desktop seam support question

My personal preference is to use dowels. - which I guess, is really a form of floating tenon.

diggerop

I'd probably go w/ a groove/spline (essentially the tenon except probably 3/4's the length of the edges. And, I'd add a ledge underneath (as an add-on moulding, most likely) so it'll take somebody getting up there to hang a picture in the corner, etc.

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The design includes a back leg and arched brace, hopefully that will be enough. The top is 1" thick solid hardwood (one's oak, the other desks are maple).

How about: Biscuits or dowels with no glue. 1" angle iron along the seams. If you ever need to move it, it can be easily disassembled.

Sonny

I wasn't going to glue it anyway, hence the draw bolts.

Angle iron?

Just need to have enough beef in the support to handle the unexpected--somebody, sometime _will_ look at that hunk of oak and say "I don't need no steenkin' ladder to change this-there blulb in that-there light!" or somesuch...

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That someobody will probably be me, too.

DJ,

I built some "L" shaped craft benches a couple of years back that I aligned the two sections using two #20 biscuits on each seam. No glue, assembled them dry so when / if they have to take things apart, they can. I used two 1/2" diameter draw bolts on each seam to hold things together. These benches have taken a beating and the seams haven't budged.

Other ideas will certainly work but "simple" usually works better than some "over-engineered" ideas.

Bob S.

The question to ask is "would I screw my wife on this?". If not then it's not strong enough.

My first thought is your going to get quite a bit of expansion and contraction with that wide of a hardwood top and I would want to have a web frame under the center section as well as the sides that provides support and a way to connect that allows the top move; otherwise you risk it cracking on you. You have the back side covered but appears nothing to tie to in the front. Either a divider in the front or a complete top web frame would be the direction I would head in.. I would also incorporate some cross members into the web frame for attaching the keyboard tray.

Idea... it occurs to me I could make the seam with rabbets to create a narrow lap joint, say 1/4 deep or so. Then the center section would be resting *on* the side sections, sort of.

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How about some angle iron, maybe 3/4" in size? It could start a few inches back so it's not noticeable.

It occurred to me that the front intersection isn't straight, so this type of seam would be messed up there :-(

Probably too low tech for you but I'd just add a board under the side modules that extends, say, 3/4" past the top. The corner module would then sit on those and be held to the side modules with the draw bolts (which might need a smidge of updown wobble). Alternatively, a couple of threaded inserts along the underside of each side of the center module, bolts through the added boards into them; taper the center module edges slightly downward for easy bolt insertion and a "just grew there" look when snugged up.

That would add a new problem in as much as ends of the boards would be visible. Two solutions...

1. Make them maybe only 2/3 - 3/4 as long as the side modules are wide. Not totally invisible but unless someone is crawling around on the floor they wouldn't be seen.
2. Put a keyboard tray or drawer under the center module. This would get my vote.

Why would it be messed up?

Where the two sections meet is an inside corner. Any non-flat edge would have to be coped into the other section.

I must be missing someting...I can't see that what you drew (and, sorta, what I proposed) would present any problems, inside corner or not. Cut rabbet in each, from top on one, from bottom of other and lay it on. You are "coped" automatically.

I've done exactly that many times.

And, of course, if you were to choose to do that in this instance structurally you'd want the rabbet to be on the top of the center piece so the unbroken surface is on the bottom for maximum strength. The problem w/ this is that it would require the edges be parallel or one end to go in first followed by the other for assembly or putting one of the two tops on after in place which wouldn't be all that convenient.

So, given the top is 1" material, the choice would be to make the rabbet fairly shallow so there's a thick-enough lip to support the way and the aforementioned unanticipated weight issues above.

Which, all in all, is why I suggested the moulding as the primary support and the spline to serve as the alignment initially...

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See photo: