I left the last log of this project with Promises of mark 3 in action. Mark 3 work, brilliantly but the ridiculously small working area was an issue.I wanted to make Rc plane kits from large depron sheets. So as soon as i got mk III running , tried a few test cuts and dismantled it! I wanted to rebuild the big one ( mk II ) with the speed of mk III.
Here is a pic of MKIII before I added the Z axis assembly.
I redesigned the mk II Gantry and optimised it for speed.Gone are the heavy mdf panels, a;replaced by light pine beams and open structures, i've also replaced the top and undercarriage with 4 tensioning m6 rods instead. I've learnt that designing ev
erything from the start and then relying on the parts to fit as planned never goes to plan, so all the carriag
es are adjustable using the thread rods. The Gantry is now super light, adjusted for minimum friction at minimum wobble.
I have geared up the stepper motors by 5, the transmission is via a timing belt and
abs timing pulleys.I have also changed the cutting bit for a 6mm 2 flute dremel router bit.perfect for depron. I still have to make a video, but the cutting speed of mkIV is amazing, accuracy is pretty decent, cutting circles is pretty accurate.
I am now at the stage
of designing kits for cutting
MKIV ready to accept her next assignment. Next step: A dust collection system and plastic extruding head! turn mark IV into a repstrap!