For some reason when I was printing a test piece an odd shifting occurred. It seems like the printer shifted, but the opposite side continued to print straight.
On the right side, some of the infill is not complete for some reason as well, the main problem is on the bottom though. I have no idea how this happened, especially since without the rods the x/y assembly slides smoothly across when the printer is tilted.
Also the hole in the middle is where i failed at removing an object from the buildtak and cut it, oops, but it’s unrelated
Shifting means the corresponding axis is blocked temporarily. If your axis are OK then check if the belts are not too tight. Also clean the moving rods as oil+dust acts like glue and can block the sliding. Another possibility is overheating (motor drivers). With this summer’s temperatures it can happen.
I know I called it shifting, but shifting isn’t really the best word to describe it, I’m just not really sure what else to call it. If it was a “traditional” shift, all the entire layer would be moved, hoever this is not the case because the outer dimensions are the same.
Here’s a picture of the problem: imgur.com/nl4nPxj
I then re-tensioned the belts and pulleys and now when I printed a cube the Y dimension was 5mm to short. With all the problems I’ve had though, each issue seems to be with the front face.
On your first picture there’s a layer shift. On the second one it looks more like an over-extrusion. Lower the temperatures to 190-195° (for PLA) or 220° (for ABS) and lower the flow to 70-75%.
I tried to take a picture from the side this time. As you can see (I hope), the layers didn’t shift, but that one particular side isn’t right.
I’m not entirely sure what you mean by over-extrusion, do you mean that the nozzle is going to far or something like that? In this picture you can see that the outer length with the hole in it is the right length (20mm give or take)
I print another cube where every face except the front was fine (minus a few extra bubbles, but I think that’s related to the problem). In this one, the front face was just shorter than it should have been and it didn’t have the extra layer of plastic that the other 2 did. For some reason they all seem to have a second perimeter 4.5mm back from the one that should be there.
I’m probably not doing a good job describing what is happening, and that’s partly because I don’t even know what’s happening. Hopefully I did a good enough job describing this odd problem this time.
For PLA you should drop your temp to 190.
Change the retraction to 4mm and the retraction speed to 110mm
This will not fix the shifting but will help with printing.
[quote=“Wrong Way”]For PLA you should drop your temp to 190.
Change the retraction to 4mm and the retraction speed to 110mm
This will not fix the shifting but will help with printing.[/quote]
Thanks, I’ve already updated my settings and I think they have made my prints look a bit better. I think the less retraction should help with ooze on the side of multi-object prints.
Anyway, I got a new stepper driver and it doesn’t seem to have made much of a difference. I printed a test cube and the infill seems to be really weird.
The first layer is the right length, but the rest are 2 mm shorter than they should be. It didn’t shift though as seen in the second picture, there is no shifting on the back edge, and in fact, all the faces are smooth. It’s kind of hard to see, but there is a group of bubbles (second picture) that exist in each layer, presumably where the extruder “stalls” or something and is the cause of why it is shorter than it should be. It’s also non-existent on the other side. If the X/Y carriage was getting stuck, then the front and back faces of the print should would not be flat. It is somewhat hard to see, but in the infill (for each line it makes it seems to go over it twice) half of each line is off and in the middle of the the other two lines, like it drifted away from the proper infill (not obvious in the picture, but in the good half of the infill, one of the segments drifted from its path. It seems to be doing this on each layer as if it were the proper infill.
Hopefully I didn’t just confuse whoever just read this.
EDIT: I forgot to mention that all cubes that i have taken pictures of (including the one in this post that I stopped early) have of been from the same Gcode file on the same SD card. I just wanted to make sure that that was clear.
The default flow rate is also too high : you can drop it to 70-72%.
Your infill is weird indeed : it looks like there are 2 different infill %.
The “bubbles” on the side are where the head changes direction (either it prints one layer clockwise and the other counterclockwise or it stops for a short while waiting for the Z height to change) when printing and is oozing a bit at that place.
I know it looks like it’s two infill percents, but actually one of the strokes on each line of the infill has drifted off. I tried to trace over the infill to give a better idea since its hard to actually see in the pictures.
I drew it as best I could. The only main problem I see with my drawing is the thicker lines should be square (because they are correct) note that the smaller infill is not square and curved in some places. The rest of it is fairly accurate, the infill seems to split into the weird pattern. I think this should give a better idea of the problem and someone will have a better idea on what the problem is.
[quote=“mikek”]Hmm… I think I have seen something like this before… can you check if the pulley on the corresponding motor shaft is still well attached?
Mike[/quote]
The pulley is on the motor, aligned with the D shaft and tightened with thread locker. I don’t think it’s going anywhere. Any other ideas on what it might be?
I don’t think they’re too tight or too lose, but I’m not sure what the right tension should be. The only thing I can think of is that I stripped the XY Linear Bearing Clamp 2s (the half that goes attaches the perpendicular rods) when I was originally tensioned the belts. I tried tensioning the belts with 16mm bolts instead of the 12mm ones. I ended pushing little circles into the clamps and might have stripped the inside that keeps the bolt in place. I’m not entirely convinced that’s the problem though, since I can still tighten the belts to a reasonable tension.
[quote=“mikek”]Hmm… I think I have seen something like this before… can you check if the pulley on the corresponding motor shaft is still well attached?
Mike[/quote]
The pulley is on the motor, aligned with the D shaft and tightened with thread locker. I don’t think it’s going anywhere. Any other ideas on what it might be?[/quote]
Hmm… if you are sure the pulley attached to the motor is tight and can’t be pulled of the motor shaft when pulled with moderate force (they have a tendency to work them self loose, at least on my printer) then that can’t be the issue.
I tried loading your gcode into Repetier and nothing obvious wrong with it (my printer is busy, so I can’t try to print it myself right now).
Looking at the sides of the cube you can see that there is a line, like over extrusion corresponding to where the “shift” occurs on the inside of the print, so it looks like there for some reason is a place where the printhead isn’t moving as it should - the question is why…
I would double check that all the pulleys are tight on their axis and can’t be shifted sideways, not just the one on the motor, and that the printhead moves freely when there is no power connected to the printer, it shouldn’t suddenly come loose and then tight again around the place where the error is happeing on the axis.
I don’t think it’s because of the tension of the belts, my guess is that it would give a different kind of error, but I have been know to be wrong about my assumptions… Apart from that I’m a bit blank to what the issue could be…
All the pulleys are tight on their rods and cannot move back and forth. I have noticed that with the problem, there has been a mysterious clicking sound for every full rotation of the pulleys on the Y axis. The best I can describe the sound is if someone tied a zip tie to a rod and spun it around the it kept hitting something. I haven’t been able to locate the sound besides it coming from the front half of the Vertex, and nothing seems out of place. There also seems to be another sound that sounds like plastic rubbing on the metal rods (also Y axis). The strange thing about all that, is the Y axis moves much more freely than the X axis.
I also printed a new thinner spool holder which once again had problems with the leading edge. Here’s a link for test prints thingiverse.com/thing:960116. If anyone can actually print it I’d take some feed back since I can’t do it myself currently I’ll post it in the upgrades thread too when its done.
This time, the leading edge is just flattened instead of being curved, oddly enough though, its not just flattened, but there are multiple depths of where it’s flattened. It’s not like it just cut the print off at a certain Y axis, because there are further extrusions than just the main one.
Here’s another view of it. some of the holes are seen to be really messed up. The right side is the leading edge of the print from this angle.
I assume that the issue happens on the same place on the build plate each time? - so that if you position the part at a different place - like in the back left corner in the software and then print, then it would have the error in a different place? (or no error)?
If that is the case, is it only one place/line on the buildplate that has the issue, or is it happening in multiple places?
It’s not just that location on the build plate. I printed another one horizontally, and this time it was 2 mm shorter in length, and the other one was 2 mm shorter in width. Both were shorter in the direction their leading edge was in. I guess I should also print it with a 90 angle on the Z rotation to just make sure. When that print is done, I’ll put pictures of all 3 for comparison.
I’ll post it in the upgrades thread too when its done.
