2 layers in. peek too hot and it backed up and clogged again… this STL fan shroud blocked more air flow than it allowed through and the air was coming out the back side of the fan, so the peek was getting none of it… so im going to try to original fan now, at 195 degrees, instead of 210… otherwise ill have to find an open air fan mount (there is one around, but thats a layer fan, not a peek fan
I skimmed this post but get the gist. I’d recommend reading my posts in my signature. One area that could be causing this issue is what I call PLA jamming - it’s caused from using too fast and too long retract. What are your retract settings? For PLA the retract speed I’ve found anything over 25mm/s can lead to these sorts of filament starving problems.
I don’t know if you’ve printed the dissected part and posted results yet but I am going to make an educated guess that the bottom part will print fine and you will still have problems with the top part. It isn’t the height of the part, it’s the geometry change with the multiple fin-like things. I bet you are seeing/hearing more and more retracts taking place as this part of the object prints. The photo also seems to show some starving artifacts at lower levels too on the conical section. Also an indication of PLA jamming starting to occur (I’m looking at the layer lines that look incompletely filled).
I went back and read the entire post now. You mention hearing a few clicks from the extruder earlier in. That’s classic skipping steps on the extruder stepper motor.
The peek area getting hot can be perplexed by retraction settings. But these hot ends do also need to have good continuous airflow. I have mine set up to power on the peek fan the second the printer is turned on. If you wait until it is starting to melt the filament, it is too late. When this happens, its all over until you clean things out. Also do the minimum extrusion temp test and try printing at the lowest temps you can. The stock fan and shroud should be fine if you have it set up well and it is powering full on before melting starts.
I know it’s a dumb question, but are you shure you mounted the fan in the right direction? The duct should work, even if it’s not great on aerodynamic but at least there shuld be no significant flow back out of the fan that can be noticed by hand…
Second step, can you feel the air flow on the heater block (when it’s cold…)? Maybe air is getting there, cooling your hot end and cause it to yam…
Thanks for the response sebastian.
Yeah it was on the right way, for sure… And when it wasnt mounted to that shroud, the air flow was insane. In fact IM now printing with a different shroud. http://www.thingiverse.com/thing:368303
This one is more open, im about to mount and test it.
So im going to use the stock fan 5v on that side, and this 40mmx10mm 24v fan on the other side.
To your second question. The heater block isnt the issue. Because each time its jammed im left drilling out the Feeding chamber of the hot end. its halfway up there
can you post a photo of your entire hotend?
i ended up taking off that 2nd printed fan because it was too tall and was hitting the bed… so im working on a re-work… right now the entire hot end setup is 100% stock
mhackney, glad you are over here… are you a taz owner? i know we both had (maybe you still have it) a rostock max.
Is there a firmware line in my configuration.h to make sure the fan powers from the start? it looks like it does as soon as the board powers on (the 5v fan that is) so maybe the newer taz’s have it always on.
so im printing a test tower about 175mm tall and relatively narrow to test some settings.
i lowered the retraction from 30 (s3d stock setting) to 10. Also slowed down the print to 40mm/s however its running slower because its so small.
So that begs the question.
What speeds can we realistically be running our taz’s at ?
If i want some rapid prototyping of large objects in PLA, am i stuck at 50-60 tops? maybe less?
ABS since it doesnt suffer from heat creep, higher?