Checks in end grain

[mandoboy]

Well, bummer, but that is how one learns. It is funny that I was thinking about wood movement alot for some cabinet doors in my next project, but I hadn't thought about it for a top.

I guess I will paint the little table and enjoy it while I can. I was pretty happy with the way it turned out for my first try at mortise and tenon.

Thanks for the lesson Nick. I will read your article tonight.

JeffG

[kalynzoo]

Truly Nick I'm impressed and enlightened. Being new to this site, I really didn't expect "woodworking 101" from the Academy. I am impressed and I did enjoy and learn from the article. Thank you.

[a1gutterman]

Hi Gary,

Truly Nick I'm impressed and enlightened. Being new to this site, I really didn't expect "woodworking 101" from the Academy. I am impressed and I did enjoy and learn from the article. Thank you.

Isn't SS a great company, and don't they have great people, from Jan and all the others at the end of the phone line, to Rick Davis, the TA instructor, to Drew and Nick?

[Nick]

Thanks for the kind words, folks. Jeff, just in case you need a reference for a more traditional way to join tops to tables, here's a page from one of the projects we cover in the Academy.

[ATTACH]870[/ATTACH]

With all good wishes,

[mandoboy]

Nick thanks for the Instruction.

I wanted to run by what I did in the corner to see if it would have been ok had I not glued it as well. I made some corner braces which were screwed and glued into the aprons. Then had a screw hole in the center to screw the top down.

I felt this gave the table some torsional stability.

Jeff

[Nick]

Corner braces are a good idea in any leg-and-rail construction that will be subjected to a lot of racking forces -- what I suppose you are calling torsion, although there is more to racking that just twisting. You frequently see chairs and large tables with corner braces; I would advise it's coals to Newcastle on a small end table. It doesn't do any harm, but it's not necessary.

If you choose to attach the table top by driving screws up through the aprons or braces, then you must allow for the wood movement. The rule of thumb is that the wood will move 1/4" for every 12" across the grain. The shank holes through which the screws pass must either be enlarged or oval-shaped to permit this motion. Then, when you screw them down, you must not make them so tight that the table top cannot slide on the leg-and-rail frame.

If I elect to use screws to attach a top to a structure, I normally turn the top so the heartwood (inside of the tree) faces up. The wood will tend to cup by raising in the middle -- the edges will curl down. (Wood cups in the opposite direction of the annual rings.) I fasten the top to the structure with tight screws in tight holes at the middle. This prevents the top from cupping and divides the motion so the top will expand and contract from the middle. The screw shank holes elswhere on the structure are oval-shaped or "slotted" in the direction of expansion and contraction. But instead of having to make shank holes that allow for 1/4"-per-12" movement, you can make them smaller by half.

With all good wishes,