Hi folks,
I'm working on the biggest project I've tackled and could use some advice. It's a trestle table designed by Daniel Chaffin that I found in FWW. It involves six large M&T joints, two for foot-to-post and four total for apron-to-post.
Chaffin big table 2.jpg
Cutting the mortises is no problem for me. Router template plus spiral upcut bit, chiseled square.
I'm more vexed by the tenons. I don't own a tenon jig, and the pieces are too big anyway. So I'm doing things with a dado blade. With the post-foot joint, I didn't sneak up the cuts too close (scared of a screwup), so I had more than the usual fine-tuning to do. Keeping the tenons square while fine-tuning has proven hard. I am paring with chisels and a mid-sized shoulder plane I borrowed. Here's the joint and the drawing.
Post to foot mortise and tenon.jpgpost joint detail.png
Couple of questions.
What's the right way to fine-tune big tenons? With small ones, I just pare with a chisel. For these I've been using the shoulder plane, but it's narrow and doesn't keep things square. Is the proper tool a rabbet plane? I ask because I want to do it better for the aprons. Drawing below. I'm more concerned about these because they are through tenons.
apron joint detail 1.pngapron joint finished.png
Second, what's the best way for figuring out *where* a big tenon like this is tight? With so much tenon, it's hard to figure out where to pare.
Third, more of a theory question. How much of the joint strength here comes from the long-grain to end-grain part of the M&T joint? I am wondering whether I can get the cheeks of the tenon right and then give myself plenty of space on the edges. Sort of like the way dominos work, with very little contact on the edges.
Thanks! And much thanks to Dan Chaffin who answered emails to help me scale up the design.