Cables can flex, and those small corner blocks aren't really enough, or you wouldn't have added the cables. You might want to get some 1/4" plate, maybe 18"x18" triangles, and bolt them on with angles? You can add epoxy similar to this method.Table
- Corners are braced with 1.5" slices of 4x4 steel bar-stock cut diagonally.
- Table is squared using cables tensioned diagonally between the braces.
- The 49x97 MDF substrate is supported by interlocked 3/4"plywood.
My First Router, Built in Steel
The plywood ribs aren't nearly enough to support that. You need to make it a torsion box, with both a top and bottom skin, glued in place. I'd probably use 1/2" MDF on both top and bottom, then add another 3/4" sheet for a spoilboard. Unlesss you have another plan for work holding.
By making it adjustable, you're probably making it less rigid, but I guess it depends on the design. But I think changing the height will be a hassle.- The ganry has 3 height settings, increasing rigidity and reducing distance from bearing to bit when cutting ply.
- Height settings offer 3", 7", 10" of clearance between top of substrate and lowest point on gantry
Why do you need 10" of travel with a 2" bit?? Not sure if I've seen anyone with a high gantry actually use it.Z-axis
- The Z-axis has a range of motion that allows a 1" bit to reach the substrate from full gantry height, and allow a 2" bit to raise high enough to clear the lowest point on the gantry. 10"+ of travel
Imo, you should shoot for a minimum of 3:1 gear reduction. 4:1 is better. It looks like you have much less?
And if you're going for 49.5" of cutting area, add another 1-1/2" or so. A lot of sheet goods come 49", and you might want to be able to use a larger tool on both edges. And adding another 2" should cost anything more.