Panel Construction Question

[JohnM Martin]

Admittedly, this is probably a very elementary question, but I've searched the web and haven't found a lot of great answers so far so I thought I would ask it here. I'm relatively new to woodworking so I apologize in advance if this a dumb question...

When constructing panels (e.g., for a bed headboard) when is it appropriate to a use tongue and groove and when is it appropriate to use just an edge glue up (with or without biscuits for alignment)?

Thanks in advance.

[John TenEyck]

I can't think of a case where tongue and groove would be needed for a glued up panel. Edge glued is just fine, maybe the strongest, too. As you said, you can use biscuits, Dominos, dreaded (in my world) dowels, etc. for alignment if you like, but nothing is required from a structural standpoint.

I would reserve a tongue and groove joint, or spline and grooves, for an unglued panel.

John

[Keith Hankins]

First no such thing as a dumb question. I'm going to dive in a little deeper. For a headboard in your example if the grain will run lateral i.e left to right, you Just glue it up.

Where it gets tricky is when you run into a cross grain glue up. For example lets say you want to run those boards vertical with a boarder all the way around, and the width (remember expansion is across growth rings), then Tongue n grove could be a decent solution In the link below is an example where I had some vertical boards bound by a frame in a hutch. I had to allow for movement so tongue-n-grove will work great.

https://flic.kr/p/dRBAPM

Now if it's like the first one I spoke of (lateral grain), then just glue the boards together. Now its critical to allow for movement where you have a wide solid panel and its connection to vertical running grain like a bed post.

In this bed I minimized my contact by narrowing the points in contact, and two, I made the mortise wider than the points so it could float. I also did that for dissasembly of the bed rails and headboard for moving later.

https://www.flickr.com/gp/22447246@N06/0RGvPi

Hope that helps and good luck just remember where grains cross they got to be able to move a bit laterally across the growth rings. Cheers!