mach 3 scaling issue

[JAZZCNC]

Can't see anything wrong there and it loads into mach fine here. Roughly 54mm square.

If you can't find any obvious reason ie Step per Settings etc then I'd install Mach3 again seen daft things like this happen before. just install over top of existing setup all settings will be retained.

Sure this won't be the case but you haven't set scale factor have you.? If you have the scale LED's will be flashing at you so will be obvious.

[terry1956]

Hi.i am looking at the mach3 manual, but it as nothing on scale. In what position are the scale factor leds. Apart from looking at the scale factors, and reloading mach, is there anything else I need to look at. As stated the tool moves correctly when setting the auto measurements of axis. Thanks for helping.

[JAZZCNC]

See pic for scaling location.

To test if moving correct distance use the MDI and command a move. Try this.
First Zero the axis you wish to move. In this case lets say X axis. Type these commands in order written below push enter after each.

G21
G90
G1 X54 F500

If it doesn't move correct distance then it can only be that your Steps per are not set correctly.

It's very easy to calculate the steps per. Take the micro step setting on the drive and divide by the pitch of the ballscrew. If uses ratio this will need be taken into account.

[terry1956]

Just completed the test.the tool pointer moved 56mm, so a little bit of adjustment needed.but this does not answer why the machine is cutting far to large.the fault must lay in the way mach 3 is reading the artcam software.could it be that the g code needs to be in a different format .....

[JAZZCNC]

Terry the code is fine I loaded it into mach it cut air perfectly.

I wouldn't mess around just install mach again. Then try but first make sure the steps per setting is correct. This figure isn't just some randon number or one that can be close. It must be exact or the machine will never move correct distance.

[JAZZCNC]

There is one thing you could try but I don't think it will be the problem but hurts nothing to try.
The code uses IJ mode for the arc moves so could try changing the IJ Mode setting in general config. However usually when the IJ mode is wrong you'll get large circles on the screen.

Go to General Config change the IJ Mode to opposite of what it's set to now. See pic where to find.

[Neale]

I was looking at Terry1956's machine earlier this week. It's a Sieg X1 and appears to have 3mm pitch trapezoidal leadscrews. Drivers are set to 1600 microsteps/rev, and Mach3 was configured with 533.333 steps/per. System set to mm, of course. We didn't actually measure movement at the time. I would double-check that the steps/per figure is still set OK, just in case something has changed there. Certainly not obvious why that gcode shouldn't run just fine, though.