Making a Table Top

[joe webb]

Hello All,

I have some left over red oak flooring planks from an older project. They have been in my garage for a year now and I do want that space back. Not sure what to do with them. They 3/4" thick with a wavy bottom surface.

There are several long planks so I thought I can make a table top for my electric sit-stand desk. It's just a matter of unscrewing the legs and re-attach them to the new table top.

I am thinking 24"x80" top using 4 planks that are over 90" long. Then I can cut another plank to make a 2" thick border.

Is there any chance red oak would sag? If yes, how much of reenforcement below the top is needed? I can make a frame/grid from plywood underneath.

Thanks

[Jamie Buxton]

How far apart are the supports for the top? Surely they're not all the way at the ends, 80" apart, right? The amount of sag depends upon the length of the unsupported span.

[joe webb]

The 2 legs are independent thus I can play with the distance between them. Right now, on my current desk, they are 42" apart supporting a 1" thick melamine top at 48" long. No sag at all after 5 years.
But with a longer table top, I would like to spread the legs out as far as possible. 56" apart would leave 12" from each end

I was also thinking of glueing the planks to a piece of a plywood to double the thickness. But my concern is that add quite a bit of weight which is not good for the electric motor of the legs.

[Jamie Buxton]

Remember that solid lumber expands and contracts across the grain. It isn't a lot, but it is enough to cause trouble. Gluing the entire 24" table width to plywood is likely to be a problem. If you want to stiffen the top, you could run the plywood from support to support, and rest the oak top on it. You'd fasten the oak to the plywood only along one long edge, say with glue. At the other long edge, you want a sliding joint. That's easily done with screws going through oversize clearance holes in the plywood, with a washer to prevent the head from pulling through the hole.

[Jamie Buxton]

Before you edge-glue your flooring together, try dry-fitting them. Some flooring edges are tilted, to ensure they fit tightest at the floor surface. If you just clamp them together with bar clamps, the desk surface will have a hump in it.

[Derek Cohen]

Hello All,

I have some left over red oak flooring planks from an older project. They have been in my garage for a year now and I do want that space back. Not sure what to do with them. They 3/4" thick with a wavy bottom surface.

There are several long planks so I thought I can make a table top for my electric sit-stand desk. It's just a matter of unscrewing the legs and re-attach them to the new table top.

I am thinking 24"x80" top using 4 planks that are over 90" long. Then I can cut another plank to make a 2" thick border.

Is there any chance red oak would sag? If yes, how much of reenforcement below the top is needed? I can make a frame/grid from plywood underneath.

Thanks

The 3/4” boards should be fine as long as you create a frame below (in addition to the thicker edge - 2” thick seems a mite excessive! ) using the same wood. No ply, please. Restricting movement will lead to splits.

Regards from Perth

Derek

[Richard Coers]

A border around solid wood is a disaster waiting to happen. Even when you lay flooring, they tell you to keep a gap around the outside so the wood can move. Same goes for fastening to plywood, something will have to give with seasonal movement. As mentioned, the bottom of the tongue and groove joint doesn't touch. The only surface that touches on the sides is the top lip. Good idea to repurpose, but you have a real task ahead to make that material work.

[joe webb]

Remember that solid lumber expands and contracts across the grain. It isn't a lot, but it is enough to cause trouble. Gluing the entire 24" table width to plywood is likely to be a problem. If you want to stiffen the top, you could run the plywood from support to support, and rest the oak top on it. You'd fasten the oak to the plywood only along one long edge, say with glue. At the other long edge, you want a sliding joint. That's easily done with screws going through oversize clearance holes in the plywood, with a washer to prevent the head from pulling through the hole.


Thanks Jamie. I got your point. I suppose I would also use oversize clearance holes for attaching to the strip of plywood going along the short edge.

[joe webb]

The 3/4” boards should be fine as long as you create a frame below (in addition to the thicker edge - 2” thick seems a mite excessive! ) using the same wood. No ply, please. Restricting movement will lead to splits.

Regards from Perth

Derek

Thanks Derek. The 2" edge if for concealing the frame below. 3/4 for the flooring itself and 1 1/4 for the frame.

[joe webb]

A border around solid wood is a disaster waiting to happen. Even when you lay flooring, they tell you to keep a gap around the outside so the wood can move. Same goes for fastening to plywood, something will have to give with seasonal movement. As mentioned, the bottom of the tongue and groove joint doesn't touch. The only surface that touches on the sides is the top lip. Good idea to repurpose, but you have a real task ahead to make that material work.

Thanks Richard. Your comment about only the top lip making contact, is the concern that it won't stay flat overtime? I saw in several videos, they put a board at both end and attach it firmly with glue and a loose tenon. I thought it was standard to have end boards attached. But I do understand it will go against the wood expending and contracting across the short edge.

During my stairs remodeling projects, I glued these planks to make some wide winder steps. Just standard wood glue and it was holding pretty good.

[Tom Bender]

Using flooring for a desk top will give you a desk with gaps at the joints. To write on it you will need to add a desk blotter. If that works for you, just install it like flooring, with a small gap in each joint. If your boards are 4" wide and well acclimated, 1/16" if assembled in summer, a little more in winter.

[joe webb]

Thanks Tom. Now I am concerned about my stairs installation. I used this flooring to make stairs winders. I used wood glue at the joints and PL premium to attach to subfloor. After 3 coats of Poly, it is flat even at he joints. My table top would be longer than the winders, but for sure not as wide.

[Tom Bender]

Could be a problem but maybe not. Nothing to do now but watch and worry.