Sanding dust & glue to fill slight gaps?

[Bruce Page]

I’m making some finger joint boxes that have small gaps in a few of the joints after glue up. I would like to try to fill them with the sanding paste trick but have no idea how to mix & apply. I collected a small cup of the sanding dust.
Any advise would be greatly appreciated.

Thanks

[Nick Decker]

Ha! I just finished doing exactly what you're asking about, and it's even on finger joints. I don't know if there's a magic recipe for proportions. I just started with a small puddle of glue and a small pile of sawdust. Kind of just moved a little of each together and stirred until I had a fairly stiff paste and pressed it into the voids. Maybe 2 parts sawdust to one part glue? Let it dry overnight, then sanded.

I like this trick as long as you don't plan on staining. Once glue is involved, forget stain.

[Bruce Page]

Thanks Nick. If you did some glue repairs on that joint I sure can't see them.

[Victor Robinson]

Agree Nick, that turned out practically invisible.

[Nick Decker]

This was my third attempt at finger joints (not counting several "scrap" joints just learning the iBox jig). While I can't point out the exact areas of repair, I know there were several places on every corner of that box. Some were where the joint left small gaps, some where there was a bit of tear out from the router bit.

[Matt Day]

I’d caution the glue/dust method. Every time I’ve tried it, it sticks out like a soar thumb after finish is applied. I suggest inserting thin shavings if possible, or using wood filler like Timber Mate or Famowood.

[Nick Decker]

Matt,

I haven't applied any finish yet, so you may be right.

I've used Timbermate before and sometimes like it, but have sometimes seen situations (cracks and crevaces) where it hasn't adhered well. Also, I don't think they make a color that would match Padauk.

I took some closer pictures that show inside and outside of the same joint, to show the exact area that was repaired. I think this situation works better for glue/dust because the end grain that the repair abuts is naturally darker anyway.

[Mike Henderson]

I’d caution the glue/dust method. Every time I’ve tried it, it sticks out like a sore thumb after finish is applied. I suggest inserting thin shavings if possible, or using wood filler like Timber Mate or Famowood.

I insert thin pieces of wood, also. If you do them so that the wood and the thin piece are end grain they're essentially invisible.

When you mix sanding dust (or sawdust) with glue, the mixture is darker than the original wood. In many situations, the wood dust/glue patch stands out.

Mike

[Ed Aumiller]

If you are not staining it.... I put a smidgen of super glue in the crack then immediately rub superfine sawdust on it...
If using stain, rub superfine sawdust on it while the stain is still wet... the stain will normally hold it until the final finish is applied..

[Steve Demuth]

I’d caution the glue/dust method. Every time I’ve tried it, it sticks out like a soar thumb after finish is applied. I suggest inserting thin shavings if possible, or using wood filler like Timber Mate or Famowood.

Yes, with one exception: it works well when filling alongside endgrain - such as along dovetails and box joints. The glue is not the primary problem with stains and finishes on these repairs, it's the fact that the exposed sawdust drinks the stain or finish just like ... endgrain.

[Bruce Page]

I’d caution the glue/dust method. Every time I’ve tried it, it sticks out like a soar thumb after finish is applied. I suggest inserting thin shavings if possible, or using wood filler like Timber Mate or Famowood.

I haven't decided on the finish but will probably do a solid color like ebony. Small wood slivers would be ideal but in this case the gaps were too small for that approach. If I'd paid a little more attention during the glue up we wouldn't be having this conversation. :rolleyes:

[Brian Behrens]

I've been unhappy with glue/sawdust on cherry finger joint boxes. It depends on the size of the gap you are trying to fill. In my case I switched to using 2 part epoxy, without sawdust mixed in. I found it to be invisible once my lacquer was applied.

[Tim Janssen]

Anytime I have tried to use a mixture of glue and sawdust it has always turned out quite a bit darker than the wood itself. So I have given up on that.

Tim

[John Redford]

Try clear shellac and sawdust.

[Sam Puhalovich]

Like others, I tried the glue-and-sawdust mix ... it came out darker ... and it was problematic to get into some voids.
This is what works for me: apply thinned glue (from the brush-soak jar) to the gap ... run-over the gap with the ROS.
I get a perfect 'fill' with no change in color.

[glenn bradley]

Try clear shellac and sawdust.

Ding, ding, ding; this is how I handle this problem. Sanding with an oil based finish to create a slurry is also a good method for me.

[Bradley Gray]

if the gaps are too small for slivers of wood I wait until I have 2 coats of varnish and then fill with clear epoxy, no dust.

[Charlie Jones]

I use this method sometimes for slight gaps in darker woods. I sand a pile of dust with 80 grit, dip my finger in a little glue then in the dust. Rub it in. Then rub in more dust. Works good if using an oil finish. May not be good for high gloss.

[Bruce Page]

I mixed up a paste and happy with the results. There's more to do before I put the finish on.