Plasma Cutter Generation 2 – Part 16: Velox Z Axis Upgrade

Z2

After over a year and a half since I placed this table into service, I have since built a proper water table for the machine, added home switches for the gantry, and upgraded the Z axis to a Velox CNC Z with a floating head and machine torch bracket.

The original Z axis that I built worked great, but shaked slightly at high speeds, and always needed to be readjusted, so I decided to go with a piece designed by a very reputable company, Velox CNC. Along with this upgrade, I will be adding ohmic sensing capabilities to the machine, since with thinner sheet metal, the floating head would push a warped section of a sheet down until the limit switch was triggered. This caused the “zero” of the Z axis to be incorrect, and therefore the torch would fire with the nozzle touching the surface of the material, which lead to poor cut quality, and quicker wearing consumables.

Now that the new Z axis is installed, the torch is much more stable, and I am confident the cut quality will improve significantly.

My next step for improvements will be:
– Possibly change to a proper linear rail, or swap the cold rolled rails out for new ones. The originals warped slightly when their mounting brackets were welded to the table frame, though I have been using the table this way for a year and a half without much affect, it does leave room for improvement.
– Creating a lower, stiffer gantry. When I first built this table, I build it with the idea I may cut on taller items, such as square tubing, metal boxes, or something similar. I have yet to do so, so the extra height only adds more of a fulcrum for the weight of the Z axis to flex the gantry, thus introducing shakes at higher speeds (300ipm)
– I may build a smaller, 4×8 table as a second table for high speed production cutting, and leave this machine alone, since at speeds under 200 ipm, even with the old Z axis, the cut quality was very acceptable.