Question about wood movement

[Joseph O'Leary]

I am in the process of final sanding and preparing to glue up the foot boards for a set of bunk beds. My question is if there may be a problem with gluing the dolphins together where they cross each other. Everything is tight and sturdy but I would keep little boys from sticking stuff between the dolphins and doing damage. My thought is that the grain is all parallel, all four dolphins are from two pieces of adjacent wood cut from the same tree so they should all grow and shrink together.:rolleyes: I may be too optimistic. Any input would be greatly appreciated.

[Fred Voorhees]

Joseph, first things first. Nice job on those! Is that walnut? To answer your question, in my opinion, I wouldn't want to glue them together.

[Robert Waddell]

Joe,
If they are walnut then they won't move much and with the grain direction matching, I don't think there's a problem. I agree that kids will try anything and not only tear-up everything but will find a way to get hurt by getting stuck between these two pieces. I'd fasten them together somehow.
Rob

[Greg Funk]

Joseph,

When making large doors it's not uncommon to laminate two 1"+ thick boards together to make the rails and stiles. These laminated boards tend to be more stable than solid stock so I can't see that wood movement would be an issue if you glued the Dolphins together.

Nice bed by the way.

Greg

[Jamie Buxton]

That's a way cool design!

How is it a bunk bed? I'm not seeing any way to stack a bed on top of the other one.

There's no issue at all in gluing the two dolphins together. As you say, the grain direction on the two is the same, so they'll move in the same way.

If there's any hazard, it is in gluing the dolphin noses into the bed posts. In theory at least, the dolphins will grow and shrink in height, but the posts will not. You might get away with it -- the dolphin beaks will flex just a bit. But if you were really concerned, you'd let the noses slide up and down in the mortise in the post.

[Joseph O'Leary]

Thanks for the advice and kind words. The wood is air dried walnut. These are the short foot boards for the bunk beds. I still have to make the tall head boards. From the top of the "spout" down to the first bead is a finial (sp?) that will be drilled to accept a dowel to go into a matching hole in the top of the corner post. When the beds are bunked the shorts go on top and the talls are on the bottom. When unbunked one tall is at the head and one short is at the foot.

[Jamie Buxton]

From the top of the "spout" down to the first bead is a finial (sp?) that will be drilled to accept a dowel to go into a matching hole in the top of the corner post. When the beds are bunked the shorts go on top and the talls are on the bottom. When unbunked one tall is at the head and one short is at the foot.

That's a clever solution!

[Jim Becker]

Joseph, those are GREAT!

And I concur that there would be no problem with gluing the pieces in question...they completely match up for grain direction, etc.

[John Fry]

Hmmmm!

At first, I quickly thought that the "dolphin's" grain run together and there should be no problem. Then after further review, I don't think I would glue them together.

The potential problem is the overall tendance for the dolpin's grain to move vertically and force the "nose" to move up or down "fighting" with the cross grain joint created at the post.

By not gluing, there might be enough movement absorbtion in the "arched" design of each individual dolhin body to prevent a problem. But glue them together and they must expand/contract together and that means straight up and down only. I think that could cause problems where the nose is mortised(?) into the post.

I vote no glue and if really necessary, screw them together from the back with elongated holes or through slots.

My 2 cents.

PS. congrats, on a very neat design, I really like it