I recently attempted to glue-up walnut slabs (boards) to make a table top. Festool dominos were used to join the 2″ thick boards. The glue up resulted in small (<1/64″) cracks along some of the boards that extend almost the entire length of the board(s). What is the best way to correct this? By re-sawing along the cracks/seam? By colored epoxy filler? Other?
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If you can bear to lose the width then definitely re-saw and glue again.
Those are nice boards and I think any epoxy will show terribly.
100% agree!
Ok, in answer to multiple posts, I did not cut the boards as my track saw only cuts to 2” thick and the boards were originally 2.25 inches thick. The boards were also joined with dominos by same party. Irregardless, I have the problem. I used Titebond 3 as the glue. The boards came together nicely (no cracks in pre glue check.). I can only assume the glue dried too quickly on the dominos and prevented the boards joining seamlessly)
If I resaw do I need to saw down the center line of the cracks or on both sides of crack ( which may mean more issues in tealign.)?
Saw down the center of the crack, then rejoint the parts. If you domino again do NOT glue the dominos, they are only needed for alignment.
Why do you say don't use glue on the dominoes? I would agree if you were talking about biscuits, but dominoes actually add strength to the joint. In general, glue is more than enough for edge-to-edge gluing, but why not add a little extra insurance?
What did the dry fit look like? How did you get the edges square? Did you glue up all boards at once? What glue? I just had problems with a much simpler glue up than yours, edge grain cutting board. Edge clamps held, center one sprung, gaps in the center. Everything looked good initially, nice glue squeeze out, problems after everything was done and I applied mineral oil. I could cut thru the bad joints and reglue. When I lined up the sections, I saw no problems in a dry clamp. The good thing about my project was the wood was not expensive, used a lot of glue, but this is a hobby for me so time expended is not a issue. Good luck.
For a strong glue joint assuming you use PVA glue you need flat straight and square edges and a lot of clamping pressure, the joint then is stronger than the wood. Need to rip through the joint and start again. What do you think went wrong with the glue up ?
What is the white piece under between each board ?
The white piece is my Festool HEPA vacuum. 2x4s are supporting the table top which are supported by Kreg sawhorses.
The white thing that is inserted in a rabbet between each board .
Is it possible that the mortise is not quite deep enough and the domino is bottoming out in it before the boards are pulled together? Could be trash or sawdust in the mortise also.
I’ve never used a Domino but doesn’t it automatically size and clear the mortise?
I have never used one either but had a similar problem with biscuits once....operator error I hate to admit. And "automatic" does not always work. I would see nothing wrong with cutting a sixteenth or so off the domino for extra insurance. Also, too much glue in the bottom of the mortise can keep the domino from seating fully.
According to post #6 a third party cut and dominoed the table so he wouldn’t know the method used to square the ends of the boards or how the clamps were used.
It’s interesting that the 2X4s with the white tabs, supposedly supporting the table, have the same grain pattern as the table itself.
Although the white tabs? appear to get progressively thinner, they look like they are inset into the bottom of the table. Possibly running the full length? If so, being a different species, they may have absorbed more moisture from the glue and expanded more than the walnut and prevented the edges from adhering properly. That may have made what looked like a good glue up with clamps on start opening when the pressure was taken off.
I'm reading the white tabs as some kind of tape.
Me too. I assumed they were there because the OP considered filling the cracks with epoxy, hence the tape at the bottom.