Plasma cutting Oversize shapes

[7 J style]

I am using a Hypertherm 45xp ,inkscape,sheetcam,Uccnc. I am trying to cut a 2in square. I think its in the Uccnc settings i got this system used my dimensions in sheetcam shows 2in. Im getting a 2in square that is cutting a 2.5in square. I looked at kerf width, tool dia. No change in moving these settings. Any direction would be great.

[cuttinparts]

Does your Uccnc software show you the size of the part on the screen? If so, does it show that the part is 2"?

[acourtjester]

You most likely need to do the axis calibrations on the table, simple check is to tell the X to move 5" and check to see how far it actually moved. Do the same for the Y axis. The steps per setting needs to be correct to move correctly. When you do this move longer distances to get smaller correction to show toward the end of the calibrations.

[adbuch]

I agree with Tom. You probably need to set your "turns ratios" so that when you tell it to move 2.000 inches it actually moves 2.000 inches. I have done this with Mach3 and Centroid systems, but am not familiar with your specific uccnc system.

David

[acourtjester]

This is what I use to calculate the steps per for the table movements. I mark the rail for the axis I am calculating for the starting point and then use the MDI to enter a distance to move. I then measure how much it actually moved and use this formula to calculate the new value to place in the software for the steps per for that axis. I repeat this until I have the exact distance matching what I entered and measured. I normally increase the distance to almost the full length of the axis travel as I finish as longer distance equals smaller errors to use to correct for in the calculations, to the exact value. The attached image shows where in UCCNC to see the steps per for the calculations. I don't know how to use the calibrate function in UCCNC shown in the image.
FORMULA FOR CALIBRATING
Steps per Unit on an axis
Steps per unit in MACH
Current Setting in Steps per UNIT = Sc
Actual Distance Traveled = Dt
Commanded Distance (you entered) = Dc
New Steps per Unit value = Sn
(Sc X Dc)/Dt = Sn
Sn is in steps and will probably a decimal number
Set the decimal amount to 3 decimal places

[7 J style]

Ok I can’t believe I got but i got it!!! to calibrate was easy mark a start point the put in movement measurement and hit start, then measure distance torch moved put in distance and it calculated the step units. Now it cut a 2" square on X and Y axis. Thank you soooo much going to make this machine work.

https://plasmaspider.com/download/file. ... w&id=88095

[acourtjester]

Happy to help, some pay back for the help I got.

[weldguy]

Well done guys. Love seeing this sort of thing.