[VaderSpade]

Because all axis are involved Tormach thinks the problem is coming from the computer, either software or hardware.

My middle son is a computer wiz, he works for Microsoft in software development. He has also been taking classes on CNC at the Tech Shops, and wants to build his own 3D printer soon. He will be here for Christmas. I’ll have him download the new control software before he leaves home, and we’ll install it when he gets here. I’ll only run programs from the hard drive, and we’ll see how it goes.

Have a Merry Christmas and hopefully we’ll figure this out.

Thanks for all the help.

[benji2505]

Check whether all your boards are grounded and d-check the ground wiring. Also make sure you use the short, shielded printer cable. I would guess that you have some noise in the secondary circuit.

[VaderSpade]

I'm still having major problems. Tormach can't seem to figure it out.

[benji2505]

Check

1. Whether all ball screws are lubricated. If you wipe across them with a finger you should have a light oil film on your finger. Might sound ridiculous, but is a maybe. What lubrication oil do you use?
2. Take a voltmeter and check all voltages between the hot wire and the ground. Compare these values to the values in the values in manual or post them.
3. Check the voltages coming out of the secondary supplies. Are they 12 or 24 Volt?
4. Check the voltage going out towards the steppers (breakout connections). What is the value?
5. Check visually all wiring. Any rub-offs of the insulation? check all ground wiring.

6. Don't loose patience or humor. Always look at the bright side of life/it: you get a comprehensive tour of the mill. If you return it, you start from scratch with the next mill

benji

[philbur]

I'm sure Tormach are way ahead of this but anyway here goes:

1) Does the spindle stop at the same time as you lose axis control?
2) After the stop do all axis still respond to MIDI commands?
3) After the stop do you still have power into the bus board?
4) After the stop do you still have power into main control board?
5) Have you tried a different computer with all different software?
6) After the stop does Mach3 still respond to all actions normally.
7) Have you checked for loose wires on all circuits that are common to the fault.

The electrical schematic in the manual should be a great help.

Phil

I'm still having major problems. Tormach can't seem to figure it out.

[VaderSpade]

1) Does the spindle stop at the same time as you lose axis control? Most of the time Yes, my main problem has been when returning to zero. The spindle stops just as if it had returned to zero.
Yesterday when I tried to re-reference the mill the Y & Z returned to where they were expected to go but the X was VERY slowly moving the wrong way while emitting a shrill whine.
Other times I get un-expected plunges that break bits and ruin parts.

2) After the stop do all axis still respond to MIDI commands? Yes, when it fails to return to zero, but with a lot of my problems I need to hit the emergency stop.

3) After the stop do you still have power into the bus board? Yes

4) After the stop do you still have power into main control board? Yes

5) Have you tried a different computer with all different software? Yes

6) After the stop does Mach3 still respond to all actions normally. Yes if I did not need to hit the emergency stop.

7) Have you checked for loose wires on all circuits that are common to the fault. Yes, but I plan to go over them again today.

[VaderSpade]

At times the mill thumps and loses steps, a couple days ago while preforming a simple pocketing operation it thumped while moving back to make the ninth of ten passes. It then lost its place and went over an inch past the pocket and then dropped to the depth of the ninth pass and tried cutting that full depth in un-cut material. This broke my bit and ruined the part.
It seems to stall and or thump whenever it gets into a tight corner with quick direction changes. But it’s just as likely to lose its place when traveling in a straight line.

[shred]

Does it ever lose position during actual cutting (G01-2-3, etc), or only during rapids (G00 moves)?
If it fails cutting, is there any chatter when it does? Do you have the PDB or ATC?

[TXFred]

At times the mill thumps and loses steps, a couple days ago while preforming a simple pocketing operation it thumped while moving back to make the ninth of ten passes.

When it thumps like this, does the Computer light go off for a moment? That would indicate a communication failure between PC and mill, possibly due to a loose connection somewhere. You may need to shoot video of the light while you air cut and wait for the thump.

Frederic

[VaderSpade]

When it thumps like this, does the Computer light go off for a moment? No

Does it ever lose position during actual cutting (G01-2-3, etc), or only during rapids (G00 moves)? Mostly during rapids, but it has stalled while cutting, not a full stall just little grunts.

If it fails cutting, is there any chatter when it does? NO I have only been cutting soft (wood and plastic) materials while trying to figure this out.

Do you have the PDB or ATC? NO

[BobWarfield]

My sympathies Vader: diagnosing this stuff drives you nuts. If it's any consolation, when you build your own machine you don't even get to call Tormach for help and there will be more than one problem at least this bad!

People are suggesting all the right things, but just let me hit them again:

- Lost steps due to excess forces somewhere:

o Are you giving it plenty of lube with the one shot? Using real way oil? My mill will servo fault if I don't remember to do this.

o What are chances gibs are too tight or mis-adjusted? Wondering if there is some minor issue with the ways relative to the gibs so the machine is just too tight at certain positions.

o Binding of the leadscrews. Could be due to a lot of things, and you'd think you'd hear that thump more often (each revolution), but I dunno. If the screw isn't mounted quite right, bang.

o Try the suggested slow down trick for a while. Slow the speed a bit, but reducing the acceleration may make more difference. It did for me when tuning.

- Noise:

o Check all the grounds carefully. Look for shorts. Make sure cable grounds are connected at control but not to machine.

- Home Switches:

o Do we know if they're reliable, or if they maybe have some mechanical, electrical, or noise issue?

- Computer:

o Since you got a Tormach PC and assuming you haven't installed anything or adjusted anything, I would think this is good to go. OTOH, if something is marginal, reconfigured, or messed up, Mach is pretty sensitive.

- Warm Up:

o Is it really cold where the machine is? Mine has a noticeably harder time if it is a little cold. Way oil is thicker, yada, yada.
o Consider a warm up program. Write some g-code to move all the axes full travels and run that for 10-15 minutes before starting each day.

- Work around: I can't tell for sure from your description, but it sounded like it mostly works on the first part and fails if you keep making parts. Try re-homing after each part and see if each time you home there are lost steps indicated. Maybe it loses a little on every part and you just don't notice until it gets really severe. For example, lose some steps raising the head each time and that head hangs lower and lower for the cuts. That means the force is going up on each cut. Eventually you start losing steps elsewhere too.

Good Luck!

BW

[VaderSpade]

Well it wasn't the lights, it just thumped and stopped short of zero again.

I did get it on video.

[philbur]

Which axis, how much short? The sound of a stepper motor losing a significant number of steps is unmistakeable, did it lose steps? Put the video on Youtube.

After the "thump" was everything still functioning normally without any resetting or restart etc. If not what was not?

You could also edit your gcode so that the machine loops though the section where problems most occur (while cutting air) without having to wait for it to complete a full run. This would hopefully increase the frequency of failure making it easy to find the fault.

Getting the machine to fault on demand is a good first step toward isolating the fault.

Phil

Well it wasn't the lights, it just thumped and stopped short of zero again.

I did get it on video.

[ImagineRobots]

Well it wasn't the lights, it just thumped and stopped short of zero again.

I did get it on video.

I wonder if this could be an electrical problem. Would it be safe to open up the electrical enclosure and just jiggle any wires that seem like they might be coming loose? Sometimes random problems are the result of an intermittent electrical connection. I don't have a Tormach yet but I did have a bad parallel port connector on my X3 mill conversion board. Just jiggling the connector would cause my Z axis to chatter. I'm sure folks here who have a Tormach could tell you which wires are what. You might also want to jiggle the connections going to the home/limit switches if possible and safe.

[LeeWay]

If it is a loose connection from a drive to motor, the jiggling it could blow a drive. A powered down inspection would be a better choice.

[shred]

Out of curiosity, does your 'return to zero' code move all 3 axis at once? As in G00 X0Y0Z0, or does it move Z first before X and Y?

FWIW, my antique and much-abused 1100 has a problem with poorly-crimped spade lugs in the electrical box. It's not a problem until I go digging around in there, but then they love to pop off at the slightest provocation. It might be worthwhile giving some of the wires a little tug to be sure you didn't get the hung-over wire-crimper-guy too.

[pete from TN]

But from listening to your issues and since it is NOT apparently from a single axis I gotta say that I have had terrible issues at one point with my RF45 CNC conversion that I tore my hair out trying to find. Ultimately it turned out to be the control computer that was causing all of the problems. I replaced the computer and it worked WAY better and the problems went away. From the sounds of what you are describing you have either a computer control issue, noise in the system, or you have some major binding issues. I would think that would probably NOT be the case since you say it is very random and not on the same axis every time. I would be very tempted to swap out the computer and get into the cabinet and check all the connections for a short or loose connection. Again since it is not always on the same axis this kinda narrows things down a bit for you. Sorry you are having all the problems. Good luck and post that damn video maybe one of these guys has been there and can see what you are having going on. Sometimes another pair of eyes can see something you cannot. Peace

Pete

[ImagineRobots]

If it is a loose connection from a drive to motor, the jiggling it could blow a drive. A powered down inspection would be a better choice.

My guess is that it's not the power connections going to the motors since the missed steps have occurred on more than one axis. Also, I'm thinking it's not the limit switches because in Mach 3 hitting a limit switch (or flakey switch) would require the operator to then press the screen RESET button to continue operation (if set up that way). It does make sense to not jiggle the motor power wires but signal wires are probably ok. The parallel port connector/cable would be easy to jiggle. It's disturbing that one of the axis during homing moved in the wrong direction. What could cause this other than a flakey direction signal? What does Tormach say?

If the signals are ok then maybe check the power. Based on the thread, I'm noticing that the problems occur when there is a lot of load on the stepper motors (rapid moves, change in direction) - almost like it's a power supply issue going to the motor drivers. Perhaps ask Tormach how to check the power supply. Also, what are the AC mains & circuit breaker requirements going to the Tormach? An overloaded circuit breaker in your house panel will often buzz if it's on the very edge of tripping.

[VaderSpade]

Thanks for all the help and keep the suggestions coming. I plan on wring the mill into a different drop from a different transformer as soon as I can find the time (but before I run it again) hopefully later today but I have work to do in my neglected lapidary business.

I have tried almost everything that has been suggested in the posts up to this point. I’ll try and get that video up but it’s been a few years since I posted a video and I know it will take time I don’t have right now. But soon.
Thanks again for all the help everyone.

[ImagineRobots]

Thanks for all the help and keep the suggestions coming. I plan on wring the mill into a different drop from a different transformer as soon as I can find the time (but before I run it again) hopefully later today but I have work to do in my neglected lapidary business.

I have tried almost everything that has been suggested in the posts up to this point. I’ll try and get that video up but it’s been a few years since I posted a video and I know it will take time I don’t have right now. But soon.
Thanks again for all the help everyone.

Are you using an external step up transformer to go from 120VAC to 240VAC?