Hi, I hope someone can make some suggestions on what's going on here.
I needed to print a simple cylindrical part and put it in a group of more complicated pieces, sliced it with Slic3r 1.2.9 on Repetier Host and sent to print.
I checked in later when it was about 5 mm high, and found the inner and outer perimeters covered in 'warts' as shown in one of the top two in the attached photo, so I aborted the print, although the other parts looked okay. I removed the cylinder from the slice group and sliced again. The more complicated parts printed fine and I assumed the large group was maybe straining the printer's memory. I tried again with just the cylinder and it did exactly the same thing (see the other print in the top row), so I aborted again and once more under close scrutiny. It printed fine for about 3 mm then it printed some crazy lines across the perimeters. See lower print. The slicer image looked fine and I just can't think what could cause this.
I use mainly Slic3r without too many problems, and am quite surprised that this would happen on such a simple part. I then sliced using Cura and that printed the cylinder just fine, so I am not in a panic about this but I really would like to know the likely causes so I can be aware for future prints.