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Anthony Scott
03-25-2021, 4:12 PM
So came out to the shop today to find an enormous crack in the slab I just bought.
I’ve seen others use butterfly keys and epoxy to fix cracks but not this big of a crack.
I’ve never done butterflies so I am unsure of my ability to do that.
what are the thoughts on wether this is salvageable or not? Thanks.
pic should be attached.

Andrew Seemann
03-25-2021, 4:28 PM
That is a pretty straight crack, and the grain looks like it is going to have a permanent attitude problem, does your design allow for ripping the board and gluing it back together sans crack? You might want to wait for the wood to finish drying first before you do that though.

Patrick Kane
03-25-2021, 4:33 PM
Your explanation makes it seem like you purchased this slab without the check, and that the check seemingly happened overnight. If that is the case, you have some serious moisture/drying activity going on in your shop.

Whats the intended use for the slab? Table top or similar? If it needs to remain in one piece, you can try butterflies or epoxying the void. I am pretty concerned that the check seems to run 80% of the length of the board. Its enough that i think i would forgo the other options and rip it down the middle, joint the edges and glue it back up. What does the end grain look like? Im almost convinced that the pith was included in your board, which lead to this monumental check. If that is the case, theres almost no fixing it with butterflies, epoxy, or anything else.

Dean Egnater
03-25-2021, 5:02 PM
I used epoxy to fix a very punky slab a while back...you can search my name and see pictures. If pith is the reason it checked you can use total boat penetrating epoxy to harden the pith and then fill with epoxy if that is the look you are going for.

Anthony Scott
03-25-2021, 5:34 PM
This is going to be a desk top. The ends look pretty solid. This slab was about 2 feet longer and a check was cut out of it.
I can see a hairline crack extending past the visible crack. But I can’t flex the two pieces on either side of the crack.

Bill Dufour
03-25-2021, 6:51 PM
wood type, your location or climate. I would let it dry then rip it in two and reglue.
Bill D

Bryan Lisowski
03-25-2021, 8:13 PM
I would fill with epoxy with a black tint. Just may need to do multiple pours.

John TenEyck
03-25-2021, 9:08 PM
Buying green or partially air dried lumber can often lead to heartache. Bringing it inside before it's fully air dried almost always will.

John

Bill Dufour
03-25-2021, 9:38 PM
I am surprised it cracked so so quickly. I thought Scotland had a damp climate? Scotch Pine by chance?
Bill D.

johnny means
03-25-2021, 9:59 PM
No it's not salvageable. It's kindling now. I'll stop by with my van to take it off your hands.

Mark Gibney
03-26-2021, 12:43 AM
Two ways to deal with this.
One is to separate the two halves but you can't cut a straight line or you'll lose a lot of wood when you joint the sides for re-gluing back together.
I would draw a line that is a continuation of the long check as a fair curve and cut it with a jigsaw.
Then I would make a template from 1/4" material that follows the line of one of the halves. Use the template and a router to "joint" the piece.
Then use this freshly jointed curved edge to router "joint" a mirror profile on the other piece.
If you want to use avoid all that and instead fill the check, reinforced with butterfly keys, you can put them on the underside and nobody will see them, if you're concerned about your yet-to-be-developed skills at this.
And they don't have to be butterflies, they can be simply rectangular lengths of lumber. Our modern glues do the work.
Then to fill a crack that big I would use SculpWood paste that I colored with Transtint dye or with powered color. It's a lot easier to use than regular epoxy and sands much easier.

Stan Calow
03-26-2021, 10:00 AM
I am not a fan of butterflies. I think woodworkers like them because they think its a cool trick, but to others, it looks like a bandaid. With all that nice straight grain, I'd do what Mark suggests, and rout it down the crack.

Alex Zeller
03-26-2021, 12:13 PM
I think I would talk to the seller. Since it already had a check I would say, unless you did something really wrong, it's most likely a problem with the wood itself. Possibly the slab was cut too close to the pith? It could have been the part of the slab keeping the check from going further was also cut off when the check was removed. Cutting and gluing it together would work but you paid for a nice wide slab not two smaller boards to be glued together. Hopefully they are willing to work with you and come up with a compromise.

Stephen Bandirola
03-26-2021, 12:29 PM
Two ways to deal with this.

I would draw a line that is a continuation of the long check as a fair curve and cut it with a jigsaw.
Then I would make a template from 1/4" material that follows the line of one of the halves. Use the template and a router to "joint" the piece.
Then use this freshly jointed curved edge to router "joint" a mirror profile on the other piece.
r.

Are there any instructional videos of this technique?

Patrick Varley
03-26-2021, 4:22 PM
Are there any instructional videos of this technique?

Stumpy Nubs: Complimentary Curves (https://youtu.be/fZmIMmdCTYA)

Obviously this is a larger scale, but principle holds.

Anthony Scott
03-26-2021, 5:42 PM
I would fill with epoxy with a black tint. Just may need to do multiple pours.
How long to do you let one pour dry before doing the next?

Mark Gibney
03-26-2021, 5:45 PM
Good video. Stumpy Nubs is great!

Anthony Scott
03-26-2021, 5:46 PM
Regarding cutting and glueing back together, I’m thinking no matter how I do it I’m going to get a noticeable seam. And of course I won’t know until it’s done. True?

Andrew Seemann
03-26-2021, 6:14 PM
You will notice the seam if you look for it. With it being down the center of the slab, it likely will not be very noticeable in use though.

lowell holmes
03-26-2021, 8:00 PM
I would rip it on my table saw and glue it together with dowel pins 12" on center.

Stan Calow
03-27-2021, 10:09 AM
Regarding cutting and glueing back together, I’m thinking no matter how I do it I’m going to get a noticeable seam. And of course I won’t know until it’s done. True?
Thats the advantage of using a router to cut following the crack - a curvy line catches your eye less than a straight line.

Tom Bender
04-05-2021, 7:00 AM
An epoxy fill will be really annoying on a writing surface. But then very little writing happens anymore.

Cary Falk
04-05-2021, 6:09 PM
I would joint along the crack using a router as suggested and reinforce with biscuits.