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Discussion Starter #1
I've made a hardwood table out of Blackbutt. I used biscuit joins to join the top of it. I had it finished perfectly with no gaps but because I was working on it in our garage, the heat caused a bit of expansion and now there's a slight 2mm gap between 2 of the pieces.
I want to finish it with an oil but I am hoping to fix the join beforehand. I originally joined it with sash clamps but they're not going to be strong enough to fix it now.
I've considered PVA mixed with saw dust but I fear that it will stand out when the finish is applied.
Any recommendations would be great!
Thanks
 

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Saw down the glue line and re glue. I wouldn't use biscuits. :smile:
+1 on ripping and re-gluing - without biscuits. The heat did not cause expansion, but may have caused the wood to loose some moisture and the gap is due to shrinking.

Biscuits do not add to the strength of the joint. If you need to control alignment, I would use a dowel at one end and cauls along the length to keep the top aligned and flat.

http://www.woodworkingtalk.com/f2/teach-me-about-wood-cauls-please-44702/
 

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You are right about the sawdust and PVA showing, it will stick out like a sore thumb. I'm another who would resaw right through the joint and then reglue.
 

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Discussion Starter #5
Thanks for replying so fast.
As you can see by these photos sawing and re gluing isnt really possible. Any other suggestions?
 

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Yeah, if it's permanently fastened to the Apron, this is just the start. Typically the top will be fastened with screws in elongated holes, or figure 8's, or one of several methods that allows it to move yet stay secure to the frame. At this point, the only repair option may be to cut a small section out (somehow) where the split is, and carefully fit a replacement piece of wood in there. I'm not sure doing that is going to gain you anything, since I'm pretty sure you'll see more splits over time.
 

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In History is the Future
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Leave is as is. It's going to continue moving - shrinking and expanding with the seasons and it's going to continue to get worse for a couple years.

If you try to spot fix it - the repairs will then split and you'll be repairing repairs.

Best to walk away and write it off as a learning experience and do better next time.

The only viable option (that I see) is to run a shallow V at all of the joint lines to hide the split and make it appear as it is an intended design feature. The only problem with that option, though is that, assuming the other seams were not glue starved or some other issue, new cracks will not be on the glue seams.
 

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Old School
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Here's what I would do. I would take the top off, and cut the joints, and re-glue and clamp. No biscuits or splines.

I would attach a cleat on the side to side stretcher/support 90° to it. In that I would make elongated slots. A fixing screw can be used on the center board, and washer head screws, or pan heads with washers used in the slotted holes away from the center. I wouldn't use the apron.






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Mike, how would you go about removing the top?
If it's glued to the apron, using a heat gun along the glue line, will usually release the bond (depending on the glue used). I could also give it a reason to come loose with a chisel and a mallet from the inside.

At least trying the modification to the top may give it some predictability.






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Does anybody have a link that talks about the different ways to safely join your table top to your frame to make up for any expansion ?
 

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Just curious - I know biscuits aren't favored by many posters on here - but are you guys attributing the gap that occurred to the use of biscuits? I've used them in a number of edge joining projects and never had a joint open up.
 

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Just curious - I know biscuits aren't favored by many posters on here - but are you guys attributing the gap that occurred to the use of biscuits? I've used them in a number of edge joining projects and never had a joint open up.
Dowels can do the same thing. As the wood expands and contracts the dowels act like little jacks and push the joint open. However in this case it's probably the apron causing the problem.

If you don't want to remove the top you will have to run a saw down the middle of each glue line and separate each piece from the other. Otherwise the problem will continue or even get worse.

I've tried but it is very hard to convince wood not to move across the grain, you have to plan for it.

Bret
 

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I've tried but it is very hard to convince wood not to move across the grain, you have to plan for it.

Bret
This is true! Blew my mind the first time I saw old pinned top tables - where the top is pinned down with wooden dowel into the aprons. It works though - I've built em and never had an issue. The dowels must allow just enough movement to make it work.

Jean
 
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