Panel glue up

[Brian Runau]

I have a 36" X 48" panel glue up coming up. Would biscuits or domino tenons help keep the joint height more even and keep it flat? Thanks

[Greg Quenneville]

I think that dominos have less wiggle room than biscuits but my biscuit joiner is a pretty “budget” type brand.

[Mel Fulks]

Sure, some don’t like biscuits. But you just tell them, “well , don’t eat them”. Splines have been around a long time …what’s the difference?

[Steve Jenkins]

If you alternate the clamps top and bottom you can flatten the panel.

[Mel Fulks]

One thing that helps flatness is lay out the boards in the order you want , then joint one board “in”next board “out” . That way any slight
deviation off 90 degrees,of the fence is canceled out. And I use spring clamps on the ends to keep the pieces from moving . And if you
learn to make “sprung” joints you won’t have any panels popping open at the ends.

[Jim Becker]

It's common to use Dominos, biscuits, dowels, splines, etc., to help with panel glue-ups and keeping one face perfectly in-plane across the assembly. The single requirement here, other than a tool that provides the mortises/grooves/holes/whatever doing it in a way that's not too sloppy, is making sure you indext everything off just the top surface...the one you want to be in-plane.

You can also do these glue-ups without embedding things in them by other methods as folks have mentioned, including using cauls, especially those with a slight bow that forces things flat from the center out.

[Michael Burnside]

One thing that helps flatness is lay out the boards in the order you want , then joint one board “in”next board “out” . That way any slight
deviation off 90 degrees,of the fence is canceled out. And I use spring clamps on the ends to keep the pieces from moving . And if you
learn to make “sprung” joints you won’t have any panels popping open at the ends.

This is great advice. I always do this either in/out of jointer or up/down on the table saw. OP I would use dominoes for a gulp up that big and use advise here as well.

[Brian Runau]

One thing that helps flatness is lay out the boards in the order you want , then joint one board “in”next board “out” . That way any slight
deviation off 90 degrees,of the fence is canceled out. And I use spring clamps on the ends to keep the pieces from moving . And if you
learn to make “sprung” joints you won’t have any panels popping open at the ends.

Thanks Mel, great suggestion. Brian

[Alan Lightstone]

I tend to use dominos and cauls, but I'm a belt and suspenders kind of guy.

Dominos will work fine. Just take care indexing all of them correctly.

[Bryan Hall]

Yep, agree with Mel and Jim. Jointer for getting the panel to come out flat. Biscuits and dominoes yield the same result for me when it comes to having a flush joint. I’ve used cauls as well.

That’s big enough that you should be able to dry clamp it and see quickly if it has a serious tendency to bow or not.

[Mark Rainey]

I like Veritas panel clamps herehttps://www.leevalley.com/en-us/shop/tools/hand-tools/clamps/31181-veritas-panel-clamp?item=05G1601

[Curt Harms]

I've used biscuits, I haven't used dominoes. One of the complaints about biscuits is that the wood on either side of the slot is prone to swelling due to moisture from glue inserted into the slot. If you then sand the piece while the wood is damp from the glue, when the glue dries there'll be a slight depression. Don't dominoes have the same issue? Or is there less glue used with dominoes?

[Brian Runau]

Thinking to add 3 dominoes per joint. I have 6 joints. I made a set of three cauls and will alternate clamps top/bottom. Would you do this in one glue up or do two and the join them?

[Thomas McCurnin]

I have used biscuits, but alignment has to be 100% perfect, as there is none, zero play up and down, and unless you provide some decent and consistent pressure to the biscuit joiner's fence to insure that each side of the slot is exactly the same, there might be an alignment problem. Add a dozen or more slots, and the risk of misalignment increases exponentially. Therefore I use cawls and weights to insure the panels are in alignment before I tighten the clamps, while I am tightening them and afterwards before I walk away. I'll often go back in a few minutes and check alignment and wipe off squeeze out, and if necessary, re-clamp the panels.

[Jim Becker]

Thinking to add 3 dominoes per joint. I have 6 joints. I made a set of three cauls and will alternate clamps top/bottom. Would you do this in one glue up or do two and the join them?

That can be reasonable, but is always dependent on the total width of the panel for "best effect". Only the middle mortise should be "tight" laterally...the others can use the loser/wider setting which will make your glue-up a lot easier. As long as all of the mortises are indexed off the same surface of the boards (presumably the top, "best", surface) you'll get the intended result. The same holds true for biscuits, dowels, splines, etc.

[Alan Lightstone]

I've had great success with the Woodpeckers clamps (not the Clampzillas. Still trying to figure out how to use those. Too bizarre) and dominos.

The Woodpeckers clamps I have aren't wide enough for your top, though. My cauls are. Not sure what they call them. They are essentially big honkin' aluminum square tubes with screw down clamps on the ends. Their version of metal cauls. They work quite well if your panels are truly all the same thickness.

Jim's advice about tight vs wider setting on the domino is quite important. Otherwise, screaming and cursing can result when you realize that the panels don't perfectly line up laterally.

[James Jayko]

If you do use biscuits, I think you want to cheat them away from the show face of the panel. I'm not sure the reason, but if biscuits are too close to the surface, they can 100% telegraph where they are.

[Brian Runau]

That can be reasonable, but is always dependent on the total width of the panel for "best effect". Only the middle mortise should be "tight" laterally...the others can use the loser/wider setting which will make your glue-up a lot easier. As long as all of the mortises are indexed off the same surface of the boards (presumably the top, "best", surface) you'll get the intended result. The same holds true for biscuits, dowels, splines, etc.

Jim, here's the dry fit. Worthless cauls I built, oh well, live and learn! Might work on shorter distances? Just bow in the middle at 1-1/2" thick in the poplar. 3 dominos, 1 center and 6" in from each end. Center was std width and ends we next setting up on the domino. Pretty flat, still some unevenness at some of the joints. but I think this should sand out OK and leave me with a reasonable flat panel. I will use more clamps from the top during the actual glue up. thanks brian

493116

[glenn bradley]

Looks like you've got it Brian so I am late to the party. For large panels I use splines to provide a continuous run of "support". If I am using beard board ends I run them full length. If not, I use stopped grooves. Always more than one way to skin the cat.

[Brian Runau]

Looks like you've got it Brian so I am late to the party. For large panels I use splines to provide a continuous run of "support". If I am using beard board ends I run them full length. If not, I use stopped grooves. Always more than one way to skin the cat.

So you create a tongue and groove? thanks brian

[Michael Drew]

That's a good sized glue up. I'd probably do it in stages. Maybe glue up three sections, then join those? I'm limited to what I can flatten with my sander (or planer), so I usually plan to do this and mill the boards a touch wider than my target finished width.

I used to rely on biscuits and/or dominos to "assist" with alignment, but jeezus.....the extra time fiddling with them and the glue would create too much anxiety and I would inevitably, end up screwing the thing up. I no longer use them. I now use 3" PVC pipe to help with panel glue ups. I have three separate, 32" lengths of PVC mounted to some wood bases. I can clamp the wood bases to my bench. The PVC is flat, straight, pretty strong, and glue doesn't stick to it. I can clamp a caul to them, sandwiching the boards between the PVC and cauls. I built the cauls from laminating BB ply (1.5" wide), then ran them over the jointer to get them straight. I used some self adhesive teflon to keep the glue from sticking.

[Jim Becker]

So you create a tongue and groove? thanks brian

It's similar, but a spline is a "loose" tongue/tenon that's long and fits snuggly in a groove across all or most of the panel, depending on whether or not you want it to be visible or not at the edge. Consider a spline a really long biscuit. :) :D