Can't set endstop?

[Zackett]

I recently got into 3d printing and bought myself a printrbot play. Today I was having connectivity issues so I resorted to having to flash the firmware and reinstall it (updated it while I was at it) and it prints well again. Problem is that when I use the pronterface UI on cura and click on the manual axis arrows my printer won't hesitate to try to go outside it's range and will start grinding on any axis. My printer never used to do this. I'm no expert but I've read that I need to change the "soft limits" I'm the firmware. And I cant for the life of me figure out how I can do that? I can't find a tutorial on doing that anywhere. Help??

[Zackett]

Help anyone? I respons relatively soon would be appreciated

[RetireeJay]

[Mooselake]

[Zackett]

[RetireeJay]

The Marlin firmware, by default, ONLY pays attention to the "endstop" switches when executing a homing maneuver. At all other times, the "endstop" switches are IGNORED. And there's only one "endstop" switch per axis, so even if the switches were not being ignored you could still exceed the physical limits of travel in the other direction and get the motor grinding like you say.

It is possible, if you really want to try it, to compile the firmware with the "endstop" switches enabled all the time - but it's a whole lot harder to configure a version of Marlin from the source code than to just download a pre-compiled hex file, and that still doesn't fix the problem on the other end of each axis.

So, back to basics: yes, there are settings you need to update; that's really pretty common and should be expected. If you are willing to work with us just a little more, issue an M503 command and copy and paste the entire list of parameters so we can see if something jumps out at us.

See my first post (before Mooselake's); I think I did answer your quest for info on the "soft limits;" I'm sorry if it wasn't clear enough that I was referring to the same thing you were referring to. Although I can see now that I should have pointed you to the first post in the chain about setting the software limits of travel: viewtopic.php?f=15&t=10876 (All generations of Printrbots have used fundamentally very closely-related hardware and software so in most cases guidelines for the "Plus" apply equally to the "Simple" or the "Play.")

[Zackett]

That answers a lot of my questions, thank you. I didnt know that default settings ignored the endstop. And of course, here is my settings on cura

> M503
< echo:Steps per unit:
< echo: M92 X80.00 Y80.00 Z2020.00 E96.00
< echo:Maximum feedrates (mm/s):
< echo: M203 X125.00 Y125.00 Z5.00 E14.00
< echo:Maximum Acceleration (mm/s2):
< echo: M201 X2000 Y2000 Z30 E10000
< echo:Acceleration: S=acceleration, T=retract acceleration
< echo: M204 S3000.00 T3000.00
< echo:Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s), Z=maximum Z jerk (mm/s), E=maximum E jerk (mm/s)
< echo: M205 S0.00 T0.00 B20000 X20.00 Z0.40 E5.00
< echo:Home offset (mm):
< echo: M206 X0.00 Y0.00 Z0.00
< echo:PID settings:
< echo: M301 P22.20 I1.08 D114.00
< echo:Min position (mm):
< echo: M210 X0.00 Y0.00 Z0.00
< echo:Max position (mm):
< echo: M211 X100.00 Y100.00 Z131.00
< echo:Bed probe offset (mm):
< echo: M212 X5.00 Y0.00 Z-0.65

[RetireeJay]

[Zackett]

So your saying that the pronterface will always cause grinding if i use the arrows?
Also, i change my x and y axis limits with the M212 command right?

[RetireeJay]

[Zackett]

I typed the command you made in and saved it, i double checked it as well. Despite homing the printer i can still use the arrow keys to go beyond the limits and grind the motor. I even changed X 50 Y 50 and saved the command. The printer will home to a much smaller area on the bed, but after that i can simple press the x arrow and go beyond the limits and grind the motor again..

[RetireeJay]

Ouch. That's surprising and disappointing. All I can say is that some option in your firmware is set up differently.

In addition to setting the bed size in firmware (i.e. on the Printrboard's EEPROM), you should also set it in Cura (or Repetier + Slic3r). In Cura, the bed size is defined under "Machine" -> "Machine Settings." If you use Repetier and Slic3r instead of Cura, then you can set the bed size BOTH in Repetier AND in Slic3r. When all programs are using the same settings, you shouldn't have the problem. I always recommend entering the same settings in every place that they are available.

Anyway, if the objects you are printing don't exceed the bed size, and if they are properly centered by your slicer, then you should not have a problem with the printer exceeding its physical limits while doing a print.

[Zackett]

I use cura, which of course sets the bed size correctly when you choose the printer you are using. Like i said before, i used the printer once since i flashed the firmware and it worked fine, i figured cura wouldnt let my printer go beyond the bed size limits. It just disturbs me that i can force the machine to go beyond its limits when i never was able to before. Perhaps the updated firmware i got from printrbot is set up different than what it used to be?

Anyways, i guess i theres no fix for this unless printrbot makes another update. I really appreciate your help and quick responses. Have a happy and safe 4th of July!

[RetireeJay]

Just FYI...
The only "sensors" of any type on the printer to tell it where it is are the "endstops" and Z "probe." In other words, once the printer has been homed, it keeps track of its position "open loop" relying on the (excellent) reliability of the stepper motors, and keeping track of how many steps forward or back have been issued to know where it is. Why does this matter? Two things: (1) It means that when you accidentally tell the printer to go 10mm beyond the end of the X axis, it's not going to keep trying to go to 110mm forever. It will issue the correct number of steps to get to 110mm and then stop. As far as the motor is concerned, it has only "hopped" between magnetic poles; nothing mechanical inside the motor is getting worn or damaged. So you don't need to panic and pull the plug. In fact, pulling the plug has a much higher risk of doing permanent damage than just letting the machine sit there and grind for a while. Although you don't want to make a habit of it, because it's hard on the belts and some other parts! (2) It means that when your machine does encounter an obstacle (either an end of travel on the axis or something else blocking its motion) then the actual position no longer corresponds with the theoretical position in the firmware. After such an incident, you need to re-home.

The exception to the memorized position based on counts is when doing a homing maneuver. In that case, the machine is moving toward the "endstop" switch and will keep on moving until the endstop is reached; it's not counting steps. So in that case, an axis whose motion is blocked will grind "forever" and you really do need to pull the plug or, preferably if you can do it, hit the little reset switch on the board.

Even if your motion limits are working correctly and the machine stops at the end of an axis without grinding, it can still get confused on the counts, so exceeding the bed size is never a good thing to do.