Printrbot 1405 Z motor not working

Need help troubleshooting hardware issues... talk here

Printrbot 1405 Z motor not working

Postby snatchesandsubarus » 2017-Jan-Wed-09-Jan

Hey guys,

I acquired a simple makers kit about a month ago so I am still a noob. I have upgraded it with longer rods all around and a little bit larger bed. Everything has been working for a couple weeks now until I ran a simple print job to make some legs to prevent the printer from tipping over. It seemed as the one of the axis was off a little so I stopped the print job halfway through and checked all the settings. Nothing had changed from the print job I completed minutes before. I cleaned everything off and started the print job again. During the calibration test before the job started the Z motor seemed to be not moving at all.

I took everything apart and tested everything and it seems like the Z axis connection on the board went bad, is that possible? I connected the Z motor to one of the other motor connections on the board and it moved normally. Then connected the other motor to the Z motor connection and that one didn't work.

Could this be something software/firmware related or am I stuck having to replace the board? I am just a little confused because during the last print job the Z motor seemed to be working just a little off which lead me to believe the motor was going bad...

--Ryan--
  • 0

snatchesandsubarus
Waiting to connect to printer...
 
Posts: 7
Joined: 2017-Jan-Wed-08-Jan
Reputation: 0

Printrbot 1405 Z motor not working

Sponsor

Sponsor
 

Re: Printrbot 1405 Z motor not working

Postby RetireeJay » 2017-Jan-Wed-10-Jan

Well, your tests show that the problem is not in the motor itself but on the Printrboard.

When you "stopped the print halfway through" how did you stop it? Did you simply cut off the power, or did you use the Reset button on the board, or some other technique? If you simply cut off the power, it's possible that there was a "glitch" caused by stored energy in the motor coming back into the board. The motor-driver chips are pretty robust, but it's possible for them to be damaged (which would entail replacing the chip on the board or replacing the whole board). Perhaps more likely, though, is a disturbance to the firmware. If you're lucky, it's in the EEPROM. So issue an M503 command and look for the calibration line for the X, Y, Z, and E axes in steps per mm. The correct value for Z steps per mm depends on your particular Z actuation screw, but it's typically somewhere near 2000 give or take 500 or so. If yours has gone to zero, or a small value, then try issuing an M502 command, which will reset the EEPROM values to "factory default."

As a last resort, if this doesn't fix it, you could try re-flashing your firmware. Doing so is rarely needed, but it's free and does sometimes solve some problems. However, re-flashing can also introduce new problems if you don't use the right version, so beware.
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
User avatar
RetireeJay
My next printer is...
 
Posts: 4629
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 476

Re: Printrbot 1405 Z motor not working

Postby snatchesandsubarus » 2017-Jan-Wed-11-Jan

I stopped the print using the "kill" button in Repetier.

When I checked last night all of the settings seemed to be where I previously set them but it was late so they may have been off. I will re-check when I get home tonight and if they have not changed I will try resetting the EEPROM like you said.

Thanks
  • 0

snatchesandsubarus
Waiting to connect to printer...
 
Posts: 7
Joined: 2017-Jan-Wed-08-Jan
Reputation: 0

Re: Printrbot 1405 Z motor not working

Postby RetireeJay » 2017-Jan-Wed-13-Jan

Using the "kill" button in Repetier is definitely a safe, good way to stop a print. That would NOT cause any "glitch". It won't hurt to check the EEPROM settings.

You've already proven that the motor itself and the wiring from the board to the motor is good, and the output from the board on the Z channel is not, so now what we suspect is the driver chip.

Do you have a multimeter? With power off, you could compare the ohms you see between pairs of pins on the Z connector versus pairs of pins on another motor's connector. The driver chip uses the two pins on one end of the connector to drive one coil in the motor, and the two pins on the other end of the connector to drive the other coil. Check the readings in both directions (let's call them forward and reverse). So you end up with a total of 4 readings from the Z connection and 4 more readings from the other motor's connection. Comparing apples to apples, the readings should match up (Z1-2Forward ~= X1-2Forward and so on). If you see a dead short or an open circuit, then we have a starting point for electronic circuit debugging. (By the way, schematics are at [url]reprap.org/wiki/printrboard[/url]).

It might help to be more specific and detailed about what was going wrong that prompted you to kill the print.

Worst case, maybe the board has gone bad. My original board went bad after about three years. It would sorta respond to commands, but not execute them fully or correctly. When I tried to re-flash the firmware, it was then totally bricked.
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
User avatar
RetireeJay
My next printer is...
 
Posts: 4629
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 476

Re: Printrbot 1405 Z motor not working

Postby snatchesandsubarus » 2017-Jan-Thu-19-Jan

Ok here is all of my testing results so far

RetireeJay wrote:So issue an M503 command and look for the calibration line for the X, Y, Z, and E axes in steps per mm. The correct value for Z steps per mm depends on your particular Z actuation screw, but it's typically somewhere near 2000 give or take 500 or so. If yours has gone to zero, or a small value, then try issuing an M502 command, which will reset the EEPROM values to "factory default."


I issued the M503 command and nothing happened.. I issued the M501 command and was able to see the steps per mm in those results and they are what I had sent them to previously (after calculating for upgraded acme screw). I also issued the M502 command which successfully reset the EEPROM.

RetireeJay wrote:As a last resort, if this doesn't fix it, you could try re-flashing your firmware. Doing so is rarely needed, but it's free and does sometimes solve some problems. However, re-flashing can also introduce new problems if you don't use the right version, so beware.


I believe I flashed the board because I followed all of the steps and the program finished with a "successful" but the firmware name is the same. I completely forgot to check the version before I flashed it but I am almost positive it is the same.

RetireeJay wrote:Do you have a multimeter? With power off, you could compare the ohms you see between pairs of pins on the Z connector versus pairs of pins on another motor's connector. The driver chip uses the two pins on one end of the connector to drive one coil in the motor, and the two pins on the other end of the connector to drive the other coil. Check the readings in both directions (let's call them forward and reverse).


I do have a multimeter... here are the results, I hope I did it correctly lol
ohm test.PNG


RetireeJay wrote:It might help to be more specific and detailed about what was going wrong that prompted you to kill the print.


This is the print I killed halfway through. I watched the first layer or two and everything looked fine and came back a little while later to this(and seemed to be getting worse)...
WIN_20170105_18_29_29_Pro.jpg

WIN_20170105_18_29_45_Pro.jpg



Thanks!!
  • 0

snatchesandsubarus
Waiting to connect to printer...
 
Posts: 7
Joined: 2017-Jan-Wed-08-Jan
Reputation: 0

Re: Printrbot 1405 Z motor not working

Postby RetireeJay » 2017-Jan-Thu-20-Jan

Were you measuring volts or ohms? The little "v" beside the numbers makes me think you measured volts.

But in any event, although the numbers for Z are slightly lower than the numbers on the other channels, the difference is not significant enough to explain your total loss of Z actuation. It's possible that your board has a hardware defect, meaning a break in the conductor between the Atmel chip and the Z stepper driver chip, so that the commands to perform steps are not arriving at the driver chip. Since you found the board layout, I presume you can also find the board schematic and figure out which pins are involved; then you could check the resistance between the driver chip "step" input and the corresponding Atmel output pin to see if it's zero.

When you re-flash your firmware, it's normal for the name to stay the same; you replaced a possibly defective copy with a good copy of the same firmware. (And incidentally updating the name of the firmware is often forgotten by the programmers, who are so excited that they have a new working version of the firmware complete.)

It's curious that the bottom of the print on the right (the one with the strings) looks much more "porous" than the print on the left. Were you printing both of them at the same time?
  • 0

Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
User avatar
RetireeJay
My next printer is...
 
Posts: 4629
Joined: 2013-Jan-Wed-13-Jan
Location: Greenville, SC
Reputation: 476

Re: Printrbot 1405 Z motor not working

Postby snatchesandsubarus » 2017-Jan-Thu-20-Jan

RetireeJay wrote:Were you measuring volts or ohms? The little "v" beside the numbers makes me think you measured volts.

But in any event, although the numbers for Z are slightly lower than the numbers on the other channels, the difference is not significant enough to explain your total loss of Z actuation. It's possible that your board has a hardware defect, meaning a break in the conductor between the Atmel chip and the Z stepper driver chip, so that the commands to perform steps are not arriving at the driver chip. Since you found the board layout, I presume you can also find the board schematic and figure out which pins are involved; then you could check the resistance between the driver chip "step" input and the corresponding Atmel output pin to see if it's zero.


I knew there was something off, I had to dust of this multimeter which also means remembering how to use it. I retested measuring ohms and got
Z pair 1 - 26.29M Ohms
Pair 2 - 26.42M Ohms
Y Pair 1 - 31.20M Ohms
Pair 2 - 30.71M Ohms

I will see if i can dig a little deeper with testing now...

RetireeJay wrote:It's curious that the bottom of the print on the right (the one with the strings) looks much more "porous" than the print on the left. Were you printing both of them at the same time?


Yes, these were printing right next to each other
  • 0

snatchesandsubarus
Waiting to connect to printer...
 
Posts: 7
Joined: 2017-Jan-Wed-08-Jan
Reputation: 0


Return to Troubleshooting talk

Who is online

Users browsing this forum: No registered users and 2 guests