the perfect solution. I make fancy boxes with designs on the top from thick veneers, usually with a lot of stringing. Then I try to produce mirror smooth varnish finishes but I'm always stymied by minute gaps where the glue does not completely squeeze through the seams so I am reduced to using a fine artists brush to laboriously fill the gaps with numerous applications of varnish and then sanding it down. These gaps are small enough that they don't really show when filled, like 1/64 - 1/32.

My question is whether anyone knows of a rapid curing clear filler that is easily sandable. I've used epoxy but that is unacceptable because of its lack of sandability. You'd think with all the ballyhoo about technology, someone would produce a product like this.

[David Hawxhurst]

i've had success mixing glue and saw dust.

[Chris Fournier]

While I do find them a bit of a pain, burn in shellac sticks come in many colours and are sandable once they cool. Perhaps these could work for you Harvey?

[John TenEyck]

Have you tried SuperGlue? It comes in different viscosities and one of the gels might do the trick for you. I would use it after your sealer coat is on so that it doesn't wet into the wood on either side of the crack and change the appearance under your topcoat.

[Jim Becker]

Harvey, I've often used "super glue" as a filler on turnings in exactly the way you are asking. I have both clear and black CA for that purpose.

[Howard Acheson]

I would try SuperGlue. Use a scraper to level rather than sandpaper. The glue being harder will tend to sand slower than the surrounding wood leaving you with a raised repair. If you use a scraper to level, you will end up with a leveled repair.

[Rob Cunningham]

I've used medium or thick super glue for small cracks. I keep small containers of sawdust from various woods to fill the void if necessary, then apply the super glue.

[Jim Finn]

I fill those minute flaws with a mixture of Elmers white glue and wood powder from my orbital sander. Use just enough powder to color the glue. Rub in and sand off after about an hour.

[Harvey Pascoe]

Thank you all. Actually I have used CA gel but I got one of those (gad) 0.14 oz. bottles for $4 and it disappeared in no time so the cost there was daunting. I will assume that it is available in larger amounts at a more reasonable price? And that it won't cure in the container within a few weeks?

I specified clear because I use varied color inlays ( like ebony, satinwood and rosewoods) against which PVA glue in any form sticks out like a sore thumb. I've even colored it with various pigments, but when I lay the finish over it the damn seam just pops right out visually. Clear epoxy would be perfect but for its sandability and my being highly allergic to it. Anyhoo, I'm going to give CA gel a shot, sounds good.

BTW, you may be able to get better color matches using pva glue by using water colors. Buy a cheap set and you should be able to get better matches than with sawdust once you get the knack of mixing colors.

[Scott Holmes]

Chris and I agree again!

Shellac sticks and a burn in knife. Showed somene today how to do it. Filled a hole in my workbnch to show him the technique.

[Harvey Pascoe]

Chris and I agree again!

Shellac sticks and a burn in knife. Showed somene today how to do it. Filled a hole in my workbnch to show him the technique.

First off, what is a burn in knife? Secondly, what kind of coloration would shellac sticks give to a wide range of colored woods? For example, golden Ceylon satinwood against black, black ebony is a tough one as anything but black against black stands out, while clear is far less visible. Thanks.

[Chris Fournier]

http://www.leevalley.com/en/wood/page.aspx?p=42999&cat=1,190,42997&ap=1

There are plenty of other places to get this stuff but here's a visual answer to your question.

[Steve Schoene]

You only have to match the color of the wood on one side of any gap. Matching that one will just extend it's shape to the otherone. Yes, this means you may need a lot ofcolors, but shellac sticks or similar fillers are available in a very large pallet of colors. Check out Mohawk products. You can get a catalog and color chips that will be helpful. You will likely need to find an on-line dealer to order products since the company itself has fairly large minimum direct orders.

[Harvey Pascoe]

http://www.leevalley.com/en/wood/page.aspx?p=42999&cat=1,190,42997&ap=1

There are plenty of other places to get this stuff but here's a visual answer to your question.

Yeah, thanks Chris, I found that in my catalogue.

Steve, you're half right. I just did that yesterday and it looks good to one side but shows on the other. This was ebony to satinwood, i.e. black to yellow. The gap was about 1/32, a bit too large. . There isn't anything that will produce an invisible filler, not even clear. The other problem is with a pigmented filler, it is going to stain one or the other pieces of wood since its either lighter or darker. I rather quickly came to the conclusion that the only effective solution is to be more precise and avoid any gaps, a rather tall order for what I do. Sigh.

[Harvey Pascoe]

You only have to match the color of the wood on one side of any gap. Matching that one will just extend it's shape to the otherone. Yes, this means you may need a lot ofcolors, but shellac sticks or similar fillers are available in a very large pallet of colors. Check out Mohawk products. You can get a catalog and color chips that will be helpful. You will likely need to find an on-line dealer to order products since the company itself has fairly large minimum direct orders.

When I am mating Ceylon satinwood with ebony, or similarly high contrasts, any colored filler sticks out like a sore thumb against one wood or the other. And believe me, I've tried every method.

Just to update this thread, I finally got a large tube of CA gel and I can now say that it works great for filling those tiny crevices in advance of creating a mirror finish. Completely invisible under the finish. Even if the gap is fairly large, say 1/64" and may be visible, it looks far better than any colored fill.