Alternate to a mitered corner on table top?

[jgourlay]

All, I'm sort of crossposting within the forum from this thread on mitered corners.  The short story:  I'm making a square frame table top (with a chess board in the middle, but that's not important).  This is a highly decorative project:  exotic woods, lots of geometry but very not an 'arts and crafts' type look.

I am not using veneer because the piece will see hard, messy use over the generations and I know from other furniture in our family that veneer simply won't cut it.  I had originally wanted to make the frame with mitered corners (or mitered half laps or mitered corners with tenons, etc) because of the clean, symmetrical look of the mitered corner.

I've been talked out of that because of wood movement.  Now I'm at a bit of a loss on how to make this frame (7" wide x 36" on a side) that will be strong and permanent and have a finished, symmetrical, non-rustic look.  What do you suggest?

[Gary G™]

You can do a half-lap miter with a very delicate v-groove at the miters.
These have enough glue surface that the movement could be elsewhere along the boards.
And , if there’s a touch of movement, I’d expect the V would hide it.

Another option is just miters with splines. The splines provide more glue surface and might also prevent them from opening.

How much humidity swing is there where you live?

[Big Dave]

I'm with Gary on this one. A splined miter, or a miter with just a spline cut into the corner, should be more than strong enough with enough opposing glue surface to prevent any/too much movement. If you feel a little extra might be needed, biscuits set in from the corner far enough allow for a splined corner would be plenty strong...

Dave

[ianab]

Question is, how is the centre of the table going to attach? That's where the movement will occur, and the solid wood panel (glued up chess board?) can certainly move seasonally. And if it expands too much, it will bust ANY mitred corner open, no matter how it's constructed. 

Only way I can see this working is if you "float" the middle panel in the frame. Then the central panel is free to do it's own thing, and there will need to be a small gap around it to allow the movement. The outside frame wont change in the 3ft dimensions, only the 7" ones, which will be small, and both sides of the mitre will move about the same. So at that point how you join the mitre isn't so critical. Splice, tenons, biscuits, T&G etc.

[Gary G™]

Quote “I can see this working ...if you "float" the middle panel in the frame.”
This is how I would build it.

[jteneyck]

    For the very reasons you are concerned about wide mitered corners opening, a common alternative is something like shown in the sketch above.    

Another option is to make the frame using something like 6" wide stock with butted joints and then wrap that with 1" mitered trim.  

John

[danceswithticks]

If you're not set on having cross grain end boards, but I think you are, you could just do a typical edge to edge board glue up using your 7" boards on the outside. On the bottom side of the table, three cleats going perpendicular across the grain  could be lag screwed into the top with elongated screw holes to allow for seasonal movement.  I did this on an 8 foot conference table about ten years ago on 6/4 plain sawn red oak which is not the most stable of woods and it is still flat as the day I delivered it.

[srv52761]

The issue with your original design was that 7" wide boards were approaching the widths where seasonal movement may be an issue for mitered joints.

The simple solution, then, is don't use 7" boards.
Rip the boards, then reattach them with a joint that will accommodate some movement.
Something like a shiplap or tongue-and-groove, pegged, in slightly elongated holes.
Then your outside boards will only be a couple inches wide and expansion and contraction will be minimal.

So, you will actually have two frames around your playing board.
The first, either mitered or butt, and the outside frame mitered.
Maybe a strip of inlay to highlight the joint, since it may be noticed anyway, and the inlay will draw attention the the inlay itself and not to any gap in the joint if it moves.

The total movement over the 14" width of those boards will be the same, but the bulk will be absorbed by your transitional joints. Your miters will stay tight.

[KyleD]

All, I'm sort of crossposting within the forum from this thread on mitered corners.  The short story:  I'm making a square frame table top (with a chess board in the middle, but that's not important).  This is a highly decorative project:  exotic woods, lots of geometry but very not an 'arts and crafts' type look.

I am not using veneer because the piece will see hard, messy use over the generations and I know from other furniture in our family that veneer simply won't cut it.  I had originally wanted to make the frame with mitered corners (or mitered half laps or mitered corners with tenons, etc) because of the clean, symmetrical look of the mitered corner.

I've been talked out of that because of wood movement.  Now I'm at a bit of a loss on how to make this frame (7" wide x 36" on a side) that will be strong and permanent and have a finished, symmetrical, non-rustic look.  What do you suggest?

Have you considered cutting some of the boards into 1/8" face sheets and doing the 45s over an MDF frame edged in the same wood and veneered both sides. Veneer does not have to be as thin as the commercial stuff. Done right this is every bit as durable as solid wood sans a major flood.

[Cooler]

https://www.woodcraft.com/blog_entries/breadboard-ends


There is nothing particularly "rustic" about this table with bread board ends:

https://www.1stdibs.com/furniture/tables...lsrc=aw.ds