Tool Change

[LGreen]

After a tool change is entered thru MDI (i.e. T1M6) cycle start remains inactive. Thus I cannot measure any tools in MTM. Any thoughts?

[DaveCVI]

Hi,
That fits the symptom of a known brains bug in mach. See the MSM release notes, item 4.1 for the way to correct it.
Dave

[LGreen]

Thank you, problem solved. I've got to say I love the title of that paragraph. I am 68, still waiting.

[LGreen]

A new dimension to this problem. Activating the brain solved the button problem and for a few cycles everything worked well, then the Z feed rate slowed to the point that Z would move about .5 inch then stop with a message that the TP was not found then abort. I Shut down mach, restarted the computer, tried again. Now Z ramps up to the normal feed rate, moves down, contacts the TP, then ramps to a stop driving the tool into the TP in the process. My touch plate now looks like a target at the pistol range. I have checked the ground circuits, they are good, tested with a jumper wire, the touch plate response is instantaneous. A touch to the tip of the tool is likewise. Any thought on this?

[ChrisAttebery]

This sounds a lot like the problem I'm having with my machine.

[LGreen]

Chris, I've got hope that this problem will get solved. Stay tuned.

[DaveCVI]

Hi,

A new dimension to this problem. Activating the brain solved the button problem and for a few cycles everything worked well, then the Z feed rate slowed to the point that Z would move about .5 inch then stop with a message that the TP was not found then abort. I Shut down mach, restarted the computer, tried again. Now Z ramps up to the normal feed rate, moves down, contacts the TP, then ramps to a stop driving the tool into the TP in the process. My touch plate now looks like a target at the pistol range. I have checked the ground circuits, they are good, tested with a jumper wire, the touch plate response is instantaneous. A touch to the tip of the tool is likewise. Any thought on this?

Is this a parallel port system or something else?

The fact that a restart changes the symptom significantly is worrisome. I don't know of a mach bug that fits that symptom.

Are the acceleration values for the Z axis set really low? That's the only thing I can think of that would let the tool keep going once the plate is triggered.

If the plate were NOT triggering, you could drive it past the plate... is there continuity from a tool tip to the machine frame (i.e. via the tool holder then spindle etc)?

Dave

[LGreen]

Thanks for responding, yes this is a parallel port system. The Z Acceleration is set as high as I can possibly set it so that the stop is almost instantaneous, that's not a problem because this is on a lead screw (1 start) the IPM is 50. I have lowered it as much as 20,there is overrun at any speed, just the slower the speed the less the overrun. The plate is triggering instantly on contact and the measurement is accurate. There is continuity to the frame from tool and any other metal part on the router to the frame. The overrun is enough that it racks the gantry and causes the X axis motors to turn and lose position (chain drive). Mach3 is the current release .066 MSM is also the latest. What puzzles me most is that it would change to this after a few cycles of performing correctly. I most certainly don't have the best system in the world as it is Homebuilt, but it is what I have. Along with that I am certainly no expert, as I've never tried anything like this before and I'm quite out of my depth, but I am working very hard to get up to speed. My confession, now your thoughts?

[LGreen]

Just for clarification, the overrun is only in the tool measurement operation

[DaveCVI]

Hum,
We know that the probe input is triggering. If it were not being triggered, there would be no deceleration at all.
I don't know of anything that will cause mach to change decelleration rates like that. I've never had a system change rates between runs.
These are long shot guesses on my part:
1) anything else running on the PC that could be stealing the CPU from mach?
2) Are there any poser saving "featues" turned on in the PC that could be dynamically impacting CPU clock speed etc?

Dave