Is this too wide?

[RayV]

My buddy wants me to make him a shelf that will fit into an opening he cut in a wall. The wall is 7" thick drywall to drywall and he wants 1

1/2" overhang on either side. He also wants it about 1 1/4" thick. The width of the opening is 48" to which he wants to add 1 1/2" to each end so the shelf wraps around the opening. Here is a basic diagram: (fancy fixed width font drawing follows) _________________________________ /_ _\ | | _| |_ \_________________________________/

This shelf will be installed in his condo in Florida and my concern is the wood movement may cause the shelf to split since it will be prevented from shrinking by the walls. He wants a wood without the pronounced grain of oak. I'm thinking maple or cherry. Whatever it is it will probably not be stained and just coated with clear poly.

So I need a piece of wood 10x51 that is stable across its width without eye-jarring grain, any recommendations?

To install it I'll probably have him run a bead of liquid nails down the center of the shelf, any better way?

[RicodJour]

I'd use an adhesive with more give to it - a silicone or Geocel. If the interior corners are drilled prior to cutting the notches to provide a bit of a radius, and the ears aren't wedged up against the wall so they have a bit of room to move (a little over a 1/16" is probably all you need) and not caulked, you shouldn't have a problem. Maple would be fine. The cherry is going to darken with age a fair bit, so you should see how your buddy feels about that. Almost any wood would do if the ears aren't restrained from moving.

R

[Doug Miller]

[snip]

If you mill the shelf at this time of year in just about any part of the US

*except* Florida or the Pacific Northwest, then move the shelf to Florida, it's going to *expand* when it gets there, not shrink.

Soft maple or cherry would be fine; expect a change of approximately 1/8" in width. Using quartersawn lumber would cut that in half.

Soft maple, cherry, or yellow poplar.

That should work fine.

[Toller]

You are only talking 7", so the worst wood will move 1/8". And if it is wood frame, that will move the same as the shelf.

[RicodJour]

Not at the same time/rate if that framing is covered by drywall. But I agree that the amount of movement will be small and not a great issue to deal with as long as there is nothing to restrain the wood from moving.

One more thing - the OP didn't mention how thick this wood was to be, but a single line of adhesive down the middle of the framing won't keep the wood from curling. That's why I was suggesting something with some more give than construction adhesive, and why the adhesive should cover the wood framing, not just the center line.

R

[RayV]

So we go to the lumber place at lunchtime to see what they have...

My buddy can't decide between Cherry, Curly Hickory, Curly Maple, Kauvula or Bubinga. And he doesn't have the 'boss' with him so I won't trying to run any of this through my planer anytime soon. He liked the Bubinga best but it was $150 compared to $43 for the Curly Hickory.

He is only wants a roundover for the edge treatments so that shouldn't be a problem. How about running any of the above through my planer (Delta 22-580). I've only ever worked with cherry out of the above and it planed fine. The Hickory looks like it wouldn't plane well, at least with a home planer.

[C & S]

I did somewthing very similar for a buddy about 6 years ago... It was only an interior 2x4 wall so I did not sweat the expansion.

It was basically a "window sill" between his kitchen and livingroom.

I did find it impossible to install a well-fitting, premade H-shape though. I implemented it as two pieces, glued together in place. Unfortunately this approach pretty much dictates finishing in place

If you rip one board and glue it back together, the seam can dispear completely. This will also give you an opportinity to let the "ears" into the drywall. This would completely eliminate the whole movement issue as the "mortises" for ears could be a little extra deep.

regards,

Steve

[RayV]

I told him that getting it to 'fit' is going to be next to impossible especially after you factor in the irregularities of the wall. Even back-cutting the notches is not going to give a great fit.

That said I'm thinking that trying to even out two pieces glued together in place would be even harder. Did you use dowels or biscuits to line the halves up? What about sanding the top smooth between the walls?

[Stephen M]

I too, tried to make it work including back cutting. That plan was doomed.

No. But I never use "allignment aids" when guing up. I just start clamping at one end an work my way across. I find that process good to about the thickness of a playing card. I can sand or scrape that flush in a jiffy. One seam at a time though (maybe two).

Yes, I sanded.

What I did do was cut some clamping blocks with the reverse profile of the sill so that I could glue up the sill in place with the clamps straight across the joint. The sill had a simple bevel so the calmping blick looked like this:

_____ ___ | __ / | _____|

-Steve

[Roger Shoaf]

This might work. Rip the uncut board down the middle and after flattening the edges with your jointer use biscuits but do not glue it. Install some cleats on the underside and clamp the joint via the cleats. Now run the top through the jointer to clean up the seam. Disassemble the joint and reassemble with a piece of saran wrap or wax paper in the seam. Apply the finish, and when dry you should be able to disassemble the shelf.

When you go to install, first take a board a little thicker than your shelf with a utility blade fastened to the top of the board. Lay it on the horizontal sheetrock and use it to undercut the sheetrock.on the sides back to the studs.

Now insert both halves on your shelf into the slot and glue the joint. If you use white glue, you can clean up any ooze while still wet with a damp cloth.

Once dry squeeze a little silicone in below the shelf and perhaps a brad or two. Once this is set, use a little caulk at the top edges where the board slips under the sheet rock.

This should give you a nice install and keep everything a little flexible in the event the board expands or contracts a bit.

Be sure to post back with how you ended up doing this job, and how it came out.

[RayV]

I just had the 'customer' read this thread. He doesn't want to mess around with the drywall or gluing the shelf. So I'll just cut it from a single board to match the template he made.

He has decided on Bubinga for the shelf. I've never worked with this stuff, any tips or suggestions on finishing. The wood won't be stained and will get sunlight a few hours a day in a condo in Florida that is at 90 degrees 80 percent of the time and 70 degrees the rest of the time.

[Roger Shoaf]

OK I guess if he wants what he wants then give it to him.

Here is the trouble I see. In order to install this you need to twist the board diagonally in order to slip it in between the two sheet rock covered studs. If the board is 1 1/2 inches thick and the dimention is 48 inches wall to wall and the board is 48 inches and has ears that stick outon each side, your friend is going to get a geometry lesson.

[RayV]

Yeah, he figures backcutting the notch where it butts against the studs will give enough clearance to angle the piece in. Probably, but I think the ears will be the real problem. Getting them to slide down along the wall without gouging the drywall and still be snug when in place will be next to impossible.

Oh well, his money and drywall...

[Stephen M]

I guess he'll be messing with the drywall one way or another. ;-)

[Roger Shoaf]

Ray,

Another thought crossed my mind, since your shelf will be 1 1/2" thick if instead of gluing it in place perhaps you could make it so it would screw together.

Rig it with some dowels or biscuits and you could angle drill from under the lip to turn screws, to clamp the two halves together.

In the alternative to drilling at an angle, you could drill it straight and make some wood bungs to cover the screw holes.