layer shift only on some prints and only first few layers
So this is a weird issue just happened last night.
Was printing a filament guide thats two parts and it snaps together. Pretty small part, maybe .75" tall and 3" long, 1" wide. About the same size as a benchy just a little shorter.
Took a hour to print at .15 Optimal settings in PETG.
The first 7 layers printed at a 45 degree angle instead of straight up off the build plate like it was supposed to, was a consistent 45 degree angle no variance which i thought was weird. Then the rest of it printed straight up as normal, so this left me with a lip on one edge and a rounded edge on the other side, of both parts, that were supposed to be square 90 degree angles.
I recently installed my Pi and am using octoprint now via USB, have had several good prints since adding the Pi though so i dont think its the issue. I inspected the Gcode, the gcode is fine the printer just isnt printing it correctly, even looking at the individual layer Gcode in octopi as its printing the printer thinks its printing it correctly as you watch the gcode screen in octoprint but in reality its printing sideways for first 7 layers only, then straight as an arrow after that.
Thinking i had a hardware issue i checked the axis effected(which is the left/right axis the extruder is on not the heatbed axis) and everything is tight and bearing are still very smooth belt tension is 220 and no obstructions. Moves very freely by hand, i used the misumi bearing during assembly not stock, nothing on the extruder itself is loose i checked it very well.
So then to rule out a hardware issue I did several more prints, none of which had any layer shifts at all, printed a perfect marvin, a perfect benchy, and then a tower model about 5" tall just because i wanted something tall and narrow to test for layer shift, all 3 prints came out perfect not one single layer shift on any of them. I think having three perfect prints, which i put in the same spot on the build sheet as the filament guide pieces, rules out hardware error, if something was loose it would effect all prints right?
So now im stumped, any ideas?
Re: layer shift only on some prints and only first few layers
maybe worth mentioning the last thing i did before those 2 prints was update firmware to newest released 3 days ago. 3.3.1 i think it was.
Re: layer shift only on some prints and only first few layers
On a buddies suggestion i tried it again, with crash detection turned off.
It printed fine.
Not sure why Prusa is going nuts with all this tech that doesnt seem to work, filament sensor is a joke, now looks like crash detection causes more issues than it fixes. I guess i should be happy it works and turns out good prints even if you have to disable alot of the features.
Re: layer shift only on some prints and only first few layers
On a buddies suggestion i tried it again, with crash detection turned off.
It printed fine.
Not sure why Prusa is going nuts with all this tech that doesnt seem to work, filament sensor is a joke, now looks like crash detection causes more issues than it fixes. I guess i should be happy it works and turns out good prints even if you have to disable alot of the features.
because it moves boxes off the shelf, this aint rocket surgery! Having said that, these, what could be described as 'extraneous' features have the potential to become truly valuable give enough development. Prusa has recently devoted more resources to its software development department, and I have high hopes that this will lead to a more pleasant user experience, because I suspect a lot (if not ALL) of the problems we experience are scattered throughout the various software layers.
Re: layer shift only on some prints and only first few layers
I mostly agree. I've had many small issues with the printer since I got it, I only posted a very small portion here as I always troubleshoot myself and read the manual before posting and the troubleshooting portion of the manual is actually pretty good.
Most of these small issues turned out to be software related I've had only one actual hardware issue when the tensioning bolt on the left side printed part on the extruder belt assembly loosened and my belt tension dropped, not enough to skip a tooth and have bad layer shifts but enough to have some ringing on prints, this was easily discovered and fixed thanks to it being among the first things to check if you read the manual, it mentions checking belt tension.
Overall I'm a happy customer, just finished my 4th roll of filament and it's only been together for a little over a month or so. Just did my second service check on the printer, all frame bolts are still solid, all printed parts bolts still solid and all bearing still silky smooth. This printer seems to not mind a 24/7 operating environment, it's been rare that this thing has had more than a few hours off at a time since I assembled it, it's never sat idle for a whole day even.