I went to a local woodworkers club on monday to cut new plates and 2*4s for a table. The free packaging mdf plates I got, ended up getting bent when I glued and screwed them together.
Sooo - when I’m cutting the new plates and timber, one of the old and experience guys asked me what to do if the timber frame warped… he’s a mechanical engineer, and a skilled woodworker. I don’t know if I should worry - but he’s got a point - any natural/untreated timber is prone to warping and twisting over time, especially in an environment with changing temperature and humidity. So now I’m wondering if I should just drop the frame, and mount a double set of plates directly on some the feet.
I built my torsion box from plywood for this reason. But in general, I think it’s also a greatly exaggerated fear. The boards might even swell nearly the same amount. Also, the gantry rides on the top right, so if the top bows, the gantry will ride on top of the swell and it won’t matter.
In software, there’s a saying, “premature optimization is the root of all evil”. That is to say that it’s usually cheaper in the long run to make it the way it makes sense and then measure where the problems are and go back and fix them. It is certainly easier to fix software than a workbench. But you’ll have a fully functional CNC to cut parts if you want to rebuild the table later.
Thankfully, level doesn’t matter (unless you’re so far out of level that the weight of your gantry/axis generates too much strain). Flat and square, those matter…
My issue is with my lowrider table. The floor in my shop moves a couple inches up and down through the year. Causes the table to twist. My mpcnc sits on a torsion box and stays fairly flat.
Thanks for all your input! A nervous nitpicker appreciates.
I’ve come up with a new plan. I’ll use the old plate and saw it to thinner pieces that I will use as a frame and support structure, heavily supported and held into place with different types of brackets.