Dining Table Build – Seasonal Wood Movement

When planning out this new dining room table build, I really had no idea what I was doing. That’s probably an understatement. Luckily, about a week after finalizing the design, I went skiing with a friend of mine who is a great woodworker. Also, remember friends? Those people you got to see outside of your house back in the day? Good times.

This friend, Brooks, really changed the route of the design and probably saved the table from a cracked and warped short-lived life. While on a chairlift and over lunch, Brooks explained to me the key to woodworking, which is wood movement. I had done zero planning for wood movement, meaning that as the wood expanded and contracted with temperature and humidity changes, it would probably crack and fail. But during that conversation we figured out a path forward to account for wood movement in my design.

Yet another beautiful picture edit.

Here is a great resource for what I needed to do on the table. In a nutshell, wood expands and contracts along its width (in the direction of the blue arrows). In this design, because there are so many boards attached side by side, that wood movement can be significant, up to about an inch. If you constrain that movement, either the joint or the wood itself will fail. To allow the wood to expand and contract freely, I needed to make a mortise and tenon joint for both breadboards (the long single board on both sides of the table). Essentially, the tenon is a tongue that is about ⅓ the thickness of the full board (in green). The mortise is a groove cut into the breadboard in which the tenon sits. The middle mortise and tenon are sized to be an exact fit, with no room for movement in any direction; this pins the wood expansion in the middle of the table. Then the rest of the mortises in the table are made to be wider than the tenon. This allows the tenon to slide side to side within the mortise as it expands, allowing for a secure joint while accounting for seasonal wood movement.

To add strength to the breadboards, since I don’t want them to break the tenons off if someone leans on the table, I added haunches. These are essentially small tenons in between the full tenons; they only extend about ½” compared to the 2 ½” tenons. Finally, after adding the breadboard to each side, pins are added (dowels). These pull the breadboard onto the table tightly and prevent it from sliding off, while still allowing for side to side movement through slots in the tenons. The picture below does a great job of summarizing all of the details.

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

I can say without a doubt that that was the most I have ever learned while skiing, including when I learned to ski. I’m very grateful to Brooks for sharing that wisdom with me, and I can’t wait to show you the technical jargon as it was applied to the actual table build!

Goals Update

Over a month ago, I posted an update regarding my weight loss and workshop goals that I set last fall. The weight loss goal in particular had gone poorly, so I’m adding more frequent updates to try and stay accountable to my goals. 

Weight Loss – After getting up to go weigh myself just for this post, I am down to 171lbs! It feels great and I’m going to keep pushing hard, I might be able to see the 160s here shortly. Also, my shoes weigh 4lbs, seems like weigh too much (see what I did there?).

Workshop – Progress! I didn’t expect to make much progress this weekend on the beams, but I’ve got one about halfway done. Cutting the correct angle to meet the ceiling line was a process, but the beam has started to come together nicely. I’m hopeful I can get it installed this week and start moving on to the next four.

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