Need to repair a crack

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berry
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Need to repair a crack

Post by berry »

I'm making an end table from oak (5/4 red oak). One of the pieces I'm working with has a serious check at one end of the board. This un-milled stock that's been in my shed for 3 years. At the end of the board it's about 3-4 inches from an edge. It's about 15" long and runs almost to the edge.

Should I break it off and glue it back on? Or get a syringe, fill it with glue. Pry open the crack and shoot the glue in and then clamp? I know if I break it off I'll be able to get glue covering both surfaces fully BUT getting a part that's broken off to fit perfectly again can be an issue. I use Titebond PVA or Titebond pre-made hide glue, both pretty thick and trying to for it through a syringe to cover all the surface???

Thanks for reading.
crack 41.jpg
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RFGuy
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Re: Need to repair a crack

Post by RFGuy »

Safest option is to remove that checked end and not use it, but this isn't always possible. How I have handled this on a board where I couldn't sacrifice the length is to drill holes across grain and insert dowels through the sides. This works best when you can hide this, e.g. facing the back and/or make it an interior board in a panel, etc. Depending on how much stress is still in the lumber, sometimes you can try to force glue into the crack and it works if there isn't too much trapped tension. If you do, one tip is to use a shop vacuum to suck from the bottom of the board to pull the glue through the crack from the top.
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JPG
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Re: Need to repair a crack

Post by JPG »

I would TRY thin super glue. Working time will be a problem. Does it pull tight easily when squeezed back together?

Start at the closed end, spread and glue a short distance, clamp, allow to set, then spread and do the next short distance progressing towards the open end. Finally allow glue to seep into the entire crack.(both faces)
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BuckeyeDennis
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Re: Need to repair a crack

Post by BuckeyeDennis »

Ditto JPG’s question: If you put a clamp or two across the split, does it close up nice and tight? If so, I think you can make an almost invisible repair.

I’ve had excellent success with the thin, slow-cure System Three epoxy that Woodcraft sells. It wicks right into both punky wood and cracks. If you look closely at my finished Walnut bowl in this thread, you can see a number of small splits resulting from my accelerated dessicant-drying experiment. They’re just a bit darker than the wood. While rough-turned, I taped off the cracks on the bottom of the bowl, applied the epoxy on the inside, and it wicked all the way through. I had to keep adding more as it wicked in. And being epoxy, it filled the cracks with no shrinkage.

If it takes a LOT of clamping pressure to close up the crack, then RFGuy’s suggestion to reinforce with dowels might be a good idea. But if the checking is just from uneven end-grain drying, and the board is now nice and dry, then the internal stress should be pretty much gone.
FalakCobb
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Re: Need to repair a crack

Post by FalakCobb »

Apply superglue or wood-filler epoxy resin to small broken bits and gaps. Superglue or wood-filler epoxy resin are both great options for repairing wood furniture that has slight cracks, small breaks, or pieces that have fallen off. These materials work to securely bond the wood pieces together.
Hobbyman2
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Re: Need to repair a crack

Post by Hobbyman2 »

I have made repairs to cracked gun stocks using dowels 2 part epoxy and clamping . the biggest thing it to make sure you work the adhesive completely into the cracks and making sure the end of the crack has plenty of glue or the crack can come back . just clamp it, drill the holes for the dowels, than unclamp it, add the glue , re clamp it , tap in the dowels and allow to dry . JMO
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Erik
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Re: Need to repair a crack

Post by Erik »

I'm not sure if it would work here, but I've repaired narrow cracks that were more parallel to the edge of the board by simply ripping the board through the center of the crack and then gluing up the new edges. What I like about the ripping method is that the glue line is practically invisible because you are putting the board back together again. In the couple of times I have used this approach I did deploy my taper jig to get the crack exactly lined up with the kerf of the saw blade. This crack appears to be across the board so the ripping approach might not work as well since your "rip" cut would exit the side of the board.

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everettdavis
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Re: Need to repair a crack

Post by everettdavis »

If you use the super glue method gets CA glue that requires an activation spray.

You would need to set up your Clamps and use wax paper to protect clamps. Insert the glue, clamps it moderately, then spray on your activator while it is gently tensioned.

Let it cure, and gently release pressure

Use a scraper to clean surface of glue ridges.

To prove up your technique find another piece of cracked scrap to simulate your fix, and test the resulting repairs before doing your working piece.

Everett
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everettdavis
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Re: Need to repair a crack

Post by everettdavis »

everettdavis wrote: Mon Feb 08, 2021 3:37 am If you use the super glue method get CA glue that requires an activation spray.

You would need to set up your Clamps and use wax paper to protect clamps. Insert the glue, clamps it moderately, then spray on your activator while it is gently tensioned.

Let it cure, and gently release pressure

Use a scraper to clean surface of glue ridges.

To prove up your technique find another piece of cracked scrap to simulate your fix, and test the resulting repairs before doing your working piece.

Everett
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