Trapezoid style dining room table leg question(s)

[Rob Dykens]

Does anyone have an idea of what angle the legs would be cut at in the examples I have collected in this link? (https://imgur.com/a/zU7exI4) I'm guessing somewhere around a 10 to 15 degree bevel?

Drawing up plans for a walnut dining table to build this summer. Top will be 2 inches thick (minus however much the jointer and planer eats) and legs will be approx 4x4 inches square.

Looking to fabricate the legs using bridle joints similar to this example, if possible. (https://imgur.com/a/U0I8rpT)

One last question, looking at one of those examples in the first link I posted, it appears that the builder merely has 90 degree angle brackets intersecting where the leg meets the tabletop to fasten them together. I would assume that the tabletop portion of the bracket has elongated mount holes to allow for table top width expansion and contraction, however do you think this is strong enough to prevent lateral shifting, or leg wobble... the legs don't appear to have any bracing tying them together at all which concerns me.

Thanks in advance for your time and thoughts.

[Jamie Buxton]

The first two pics in your collection are straight from the end of the table. You can directly measure the angle off the photo with little error.

If you're going to cut bridle joints in 4" members, you will likely have to cut them with a bandsaw; a 10" tablesaw cuts only 3" tall. The other way to make a bridle joint is to laminate the stock from three pieces of wood, arranging them to form the bridle joints without further cutting.

About your example concerning hygroscopic expansion... I'd bet there are no slip joints there. My guess is that he bolted everything tightly so there's no wobbling. (There's no need to have separate bracing on the legs here. He's using the massive top for structure. It is darn strong.) That does leave the issue of hygroscopic expansion. He's tackled that by spacing the brackets only a foot apart. That is probably okay. There's less expansion than if he put the brackets out at the edges of the table.

[Rob Dykens]

Hi Jamie,

Thank you for your insight, it helps a lot.

I hadn't yet considered that I won't be able to cut the bridle joints with my table saw (which makes things look easier) due to depth, so thanks for the idea on the assembly and glue up. Gluing up the legs in three pieces to form the bridle joints sounds a little complicated and I don't want to screw it up and waste 8/4 walnut lumber, so I am going to wrap my head around that design. I can't figure out what joinery the builder of that large walnut table used to assemble the legs, but surely he didn't just butt joint glue end grain to face grain?

So if my top were to come out at about 1.75" thick that would be strong enough to span on it's own between the two leg sections?

I was wondering why he didn't space out the brackets wider, interesting theory. The two main concerns I have is the top panel cupping or twisting due to movement and secondly, not having any tie ins between the two legs. If the table were to rack side to side at all and one of the leg assemblies let go the results would be disastrous.

I am willing to buy extra lumber and somehow fit aprons or cross members between the two legs, but I just can't envision a clean way to do this. You're of the opinion that having aprons or bridging the two legs together is unnecessary?

Thank you again for your time.

[Steve Jenkins]

Another way to join legs is with large dominoes AKA floating tenons

[Prashun Patel]

He prob put those angle brackets close to the center to avoid having to make elongated holes.

You should make up a small mock to make sure like the look of the legs. I'm going to guess they are 7-10 degrees.

If it were me, I'd make that table a trestle table instead of the angle brackets. A center trestle about 6-7" tall running through the center, or even better, two running about where the angle brackets are will give good support and flatness to the table, and can be bolted directly to the underside. You can add recessed u channel or cross braces to support the table mid span without interfering with the user's legs. I've done that and it works great. For cross-grain strapping, you can mill oversized holes in the iron, and lag bolt it to the top through a washer or two.

[Rob Dykens]

Hi Steve,

Join legs as in join the 4 pieces of the trapezoid to each other, or join the leg assembly to the table top panel?

I do have a Domino, albeit it's not the XL model.

[Rob Dykens]

Hi Prashun, thank you for stopping by.

I am going to make a mock up, I have some spare 2x4's lying around to dial the angle in. Thanks for your estimate on the bevel angle.

I used to be able to see pictures on here, but it unfortunately appears I no longer can. I don't suppose I could trouble you to upload it to imgur by chance so I can see what you're referring to?

How would you fasten the 6" to 7" tall board that travels from the center of one leg to the other leg? Mill a dado through the inside face of each leg and fasten it into the dado slot?

[Kevin Jenness]

Several options for joinery on the walnut table base including mortise & tenon and spline tenons.

An 8/4 top will cover a long span unsupported by stretchers, the question is how to stabilize the leg structure and control the top's movement given the overall design. If you are ok with the angle iron brackets I would suggest putting them on either side of the legs for racking strength, perhaps using larger (3"x3"?) angle, and attaching them at the center of the leg structure with fixed holes and at the ends of the legs with slotted holes under the top. Do a mockup to test out the idea. There is a reason most tables are designed with stretchers, but no doubt you can come up with a workable solution.

[Steve Jenkins]

Hi Steve,

Join legs as in join the 4 pieces of the trapezoid to each other, or join the leg assembly to the table top panel?

I do have a Domino, albeit it's not the XL model.

parts of legs to each other. I think The top should be removable

[Rob Dykens]

Hi Kevin

I am leaning towards having the two legs bridged some how, just need to figure out the best way to do so. I am rather hesitant on whether the angle brackets would prevent side to side racking.

[Rob Dykens]

OK I'll look into dominoing the four pieces of the leg together. Yeah if the top were permanently attached to the legs it would be almost impossible to move.

I will have to come up with a way to clamp non square assemblies but I guess I can just cut some wedges