Serious issues with code in mach3...

Problems and questions
1

I am having issues with my code generated in sheetcam and mach 3, everytime i try and run a part, it throws warnings regarding soft-limts on the Z axis.

I am homed to the top position so my limits are max=0 and min=-75

I am using the torch with scriber post processor because i want to probe the sheet surface before each cut.

I have been battling this for a while now but ignoring it and just ok the message as i have only been testing my hardware etc.

I have attached a simple tap file, if someone can look and see if there is a problem in it at least i might know if its sheetcam or mach3 thats wrong.

Many thanks
Dave

2

I think the soft limit warning is due to the probing move. During simulation Mach does not know when the probing move will end so it uses the maximum possible move. Each time it probes it moves further down, eventually running into your soft limit.

There isn’t really any good solution to this apart from turning off soft limits or disabling probing.

3

Thanks Les,

It’s not the news i wanted but it sort of makes sense now.

turning off limits on the Z axis is dangerous as there is only one physical limit switch, the downwards direction is unprotected at its extent.

this may or may not be an issue in production, im still messing with a pen in the toolholder, i guess the danger will only arise if i start a cycle with no metal resent on the bed, the torch will likely miss the bed supports and allow the axis to over travel.

I suppose a physical lower limit switch with the lower soft-limt changed to something arbitrary like -5000 and the upper soft limit remaining at zero is the only real answer???

4

Ok im baffled now, my last suggestion will not work.

The error is coming from Z-Max which is zero so the code is sending the head up above zero and not down as i guessed earlier.

Is there a way round this without disabling Z axis soft-limits?

Dave

5

I don’t know of any way around the problem. Ignoring the warning will work and the soft limits should operate correctly when the code is running. It just falls over in simulation.

6

Ok no worries, I have disabled the soft limit on z axis as the message requires keyboard use which means I can’t start a cycle from the pendant.

I don’t think soft z is going to matter, it’s the axis least likely to be ploughed into an end stop.

At least I have a grasp on what’s happening.

Thanks for helping.