CNC Plasma Cutter Iteration 1: OK, we have motors, and a controller for them. Now what?
Ok, so the HobbyCNC controller board and stepper motors have proven to work excellent on their own, sitting on my tech bench. What is the next step? Well, build a table for them, of course!
I decided to start by designing some CAD models of some gantry carriages. Carriages are the devices that have the bearings installed, in which allow all the moving parts to slide freely up and down the axes. The first ones were going to look rough, but I assure you, the important dimensions were within .005″ of an inch. We are able to attain these tolerances due to our vintage 1950’s Gorton vertical mill, in whom we have given then name, “Gorton”, for obvious reasons. Without Gorton, I don’t think this table would have been able to hold any tolerance.
With the prototype design settled on, production began quickly after. Tegan and I made up some carriage plates to weld up and mount on a mock up 2″x2″ square tube, which is what the slides where going to be comprised up, ultimately. The bearings are standard skate bearings. These were chosen due to low cost, availability, good tolerances, and tough!
Next up are motor mounts so that the carriages can move. Nothing special about these, just simple plates to locate the motors in position for our drive belts.
As stated, belts were the route we took as a drive mechanism for the gantry. Everyone has their own opinion about which drive system is best. We chose belts, and we have no regrets. The belts have Kevlar strands in them to keep them from stretching, they have ZERO backlash, they’re quiet, won’t wear, and belts are very efficient.