Through tenon and wood movement

[Warren Wilson]

I am pondering a table design with a through tenon holding the lower shelf. The tenon will be about 5" wide and the cross piece into which it will fit is about a foot long. I've seen this design on the web, and I am wondering about managing wood movement -- is it something I should worry about with those dimensions?

table.jpg

[Wayne Lomman]

Warren, if your timber is dry it won't cause any catastrophic problems. The mortise long dimension won't change significantly over time, so make sure the tenon is well dried and it won't end up with a hap at the ends over time. You are more likely to have movement issues with the breadboard ends. Cheers

[Warren Wilson]

Thanks, Wayne. In the design I saw the tenon was also pinned. It looked like a classic cross-grain situation, but the execution was so nice, I doubted the craftsman missed it.

As for the breadboard ends, they will be fitted over tenons on the table ends to accommodate seasonal movement -- fastened only in the centre.