Hi Folks,
I have a couple of printers and fitted them bot with E3D hot-ends around six months ago. Good results mostly, but I noticed things getting progressively worse over the last two months. Am using natural and white PLA at around 180 C. Pretty heavy use - perhaps 6 hrs/day. Printed parts began to fit very poorly. Decided to design and build a simple calibration cube ( box really 40 * 40 * 40mm, with 4mm walls, no top). The external dimensions of the cube were pretty much spot-on, but the width of the walls were 4.5mm. I really can't understand this. Anyway, did an extrude into free space and the resultant, cooled, PLA is around 6mm! (the original nozzles were 4mm). Both machines are the same. I could understand it if I were extruding something abrasive (unless white is abrasive). Larry K has previously mentioned 'die swell' at about 5%, but 50%!!!
Have bought another couple of 4mm brass nozzles and a couple of hardened steel ones too. I know brass is a soft metal, but should I really expect that much wear. Perhaps you all should periodically do a free extrude.
Regards
Chris H