Hey guys. So I come to you again with yet another question. I came home from work today to find ANOTHER one of my prints gone haywire. I swear if I watch this thing the print comes out perfect, but if I leave even to go to the bathroom it screws up. And then it comes to ME with trust issues like I’m the problem, how can I leave it over night if I cant have it going solid for more than one print in a row. this started to happen a month ago, and ever since every few prints on messes up. I bed lvl it every print, tighten the belts tighten the motor pulleys, lub the rails, I DO EVERYTHING! is their something I’m missing.
PS: it usually messes up in a may like it skipped on the x axis, or heavily screwed up on the z axis and goes plowing though the started print. the y axis seems to be fine never messed up there. but the thing is is that I’m printing very slow even for this printer, 20mm/s bed at 60 and hotend at 195, fan always on. HELP ME!!!
Your jerk settings probably need to be changed if it’s missing steps. Or you could upgrade the stepper motors, but I think the printrbot has decent ones.
If your belts are too tight or extruder idler is too tight, you will have issues.
Also check the drive gear of the extruder, sometimes if it grinds filament it clogs the drive gear, you need to clean it (i use a needle and a lot of patience).
You need to be a little more descriptive than haywire.
20 mm/s and still having problems? I run the PrintrBot at 60 mm/s and it’s perfect.
Hard to say what exactly could be the problem if you’re never there to see it and watch what is actually occuring. Don’t suppose you could set a camera up on it while it’s printing?
@Tom_Nardi ya I’m going to do that. see what I come up with. just curious what are your settings for the printrbot, cause when I ran my at 60mm/s it was skipping all over the place.
@Stephanie_A Thanks for the info, down near the end of the paragraph I do give as much of a detail synopsis of what’s wrong, but what is the best tension for the belt, and how can I tell. also u mentioned jerk settings, how do I adjust those?
My Printrbot Simple Metal zips along at 80mm/s, making beautiful prints, so needing to slow down to 20 would be extraordinary.
Yours has the heated bed option, but mine still has the original cold bed, so you you must have a new power supply to deliver extra current to the bed.
Here is a conjecture: maybe the new power supply is flakey.
To test, could you print something narrow and tall without using the bed heater or fan, and see if you can at least reach 60mm/s without issues?
What I am looking for is: will your power supply work well without an inductive load like a fan, plus only a fairly small current demand.
You could even switch back to the original supply as part of this test.
Honestly, I would be very interested to know why you cannot print faster than 20mm/s as a priority.
@Paul_Gross the thing is, is that when I print fast even when the heated bed wasn’t on(I’ve had this issue for a while) printing above 50mm/s was risky giving me prints that were cut in half and slightly shifted along the x axis. By the way the fan is the same fan that comes with it to cool the hot end tip and the print. My belts are pretty tense and the motor pulleys are tightened fast. Not sure where the ship happening but it only happens on the x axis. The z axis very rarely fails only noticed it today as I seemingly plowed through my print, I say seemingly because I want there to watch it and my dad caught it and cut the power b4 any damage was done.
The z axis hardly fails, so that is a definite sign. I’ve seen strange issues where the printrboard goes bad, so it’s a possibility. You can try reflashing the firmware and see if that helps.
The belts should not be overly tight, I’m able to pluck mine to a very low tune. Also check pulley alignment, I’ve seen in the past where side of the belt can rub, inspect the belt for signs of wear. The x and y axis should move with only a little resistance. Don’t push them too fast or the back-emf can damage the drivers.
To set jerk, Google it (marlin jerk setting). The default jerk is 20mm/s, I prefer 15-12.
If you recently got the printer, contact printrbot support.
@Matthew_Del_Rosso that’s good info.
Your supply is probably OK if leaving the bed heater off changes nothing.
Now I suspect either the X-stepper (the physical motor) or the X-driver (the electronic motor controller) may be the issue.
What you now need is a speed setting that reliably causes print failures (if makes sense 
), so I would recommend running some new tests at 60 mm/s, presuming that will force your printer to fail.
Before the test, switch the motor cables for the X and Y axes, so that the Y axis drives the X motor and vice-versa. I am looking to see if the skipping stays with the motor, or if it follows the driver.
While you do this, check that the motor current pots on the board are set about the same for both X and Y, and also back the current off just a bit.
Here is a link telling you how to adjust the currents:
https://printrbot.zendesk.com/hc/en-us/articles/201877030-How-To-Adjust-Stepper-Motor-Current
The reason I want you to reduce the motor currents is that over-current can permanently weaken those stepper motors. Inside the steppers are current coils and permanent magnets, and there is a point where the coil current can demagentise the ‘permanent’ magnets, which cannot be recovered.
If the driver current has weakened the X motor by over-current, you don’t want to do the same to the Y motor!
During the test , if the same axis (X axis) is still skipping, the motor is suspect, but if instead the Y axis starts to skip, suspect the driver electronics.
After the test you should know if the driver or the motor is the problem, and you have the option to increase the current if the skipping is because of too little driver current, but I think that the Printrbot recommendation is no more than 80% of max. to avoid permanently weakening the motor.
Good luck!
so it turns out that my z axis didn’t fail yesterday on of my brothers had unplugged my printer, and my dad not knowing what happened thought that the low hum from the fan was the printer stalling and unplugged it. oh well guess that’s what happens in a family. but that still doesn’t explain the x axis skipping.