[Rooski]

I have seen some reference to homing in a few threads, but I have a question I haven't seen the answer for yet.

I have my slow zone speeds set to 5%, 5% on X and Y axes. While referencing home, the speed is nice and slow, as are my slow zones for soft limits.

What about after the machine coordinates are already setup and the GOTO Home button is pressed. The machine races to the home switches at full speed (409"/m) and slams to a stop. It does not hit a hard stop or the switches themselves. It comes to 4mm away from the switch as it should. (the switches are magnetic I believe).
Once stopped, the limit switch lights are on red (cable end of switches have led's) and I have to reset from a tripped limit. That means I need to manually push the gantry and Z plate away from my X and Y home switches in order to reset.

Debounce set at 2000 in gen config.

Is it supposed to do this? Being the user is asking the unit to go home, maybe it is (??) Am I just missing something really simple here?


Thoughts?

[ger21]

Are you pressing the goto ZERO button? That's not going to send it home.

On either the Settings or Diagnostic page is both an auto limit override and a manual limit override. Both will allow you to reset and jog off the switches.

[Rooski]

Ok, got it.
It was my X (and A slaved) that were hitting limit on GOTO Zero.

I see now that my work offset setting had my X at the same zero point as where I home the machine coordinates.

I would really only need to goto zero for a work offset anyway it appears.

I reset the slow zone and although it is still at 2", seems just going through that motion has now stopped at 2" where it was stopping at just shy of a 1/4" before.


Maybe a silly question regardless of need, but is reference home the only way to bring back to the machine zero coordinates? (other than if I had an identical offset set this way)



Thank you

- - - Updated - - -

Also turned on the auto limit override. Works great !

[ger21]

Yes, Ref Home is the ONLY way to reset machine coordinates. You should do it each time you start your machine.

What is your Softlimit Minimum set to?

[mmoe]

If you are using the limit switches to set home, then the problem is anytime you go to machine zero, you'll end up on the switches. You can set the home position to be something other than 0,0,0 so that the machine coordinates are, say, X= -.5", Y= -.5" and Z= .25" or whatever you prefer. That way, when you go to machine zero, you won't trip the limit switches. In the "Config" menu you would go to Homing/Limits window, then put those values (or whatever your preference is) into the "Home Off" setting. Keep in mind that this setting is what you are saying that position actually is, so if you tell it that the position is -.25", then it will move back .25" to 0 after it hits the switch. If you put .25 in that setting, it will move further toward the limit switch, so be careful with that setting and think it through.

If you want the motors to come to a stop slightly more gradually, you can set the acceleration setting in motor tuning a little lower. If it's jerky when stopping, that probably wouldn't be a bad idea.