Random movement and phantom circles

Don`t have any solutions, but couple of ideas. The following information could be completely irrelevant in this case.

I see you have a laptop with the UC100, but does the simulation mode get signals from it or the simulation is run by the laptop itself? I haven`t used UCCNC, but mach3 and laptops don`t always get along without some tuning. For example my old laptop (Dell d600 with parallel port) initially failed the Mach3 driver test. I changed my laptop ACPI to standard PC driver and it passed the test after that. If you want to change the driver I suggest doing some reading first because you might lose some laptop functions and having to insert some installation disks for certain software.

I have seen weird tool movements on an industrial CNC lathe before, also in simulation mode. The work itself was done correctly. The reason in this case was that most of the program was done without tool nose radius compensation and the compensation was switched on in couple of places when cutting arcs. The tool reference point suddenly changed when the compensation was switched on and this caused those weird movements, because the software wanted to move the new reference point back to the simulation cutting line. This did not affect the tool movement on the machine when it was cutting. Maybe something similar happens in those inner corners. The program want`s to cut an arc but the reference point suddenly jumps. And in some cases the new position is such that continuing cutting the arc takes the tool back to the cutting line.

Good points raised here - but there is no Driver test requred as the UC100 overcomes this. We have production machine running from 250euro laptop. the UC100 uses the USB to communicate so this is not an issue - we would have seen this before. The driver test issue is related to using a laptop with a parallel card - this is no longer relevant.

Good suggestion on the "real life performance" - it would be interesting to see the machine response to this? Just cutting fresh air?

One of the reasons I used a custom profile was that I had a slight problem with homing. Using the homing speeds in the default 600 profile the axis homed oK but moved into the limit switches so fast they would jam up and then not move after homing was completed. It seems that the balance between free play in my system and the movement speeds were not compatible. I played around with it for a few days trying to get the axis free play right but still had this issue or ended up with the axis too tight and ran into other stalling issues. The end result was that I kept the axis moving smoothly without play and reduced the homing speeds.

Anyway I will let you know how it goes.

cheers. Dave.

Did you complete the "Verification of the linear axes" procedure described in "First Steps" documentation available on Stepcraft homepage? Even if your system components move smoothly alone they could jam at the end positions after the machine has been assembled unless you do the verification procedure. It happened to me too. The Y axis moving assembly got stuck at the extreme end for a moment and the stepper motor together with it`s drive pulley continued to move while the belt was standing still. Wasn`t a pleasant sound.

Another good point - very important to verify the free movement of the machine in all areas of travel - but in this case the machine is working 100% and the demonstrated performance happens in demo mode when not connected to the machine.

I had tried the suspect files cutting into "air" and they had the same random behaviour.

I have just done some cutting with UCCNC version 1.0031 and without backlash compensation. Everything worked OK so I suspect that it was the backlash. I tried it with version 1.0034 and no backlash and that worked OK as well.

Therefore it looks like the backlash is the problem.

Thanks for the help everyone.

Cheers Dave.

Let me quote some more. 🙂

Another good point - very important to verify the free movement of the machine in all areas of travel - but in this case the machine is working 100% and the demonstrated performance happens in demo mode when not connected to the machine.

One of the reasons I used a custom profile was that I had a slight problem with homing. Using the homing speeds in the default 600 profile the axis homed oK but moved into the limit switches so fast they would jam up and then not move after homing was completed. It seems that the balance between free play in my system and the movement speeds were not compatible. I played around with it for a few days trying to get the axis free play right but still had this issue or ended up with the axis too tight and ran into other stalling issues. The end result was that I kept the axis moving smoothly without play and reduced the homing speeds.

Anyway I will let you know how it goes.

cheers. Dave.

Let me quote some more. 🙂

Another good point - very important to verify the free movement of the machine in all areas of travel - but in this case the machine is working 100% and the demonstrated performance happens in demo mode when not connected to the machine.

One of the reasons I used a custom profile was that I had a slight problem with homing. Using the homing speeds in the default 600 profile the axis homed oK but moved into the limit switches so fast they would jam up and then not move after homing was completed. It seems that the balance between free play in my system and the movement speeds were not compatible. I played around with it for a few days trying to get the axis free play right but still had this issue or ended up with the axis too tight and ran into other stalling issues. The end result was that I kept the axis moving smoothly without play and reduced the homing speeds.

Anyway I will let you know how it goes.

cheers. Dave.

Need to read more 🙁 sorry Tikka - you were of course correct 🙂

I had tried the suspect files cutting into "air" and they had the same random behaviour.

I have just done some cutting with UCCNC version 1.0031 and without backlash compensation. Everything worked OK so I suspect that it was the backlash. I tried it with version 1.0034 and no backlash and that worked OK as well.

Therefore it looks like the backlash is the problem.

Thanks for the help everyone.

Cheers Dave.

Good news your back in action.

Maybe try the backlash if you have time on 1.0034 and see can you replicate it?