Leaky extruders
-
@sungod3k Do you mean it leaks from somewhere other than the nozzle tip, or do you mean it simply oozes out of the nozzle? What are the conditions under which it "leaks"?
-
@deckingman leaking directly from the nozzle. And it leaves blobs everywhere. For such a short filament path and comparatively medium to high retraction it leaks too much
-
@sungod3k I'd say that oozing is normal for a longer melt zone and bigger nozzle. You could try lowering the temperature or use different filament with a higher viscosity.
-
@sungod3k said in Leaky extruders:
And it leaves blobs everywhere
When using slicer-retraction, it would be possible to check the "wipe while retracting" box to get rid of the blobs. But with RRF firmware retraction, it's not possible.
-
@sungod3k For what it is worth here are my PrusaSlicer settings for my direct drive Hemera with Volcano and 0.6mm NozzleX nozzle.
0.6mm Retraction length.
20mm/s retraction speed.
20mm/s de-retraction speed.
0.15mm extra length on restart.
Minimum travel after retraction 2mm.I found going slower on retraction was more effective than going faster.
The volcano drools everywhere while travelling and I have not been able to stop that. I have just accepted it.
My other printer uses an E3D V6 hotend with LGX Lite direct drive and 0.4mm NozzleX nozzle. There were zero issues getting that dialled in and it leaves no stringing at all.
-
It would be cool to have a nozzle with e.g. 3x 0.2mm holes instead of a single 0.6mm hole. Same cross-section but less oozing. We usually print wider than the nozzle diameter, so the three holes wouldn't have to be very close.
-
@o_lampe said in Leaky extruders:
It would be cool to have a nozzle with e.g. 3x 0.2mm holes instead of a single 0.6mm hole. Same cross-section but less oozing. We usually print wider than the nozzle diameter, so the three holes wouldn't have to be very close.
Interesting hypothesis - but your maths is wrong. The cross sectional area of a 0.6mm diameter nozzle is about 0.283mm^2 and the cross sectional area of a 0.2mm nozzle is about 0.031mm^2 so three of them combined would only be about 0.094 mm^2. To get the same cross sectional area as a 0.6mm diameter nozzle with three smaller holes, you'd need each one to be about 0.346mm diameter.
But it's still an interesting idea..............
-
@deckingman Right, I calculated the three circumfences, my bad.
It would make more sense to try this with a nozzle diameter bigger than 1mm and use 5 small holes.
If I had a lathe, I'd turn down a small brass gear and pressfit it in a big nozzle. -
@o_lampe yes prusa slicer has an option for that but I didn't notice much difference
-
It's definitely normal that with a volcano length heater block and nozzles, you will tend to have a lot more oozing. Key things to do there are calibrate the printing temperature (you can generally print with a lower temp than with a V6 style heater block)
First thing to look at would be the temperature. I had a friend that noticed they needed to print around 10-20c cooler on their artillery than on a similar hotend. I suspect that on his machine, the temperature is not quite accurate, where it's reporting the temperature as lower than what it should be.
Based on those two, I would say that focusing on the temperature would be a good idea there.
-
@ComedianTF2 yes i suspected that much, but its good to hear this from someone else. ill dropped the temp by 10C and added a z-hop and optimized the travelpaths. lets see how that turns out.
