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Still calibrating

Hey gang!
I’m still working on calibration. Here is another problem I’ve been seeing since the last seems to be resolved for the most part.

I am trying to get Z-axis dialed in. When I click “Move Down,” my left X/Y motor starts turning clockwise.

The last attempt at calibration yielded a similar problem. I actually had Z-axis dialed in to 10.31mm on expected movement of 10mm. I was fairly content with that so, per instructions, I lowered the bit to just barely contacting the waste board and set Zero. Afterwards, I pressed “Home,” and the X/Y motors began lowering the sled so I clicked “Reset,” before it dumped the sled off the frame. It has done that since the first run so, this time I unchained the sled and placed it on a table to zero out Z-axis.

What, on earth, is going on with it? As always, I greatly appreciate this community and the support.

I think this is probably an issue with the machine not knowing it’s chain lengths. I would try to do the set chain lengths operation to get them back to a known length.

Thank you! I’ll go through my settings again and try to find that. Again, I appreciate the input. I’ve worked with industrial cnc routers before but this is a little different so I am still learning a lot :joy:

setting the chain length is not a one time thing

When the system forgets where it is (because you hit reset/powered it off in the
middle of movement, etc) it has no idea where it is and no way to sense it.

This system does not have an ability to home to switches like the CNC machines
you are used to (if it doesn’t know where it is, it can’t know if it’s safe to
extend, retract, or do nothing with one motor while it tries to retract the
other motor to reach a limit switch)

so after it loses it’s position, you have to either go through calibration
again, or (if you marked you chains when you went through calibration), you can
reset to a known position, tell the machine you have done so, and then start
again.

David Lang

Ahhhhh ok. That makes sense. So it really can’t save home position to be used as a restart point. So, I probably need to manually reset the chains and complete the calibration. Then I will need to do that each time I actually run a program, or at least click to set chain position right?

The machine is basically counting rotations=chain distance with no way of verifying that it is correct.

So, just thinking ahead, before running, if I manually move to (0,0) and click “set chains,” that should get me off and running if that reflects what my calibration is understanding to be home position?

when the machine is running normally, after about 2 seconds of inactivity it
saves it’s positions and shuts the motors off (they stop buzing), at that point
it will remember where it is.

the saved position is not neccessarily 0,0, it’s where the chains have fed out a
known amount of chain (by default with stock firmware 1651mm), during
calibration, you load the chains, it feeds out this known amount on each side
and tells you to hook up the sled. This is the point where you mark the link on
the chains that is on the 12 o’clock tooth of the sprockets. You then ‘move to
home’ where it moves to 0,0

when you have to reset the chains, you adjust the sprockets to they have a tooth
(any tooth) at 12 o’clock, put the marked links on that tooth, and tell the
machine to reset the chain lengths to this known state.

David Lang

Thanks for breaking it down. You did a far better job explaining it than the included instructions :rofl:

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