This is the second time I’ve ever had to deal with “shifting” during printing. It has only occurred on larger prints and this time it was with a different hotend, so I’m blaming it on Slic3r I guess…
Anybody else have this happen often? I did scale the model up 1% because it wouldn’t slice without doing so.
Previous print was fine…
Any experiences with this before, and did you even have to make any corrections or are these just freak occurrences?
Besides combing through the gcode how am I supposed to know if this will happen to a print in advance if it is happening while slicing?
It’s unlikely to be a slicing issue, it’s more likely that your machine is slipping along that axis, especially if that axis is belt driven. Another possibility is the build plate itself shifting during the print if you have a mobile table instead of a stationary table.
You could load your gcode in Repetier Host to visualize it, but I can pretty much guarantee that those shifts aren’t in the gcode. What you do have in the gcode are long, rapid travel moves that probably cause your machine to exceed its speed/acceleration/jerk limits.
What kind of printer ? This can happen on an Ultimaker if they rods don’t have enough lubrication.
Another really weird thing has been happening since I’ve installed the E3D hotend @Whosa_whatsis … It seems as though the printer is just going at whatever speed it wants, no matter what I slice it at. I guess it’d be better to upload a video, and I haven’t done any troubleshooting on my own yet, but this print I had set to do the perimeters at 35mm just to see what it would do and I know it was moving at a rate near 70-80mm for the whole print. Bridges and gaps set to 20-30mm and it just kept printing as fast as the perimeters… Unusual, and I should go through my last firmware upload just to see what might have changed. Any other suggestions?
@Daniel_ShadowDrakken table is solid, and all belts are snug.
@Shachar_Weis Mendel90 kit, e3d v4.1 hotend
Slow down the acceleration and see if it helps
I want to print this in pink PLA for my niece.
Nice model. Could you share the STL file?
@John_Latimore s http://www.thingiverse.com/thing:257911
@Nuker_Bot_NukerBot_3 G I printed it in pink as well scaled to 75% for my daughter.
It’s a cool model that has moving legs and head after printing in one piece.
I have had this happen in both Cura and Slicer. Model gcode visualizes correct. Happens on the same spot/layer repetably requardless of speeds an acceleration. I know it is not a shift on mine because it is not across the part like a slip/shift. Only on one side of the part.
I’ve seen this happen many times before installed a fan for the controller. The stepper drivers can get very hot, and if they aren’t properly cooled they will go into thermal shutdown and the steppers will miss steps. Also if the stepper motor gets too hot the resistance in the coils will change. Lowering the maximum jerk and maximum acceleration helped, but cooling the stepper drivers helped the most. Also slowing down all the print speeds made some difference.
There is a kludge for this behavior that is easier than properly tuning your printer, that being to home X and Y between layers. Any shift will be corrected on the next layer, and on average, 50% of a layer will be incorrect. I discovered this when doing timelapse prints, as I home X and Y before taking a picture between layer changes, so the part is always in focus of the SLR controlled by my printer.
I also experienced this on a Prusa i3. Initially, I thought the problem was heat, but in my case a bearing was going bad. Have you ever witnessed the skipping? It should be clear from the noise if a stepper is skipping steps due to mechanical stress.
Either way, get a fan on that controller if you don’t have one already. It will save you time later. Nothing on the board should be uncomfortable to the touch.
@Matt_Harrington I already have active cooling and balanced the current so I don’t think that’s it. It always seems to stem off a radius/fillet feature. I will upload some images later.
I’ll double check all bearings this weekend @Matt_Harrington n and also feel for overheating on the drivers @Chapman_Baetzel . It’s a melzi board so I hope there isn’t anything wrong with them or I might be stuck replacing the whole board… I’ve got a ramps backup just in case though, that I use for testing with the @BotBQ Q.
Noticed another guy having the same issue on this print as well: http://www.thingiverse.com/make:68703
