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View Full Version : End grain joint in panel glue up



Myles Moran
01-28-2024, 8:18 PM
Long story short, I bought a bunch of 8/4 poplar for an aquarium stand a while back. I cut it into appropriate length pieces for that project so I could get it into my shop and start acclimating it.

Fast forward to now, and I'm about ready to start on that project. So I started laying out the design, scaling it for the room, and after a bunch of hemming and hawing, my wife and I both agreed we don't like that idea. So now the plan is a console for below the tv. The aquarium stand was going to be around 4' wide. The wood was cut to 4.5-5.5' long (mix of lengths to get 2 legs from the longer pieces or one 4' cross piece from the shorter pieces). The planned console table is looking like it'll be 6.5' long.

I'd like to use this wood if possible, I'm semi-limited on storage space and I don't use much poplar. I'll have a lot of resawing to do, but that's not the end of the world. The biggest issue is going to be getting a 6.5' long glue up for the top. Given I'm going to paint this, is there any reason I couldn't make a tongue and groove joint (or use the excuse to buy a glue joint router bit) to turn a 4' piece and a 2.5' piece into a 6.5'' board for a panel glue up? Or am I going to have to admit defeat and get the proper material from the sawmill?

Lee Schierer
01-28-2024, 9:09 PM
It would really help to have a sketch of the stand you are planning to give an answer.

Cameron Wood
01-28-2024, 10:03 PM
I had a situation like that where there needed to be a joint because the stock was not long enough, & ended up with two butt joints with something like 2/7:3/7:2/7 proportion.

Jamie Buxton
01-28-2024, 10:28 PM
You could make boards which are 4'+2.5', and when you glue the boards into a top arrange them so that each 4'+2.5' board is flanked by a 2.5'+4' board. That is, an endgrain joint in one board is flanked by solid lumber on both sides. It'll be completely solid.

Cary Falk
01-28-2024, 11:09 PM
If it is going to be painted I don't see why not. I would use a finger joint bit and alternate the short cut ends as mentioned before.

Kevin Jenness
01-29-2024, 6:28 AM
There's always a potential for butt- or finger-jointed pieces to flash under paint. The panel will be sound enough if you stagger the joints. Personally I would buy some more boards if the panel is going to be highly visible. Poplar is inexpensive- how much is your time worth?

Ron Citerone
01-29-2024, 7:56 AM
There's always a potential for butt- or finger-jointed pieces to flash under paint. The panel will be sound enough if you stagger the joints. Personally I would buy some more boards if the panel is going to be highly visible. Poplar is inexpensive- how much is your time worth?

I agree with Kevin. In the long run you will be happier and probably if you stare at that Poplar long enough you will find a good use for it. Win win.

My 2 cents.

George Yetka
01-29-2024, 9:46 AM
If you frame it like this I would think your material would go. You may need more though. Esentially frame the center cube. Then attach to either side.

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Jimmy Harris
01-29-2024, 10:15 AM
Stagger the joints and you should be fine. You could use tongue and groove, box joints, or finger joints to avoid the butt joints, but I don't think it would be a necessary step.

A trick I've found to getting a strong butt joint in end grain is to plane the ends with a hand plane on a shooting board so they're absolutely smooth. Then mix up about a 50/50 mix of water and PVA glue and spread that over the butt joints. Let it sit for a few minutes until it completely absorbs into the end grain. Then glue it up like normal with 100% PVA glue. By planing the end grain, you get a smoother surface, better fitment, and more glue surface than if you glue it fresh off the cut. And you slice open the fibers which seems to help them absorb glue better than sanding smooth. The 50/50 mix draws the glue deeper into the wood than wood glue alone, and provides a backstop for the 100% glue you add later, so the porous nature of the end grain doesn't starve the glue joint. It's still nowhere near as strong as a finger joint or whatever where you'd have long grain to long grain, but it's a lot stronger than a normal butt joint in end grain.

Myles Moran
01-29-2024, 10:19 AM
Lee, here is the sketch I have so far. I'm thinking mortise and tenon rails top and bottom with panels on the sides and back, and doors on the front. The doors will hide pull out drawers for storage (we have a nice home for the AV equipment already). The top itself is right around 6.5' wide.
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Jamie, that would be my intent to stagger the end joints sort of like a brick pattern.

Kevin, I agree there is a chance and I think the end joints showing up would be worse than the side grain joints showing up. I've never considered a joint like this before since I typically don't build anything painted and the grain pattern would look weird.