Airwolf HDx, ABS: printing parts with combination of large, flat surfaces with 4 tall columns at the corners. Print goes along great but it seems like all of the retraction causes the filament to erode and eventually "mouse-bite". I've actually saved a couple prints my manually pushing the filament into the extruder when I saw the layer started to skip and make uneven layers. Taking the retraction completely off makes for a really bad print cosmetically.
Is ABS more prone to getting ground down from retraction and eventually leading to a Mouse-Bite?
ABS is not any more prone to 'mouse biting' when compared to other materials. First suggestion would be decrease the retract length so the hot end can maintain a more constant temperature. If that does not work, I would next recommend kick the extruder temperature up 5 degrees for printing - that can have a profound impact when printing small parts far away such as the posts in the corners. If you have any more specific questions feel free to email Support.
Thanks for the reply. I think I may have discovered the underlying cause of the mouse-bite issues. It seems the hob gear (the metal extrusion gear)that pushes the filament through the extruder was not centered in the line of feed. A manual alignment of this hob gear has since achieved good results and have had less failed prints. The whole time I was assuming it was my slicing settings or temps, but off-center hob gear was causing excess wear on the filament and eventual slippage.
I found this solution from a friend who was having similar issues on a different printer. I hope this might help others if they stumble across this issue.
It sounds like you probably have solved it already, but I've found that the pressure is indeed the reason. Sometimes raising the hot end temperature can help, but usually implies it was back pressure (not melting fast enough). Also, if you switch between PLA and ABS, you might want to back the pressure off just a bit on the extruder gear--that worked for me. It could have been slightly different tolerances in the filament diameter, or it could be that ABS is a bit softer than PLA.
Me again... I found another issue the other day that helped further alleviate my mouse-bite issues. The pressure lever on the extruder assembly (the lever that has the spring and applies pressure to the bearing) was loosening up a bit. The hole that receives the lever locking pin was becoming wobbly. I put a bar clamp over the whole assembly to apply pressure to the bearing and spring (essentially bypassing the work done by the locking pin) and voila! No more mouse bites.
Wish I could post a pic but hopefully the description above makes sense.