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View Full Version : Wishbone Trestle Design help needed



Prashun Patel
10-22-2014, 9:47 AM
I made this scale model of a dining room table I'm planning to make. I'm concerned about the strength.

The legs will be about 30" tall and the distance between the feet will be 30".

The table top will be 36" x 96".

I'd like to make the legs about 3" thick, tapering to 2.5" at the bottom. The stretcher will be 10" tall.

I think as-is, that stretcher will be ok. However, I would like to arch it in the center, or even split it into multiple stretchers.

Will this be sufficiently stable?

Thanks for any advice.

David Hawxhurst
10-22-2014, 10:26 AM
if you use the rule of 9th the stretcher will have very little load and will be more or less just keeping the legs from falling over. i would fell comfortable with arching and/or multiple stretchers.

rule of 9th for trestles: 2/9 ths over hang on the ends and 5/9 ths in the middle. this allows the table top to self balance and helps prevent sagging in the middle.

Jamie Buxton
10-22-2014, 10:52 AM
You can arch the bottom edge of the stretcher with little change in the stability of the table. Structurally, the stretcher mostly prevents lengthwise racking. If the stretcher height at the ends stays 10" tall, the stretcher still acts as a big triangular gusset even if the middle is only a couple inches tall.

I like the idea of arching the bottom edge of the stretcher. It repeats the curviness of the legs. Nice design.

Pat Barry
10-22-2014, 11:33 AM
I agree that the stretcher is disproportionally wide for that design table so leaning it out and arching it is a great solution. Also like the tapered leg idea. The taper will add a nice aesthetic to the end view. I do think the cross-wise bracing might be a bit too thin though. I would want the center 2/3 of those braces to be thicker and then taper toward the edge of the table-top.

Prashun Patel
10-22-2014, 11:51 AM
Great points, Guys. Thanks. I agree I need to beef up the top supports.

I'm planning also to bevel the insides of each leg 3-5deg, so that the legs rake backwards. I didn't show that in the mock-up.