Printing with eSun PETG on a Simple Metal (Ceramic Ubis) with a 0.6mm Nozzle – really struggling to get this tuned to print as cleanly as I’d like. I’ve spent days trying to fine tune my retract configuration but there doesn’t seem to be a happy balance.
I’m currently using 0.70mm retract distance, 20mm/s retract speed and 1.0mm wipe distance. I’ve of course tried more/less of all of these individually. Generally speaking my prints look pretty good except for any area where retracts there is a high concentration of retracts. I have other prints that show similar issues, but this is by far the most obvious.
You might not want to bother with wiping PETG. The more time you spend next to the retraction seam, the more issues you’ll have.
0.6 nozzle is also going to be a bit tough, as PETG has very low viscosity at ideal printing temps.
Try dropping your temps some to increase viscosity a little bit, but not so much that the part becomes brittle.
Keep in mind that 20mm/s retract doesn’t mean much if your acceleration is low. Extruder acceleration often has much more to do with how “punchy” your retracts are than speed as you likely never reach that speed. Try to get away with as much acceleration as you can on your retracts, and make sure your travel moves are fast enough and with high enough acceleration to not waste any time drooling on the seam.
PETG can be a pain in the ass, but it is a great material once you have it dialed in.
I think you have two issues. 1 is the temp could be too high. I have been printing esun PETG for a month of so now and I find that it has issues if you run too hot or cold. Also, I used the same retraction settings that I had with pla and really had good success. The second problem is your nozzle size. You probably want to drop to something like a .4 to get it to drip less.
I personally do not like the air moves that the slicer is showing in the preview. I see no point in that much air moves. I also think the part would be much better turned into a folding piece printed flat on the bed with a little overlap for the one triangle that is in the middle. I personally can not comment on the PETG settings.
I don’t think I’ve tried completely eliminating wiping. I was hoping that the 0.6mm nozzle would help me combat the relatively slow(er) speeds required for PETG. Honestly on most parts it looks fine. I have a new 0.4mm nozzle on order and should have it this week.
Lowering my temps any further gives me really brittle prints (currently at 240C).
I don’t have my exact configuration in front of me, but acceleration is configured very similarly to the default Printrbot settings (https://docs.google.com/spreadsheets/d/1FntcZTm4M7FzUf9ej9DEmRYf1LaH76J8TU3VzK3Ox8g/pubhtml). I do know that I’ve decreased the X/Y acceleration to 1000mm/s^2 to reduce ringing.
I’m confident that my steps per mm (and extrusion width) are dialed in perfectly. I’m definitely open to suggestions on how I might change the extruder/retract acceleration to improve things. Thoughts?
240c is exactly what you should print IMHO for esun PETG. I think the nozzle will help a lot. You might also want to up your travel speed. Mine is at 70mm/s for reference. I can send you my Cura profile if you want to see my PETG settings, but it isn’t for a simple metal. Should be comparable though
