Let me start off with saying this is New undiscovered territory for me. I recently purchased an OX 1500 x 1500 system from an individual and installed the OBs Control software to run it. I gone through the setup and thought that I had it correct. GRBL Setting (Below) $0=10 ;Step pulse time, microseconds $1=255 ;Step idle delay, milliseconds $2=4 ;Step pulse invert, mask $3=4 ;Step direction invert, mask $4=0 ;Invert step enable pin, boolean $5=0 ;Invert limit pins, boolean $6=0 ;Invert probe pin, boolean $10=0 ;Status report options, mask $11=0.010 ;Junction deviation, millimeters $12=0.002 ;Arc tolerance, millimeters $13=0 ;Report in inches, boolean $20=0 ;Soft limits enable, boolean $21=0 ;Hard limits enable, boolean $22=0 ;Homing cycle enable, boolean $23=0 ;Homing direction invert, mask $24=50.000 ;Homing locate feed rate, mm/min $25=3000.000 ;Homing search seek rate, mm/min $26=250 ;Homing switch debounce delay, milliseconds $27=9.000 ;Homing switch pull-off distance, millimeters $30=16000 ;Maximum spindle speed, RPM $31=4000 ;Minimum spindle speed, RPM $32=0 ;Laser-mode enable, boolean $100=53.333 ;X-axis steps per millimeter $101=53.333 ;Y-axis steps per millimeter $102=400.000 ;Z-axis steps per millimeter $110=7500.000 ;X-axis maximum rate, mm/min $111=7500.000 ;Y-axis maximum rate, mm/min $112=500.000 ;Z-axis maximum rate, mm/min $120=100.000 ;X-axis acceleration, mm/sec^2 $121=100.000 ;Y-axis acceleration, mm/sec^2 $122=10.000 ;Z-axis acceleration, mm/sec^2 $130=1250.000 ;X-axis maximum travel, millimeters $131=1250.000 ;Y-axis maximum travel, millimeters $132=60.100 ;Z-axis maximum travel, millimeters I have the limits turned off as well as the homing (another issue for another time) The alleged hardware configuration of the system that the individual stated is: 1, 1500mm x 1500mm ox cnc machine 2. double gt3 6mm belts on all axis 3. z axis has been upgraded to a couple beam extrusion with 8mm lead screw and double acme nuts combined with the taller adjustment on the end plates allowing for 7in z travel 4. The steppers (see photo) 5. 500w air cooled dc spindle My issue is that I attempted to cut a test piece to see how it worked. The dimensions on the cut were on, but the star that I attempted to cut was all out of whack. It is suppose to be a perfect five point star. In the simulation it shows it correctly, but as you can see for the image of the cut, it did not turn out at all right. So if anyone can help this FNG out it would be much appreciated. Please bear with me because like I said this is new and undiscovered territory for me in regards to an openbuilds build and the control software set-up. I have attached some images.
Gary, It appears to be a MKS DLC v2 controller. Have no clue on the drivers. The markings that I can see has MKS on it. The drivers in the photo appear to match the MKS LV8727, Here is a photo of the inside of the box.
My guess would be loose setscrews on the pulleys. Try rotating the design 90 and 180 degrees and running another cut to see what you come up with. Cutting circles is another good method for isolating problems.
Welcome to the world of CNC. I'm guessing that the person you bought it from had never run it or if they had got frustrated and gave up. If so, I would make sure all the screws and bolts are tight, make sure the structure is true and square, look for flex and slop, check each axis for square. etc. The spindle should not move when you push it. At lease, it shouldn't feel loose. These aren't terribly complex machines so you should be able to get it working well pretty quickly. I'd invest in a machinist's square, a good digital caliper and maybe a dial indicator. Not terribly expensive and will help you get your machine up to snuff.