PETG works fine, but cannot get PLA to print
Using Prusa PETG, just about works perfectly. However, when I try printing using Prusa PLA, it always seems to stop extruding very shortly after the start, even during the Z-bed first level calibration. Very weird. I have tried heating up the nozzle (to 250) for a while to melt out any PETG, also did some cold pulls with some PLA. did lots of purging after loading a brand newly opened prusament white PLA, and it does seem to extrude fine when just doing the "purge". But as soon as I try the first level, the filament stops coming out. I do hear some intermittent clicking from the extruder, also. It sort of seems as if it is having trouble extruding. Is it worth trying different temperatures? Is it a defective extruder? this is pretty new, and has never been good at PLA, so it's fairly frustrating. thanks for any suggestions
RE: Same here
I am having this exact issue. I would be very curious to hear the suggestions.
When you switch from a higher temp filament like PETG to a lower temp filament such as PLA it's important to do the purges at the higher temperature. You did you tried purging but didn't specificy at what temperature. I usually load PLA (after printing with PETG) at 250 degrees and run a couple of extra purges. If you load PLA at its usual temperature, you risk having PETG residues stuck in your hotend because the PETG won't melt
Purging
I also purge extra and often use a purging filament that is superficially made for this purpose. The bottom line is that purging a filament requires that you completely remove the old filament and not just to when you think the color is close.
--------------------
Chuck H
3D Printer Review Blog
raising hotend
Thanks for the suggestions. I did try upping the temp and doing lots of purges, as well as trying to clean out even invisible residual PETG. I took out the white tube from the extruder and looked in, and all looked clean. Still had the same issue. I finally googled "clicking extruder with PLA" and ended up at this YouTube video, that recommends raising the hot end. I've tried that now, and also re-adjusted the PINDA to compensate for the raised nozzle. Trying it now, will report back if it solves the issues. thanks again
RE: solved the issue and now better than new
Ha! I think that was the issue, hot end was too low. Strange, because I purchased it pre-assembled and assumed, but you what they say about that. It now prints PLA great, sticks well, and extrusion looks quite acceptable. In addition, it seems to have fixed a previous issue I posted about here weeks ago when trying to make a lithophane (using PETG) where there would be occasional globs of burnt filament on the back.
