Fuzzy/Rough after 20ish layers.

Hey folks, I am starting to print with my robo after too long of a hiatus. I have fixed my problems with the print detaching from the bed. Now when I print after many good looking clean layers, the layers start to become fuzzy/rough from the head dragging. I wonder why this could be, why does it seem to start dragging after 20 or so layers. I figure this is the problem as the layers seem to look better when I manually adjust the screws to raise a small amount. Thanks!

 

My experience of this was caused by the hobbed bolt and temp settings. After things heated up (20 layers or so) the feed rate messed up the print. However, even after getting those two things narrowed down, I was still getting problems and ended up switching from an e3d to a hexagon hot end. Once initial teething problems were solved (it was a beta model hot end), everything has been working just I need. Love the hex.

 

Hmm it seems like it is a layer height thing. The reason I think this is that my last few prints I have noticed the head dragging making a poor first layer but if I raise the head a little so this isnt happening the filament doesn't stick to the bed when a new piece starts...hmm any help is appreciated.

 

Also be sure your zaxis isnt slipping. If you get nice clean layers and then start dragging later on it sounds like the threaded rods are not spinning with the motor or the motor is not spinning enough. Good luck