I could use some help
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@mac said in I could use some help:
@fcwilt right now the y's at 0.0. My ruler's telling me the bed's at 9 and 5/8th inches forwards of HOME. What would G1 H1 Y-244 F3600 do? (Currently, in homey.g) the command is G1 H1 Y-360 F3600.
In relative mode (G91) a G1 H1 Y-244 command would move until the endstop triggered OR until the move has covered the distance specified, in this case by the Y parameter of 244mm.
If you did G91 then G1 H1 Y-10 it would only move 10mm "looking" for the endstop to trigger.
So normally the first G1 H1 move in the homing code specifies a distance to be sure the move covers the entire length of the axis while "looking" for the endstop to trigger.
The Y-360 is 10mm more than the distance of 350 that you determined to be the max travel on the Y axis.
Frederick
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@mac said in I could use some help:
@fcwilt In the Status Display, Y is at 0.0. It's already "Home." It can't go into negative territory.
Since G1 H1 moves are intended to be used to home and homing is done with the assumption that the actual positions of the axes are unknown, the G1 H1 moves ignore the M208 limits and try to move the specified amount.
This can mean if the move is away from the endstop or the endstop is not working the move can encounter the end of travel but keep right on trying to complete the move.
Frederick
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@fcwilt I homed again, it went forwards again, and smashed into the adjustment cap again.
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@fcwilt what if I change the Y-360 to Y 360?
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What if I change the code to what's below?
G1 H1 Y 360 F3600 G1 Y15 G1 H1 Y=10 F360 G90 G1 Y110 F3600 -
@mac said in I could use some help:
@fcwilt I homed again, it went forwards again, and smashed into the adjustment cap again.
This makes no sense at all.
OK here is a thought. Perhaps the forwards move is the G1 Y110 at the end of the file.
So lets try this:
- jog the bed back to somewhere in the middle of it's travel
- execute a G91
- execute a G1 H1 Y-10 which should be a 10mm move. It's not far enough to smack into anything but it will tell us in what direction the G1 H1 Y-10 command moves the bed.
Thanks.
Frederick
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@mac said in I could use some help:
What if I change the code to what's below?
G1 H1 Y 360 F3600 G1 Y15 G1 H1 Y=10 F360 G90 G1 Y110 F3600You are faster than me. I just posted a little test to verify if the G1 H1 move is actually going in the correct direction.
Frederick
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@fcwilt G1 H1 Y-10 moved the bed 10mm towards the END STOP!
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@fcwilt Interestingly, Y is saying 0.0
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@fcwilt I did it again, now Y's saying -10
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@fcwilt I changed the end to Y-20. The bed went towards the rear 20mm. Y is reporting -30mm.
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@fcwilt according to my measurements, and my inches to millimeter calculator, if I change the number to Y-92.075mm, the foot of the bed will touch the end-stop.
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@fcwilt hmmmm, the bed's being weird. I'm sending G1 H1 Y-92 , but the bed is inching towards the end stop instead of going straight for it.
And Y is now 0.0 again, whereas it was -30.
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@fcwilt okay, I've gone back to telling the board to move the bed back 10mm at a time (Y-10). It's working again. Y is at -10.0. It's also (I jogged it twice more), about 5mm from the end stop now.
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@fcwilt I've moved the bed back to the center of the 452mm's. That's 9 inches (of 18). Y is reporting 100.00 now.
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@fcwilt I have to run an errand. I'll be back in an hour.
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@mac said in I could use some help:
@fcwilt hmmmm, the bed's being weird. I'm sending G1 H1 Y-92 , but the bed is inching towards the end stop instead of going straight for it.
And Y is now 0.0 again, whereas it was -30.
The change to Y=0 should be because the endstop was triggered.
The post move behavior of a G1 H1 move is to set the axis position to the min or max value specified in the M208 for that axis.
Since the endstop for this axis is specified to be at the low end, the min value is used, and that is just what you are seeing.
Was the move, while slow, smooth and even?
It could because you did not specify an F parameter for the move. In that case it uses the speed set by the last F parameter that was executed.
You could try it all again but this time include, say, F3600 in the G1 H1 moves.
Frederick
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@mac said in I could use some help:
@fcwilt I have to run an errand. I'll be back in an hour.
Sounds good. I have a chore to do as well.
Be safe.
Frederick
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@fcwilt
I've got to hand it to you, Frederick. You have tha patience of Job.
