So I was thinking about how we could increase rigidity with drastically increasing cost of the machine, and saying with the mostly printed theme. I thought of the one guy that had a large scale machine and added a second bar in the x and y axis to the gantry. That method wasted a lot of cutting area. Then I thought of the X axis on prusa printers… So what if we added and extra rail to the exterior x and y axis as well as the the gantry? Attached is a quick mock up of what I mean. I names it MPCNCHD lol
The only increase in costs would basically be double the cost for conduit which is on the cheap. Some extra filament and probably twice the number of bearings. I could see the cost increase for a 5’ square machine being $50 or plus an extra roll of filament of choice.
Spacing between the rails would probably need to increase as compared to my picture to accommodate the bearings and enough material to make it strong.