I was just coming up the learning curve with Mach3 when the pandemic hit. After 15 months away from my machine, I find that I'm having problems with setting machine and work coordinates (probably due to fumbling fingers here). It's depressing how much info you can forget when you don't use it. My Mach3 is set up in millimeters, but when the axes move, the numbers displayed are much lower than what I'd expect. For example, when the Z axis moves up 20 mm (as measured with a steel tape measure), the readout shows a movement of only 4-point-something. Is this normal? If not, how do I remedy the problem?

Has the machine ever moved correctly?

What type of machine is it, Mill, Lathe, Router, 3D Printer

Are the axis direct drive?

Is it driving ball/lead screws, belts, rack and pinion?

Some pictures would help along with more info.

Greetings From Across The Pond, Graham!

The machine moved correctly before the hiatus. I cut mostly sheet stock (3/4" or 1/2" plywood) to make molds and forms for musical instruments, and that's where I'd like to start again. I'm using a 3-axis CNC router fitted with ball/leadscrews, two motors on the Y axis. No problems there. The computer running Mach3 is never connected to the Internet, and during the hiatus it was disconnected from mains power, so I think line surges can be ruled out. The motors are driven through an ESS Smoothstepper, and all seems to be working as it should because I can jog the machine manually. I can send you some screen shots. Let me know what views would be most helpful to you.

My feeling is that I should first ensure my machine coordinates are set correctly. I click on "machine coordinates," jog the machine to the lower left corner of the work area and zero the X and Y axes. Then I raise the Z axis near the top of its travel, zero it, then click on "ref all home." Turn off the machine coordinates so the red light goes out, and in theory I should never have to touch that again. Is this essentially correct, or has memory failed me?

I'm sure there's something simple I did wrong when I restarted my machine, or just a setting somewhere that I overlooked. But it's really frustrating to be blundering around the innards of Mach3 and not be able to find it!

If the machine is fitted with home switches then all you need to do is jog the machine away from the limits and click "Ref All Home", machine should then go to the home position and stop.

No limit switches, alas, until I can save some post-pandemic pennies. I've used soft limits successfully in the past, but would be afraid to do so now until I know I have the machine coordinates sorted out.

OK, my trouble with setting machine coordinates seems to be resolved after I remembered to set the DROs to zero and refresh the interpreter. Large DUH factor here, but that brings me back to my original question;

If my machine unit is set to millimeters, should the DROs display millimeters? If they should and they're not, what do I do?

Hi,

I've used soft limits successfully in the past, but would be afraid to do so now until I know I have the machine coordinates sorted out.

SoftLimits only make sense and work if the machine is homed to a known and repeatable location....ergo Home switches. You don't strictly
need limit switches, but if you want to be able to home to a fixed location then home switches are essential. Most people use a one limit switch (of each axis)
as a dual purpose home/limit switch. Its not a practice I favor, I would rather have separate home and limit switches.

Craig