Hey WW community. Exactly as the title says - I am making some work tables for my kids. They’ll be used for homework, laptops, etc. And they’re kids, so one can guarantee a little bit of abuse.
They’re designing them, and the “z leg” is all the rage apparently - I am in the process of designing these in sketchup, and wanted to get some input/ideas on how to make these really strong. I obviously cannot make them out of a single piece of wood, so there will be some joins, probably on the apex points. Oh and the designs currently require the apex points of the Z to be rounded …
I’m considering using half-lap bridle joints, making the Z’s angular, then routing the curves into them.
Input, advice, links to designs welcome!
I’m not sure about the dowels
The bridle joint will want to pivot and the desk acts as a big lever exerting a lot of force onto that joint with a large force multiplier.
It might be worth upgrading the dowels to steel bolts, but I don’t know a lot about the strength of wood under these forces.
If the dowel is 1” In and the Z is 48” long (no idea if that’s close), it exerts 48x the desk weight on to the dowels. You look at oak, a desk top of 50lb, a 1” dowel would be at over twice its breaking point. Two dowels and glue in the joint would will help, but steel bolts will have a much higher rating against shear here.
All of this is napkin math, and I’m not an expert at all here.
Your napkin math is good though. Excellent points thank you!