Z axis troubleshooting

[ecdez]

Tormach 1100 series 3 - bought around 1/15



Today, while cutting a pocket the z axis decides to plunge about 1/2" unexpectedly. Thought it was a fluke so I loaded another blank. Did it again in a different spot.

Decided to restart the program and let it run just to see what would happen. The last time I ran it, it finished the pocket without incident but didn't pickup to go to the next pocket; it just plowed through the part.

Each time, the DRO did not match the movement. When it plunged the DRO showed the correct depth. When it plowed through the wall it showed the Z axis moving.

The pocket is the 5th action in the program. Predrill about 20 holes, drill those same holes, rough two edges (multiple depths), rough a hole in the middle (multiple depths), THEN the pocket. I just let the part finish anyway and everything was fine; chamfering, backside chamfering, tapping holes. The pocket is the only operation where the Z axis stays at the same depth for any length of time.

This is a part I've made several times with no problems so confident it's not the program.


I called the Tormach tech support line and I'm waiting to hear back so I thought I'd pose the question here too.


Any thoughts.

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[nitewatchman]

I have had this type random Z Axis failure also. Mine turned out to be the Z Axis motor driver or more correctly the motor connector on the board. In my experience the power connectors on the drive are prone to overheat and oxidize or burn. This can be easily seen by pulling the connector and looking at the pins.

If it is not badly burned removing and reseating the connector several times which wipes the contacts restoring continuity. If the contacts are badly burned and the plug melted the issue will worsen until there is a complete failure. Frequently pulling the plugs will help.

I have gone through three drives in the last 6 or so years.

gary

Tormach 1100 series 3 - bought around 1/15



Today, while cutting a pocket the z axis decides to plunge about 1/2" unexpectedly. Thought it was a fluke so I loaded another blank. Did it again in a different spot.

Decided to restart the program and let it run just to see what would happen. The last time I ran it, it finished the pocket without incident but didn't pickup to go to the next pocket; it just plowed through the part.

Each time, the DRO did not match the movement. When it plunged the DRO showed the correct depth. When it plowed through the wall it showed the Z axis moving.

The pocket is the 5th action in the program. Predrill about 20 holes, drill those same holes, rough two edges (multiple depths), rough a hole in the middle (multiple depths), THEN the pocket. I just let the part finish anyway and everything was fine; chamfering, backside chamfering, tapping holes. The pocket is the only operation where the Z axis stays at the same depth for any length of time.

This is a part I've made several times with no problems so confident it's not the program.


I called the Tormach tech support line and I'm waiting to hear back so I thought I'd pose the question here too.


Any thoughts.

[ecdez]

I have had this type random Z Axis failure also. Mine turned out to be the Z Axis motor driver or more correctly the motor connector on the board. In my experience the power connectors on the drive are prone to overheat and oxidize or burn. This can be easily seen by pulling the connector and looking at the pins.

If it is not badly burned removing and reseating the connector several times which wipes the contacts restoring continuity. If the contacts are badly burned and the plug melted the issue will worsen until there is a complete failure. Frequently pulling the plugs will help.

I have gone through three drives in the last 6 or so years.

gary

That's exactly why I posted the question here; practical experience Initially I thought it was the z axis brake but that would not have caused it to not lift when it was supposed to. Then I started thinking the driver. I'll be checking those connections later today!

I still hope to hear from tech support but this give me a direction to start looking.

Thanks!!

[popspipes]

Tormach 1100 series 3 - bought around 1/15



Today, while cutting a pocket the z axis decides to plunge about 1/2" unexpectedly. Thought it was a fluke so I loaded another blank. Did it again in a different spot.

Decided to restart the program and let it run just to see what would happen. The last time I ran it, it finished the pocket without incident but didn't pickup to go to the next pocket; it just plowed through the part.

Each time, the DRO did not match the movement. When it plunged the DRO showed the correct depth. When it plowed through the wall it showed the Z axis moving.

The pocket is the 5th action in the program. Predrill about 20 holes, drill those same holes, rough two edges (multiple depths), rough a hole in the middle (multiple depths), THEN the pocket. I just let the part finish anyway and everything was fine; chamfering, backside chamfering, tapping holes. The pocket is the only operation where the Z axis stays at the same depth for any length of time.

This is a part I've made several times with no problems so confident it's not the program.


I called the Tormach tech support line and I'm waiting to hear back so I thought I'd pose the question here too.


Any thoughts.

As Gary said check the driver connectors, I made a post with pictures about a year or so ago showing my problem, all 3 axis driver connectors failed at different points in time on my 1100. The connector is just too small for the current it has to carry.