Is there something funny about Prusa PLA?
Dunno if this is the right forum on not, but...
My printer came with four rolls of filmante. Two colorfab and two Prusa. I've already printed-out the colofab rolls without any problem at all and yesterday I switched to the first of the rolls of Prusa filament and it has been a disaster. I'm printing out something that I've printed before with not problem. When I printed it the first time, I found the extruder just whizzing about in space, an inch or so above the print-so-far. What happened is that the filament *broke*, the extruder ran out of filament and didn't stop but just kept on printing [nothing].
So I cleaned all that up reloaded the filament and started the print again. I watched it for a while and it was doing great but a little while later I noticed that the printer had stopped -- some extruder fan error and the filament was all snarled up around the extruder. I cleaned everything up, restarted the print job and the *same*thing* happened: ext fan error and a snarl of filament all over. Could it be the Prusa PLA? It felt the same as the colorfab, but it certainly seems not to work. I'll try opening the other reel and see if I have better luck.
Here's what I saw when the printer died:
Re: Is there something funny about Prusa PLA?
No solutions, but a couple of things to consider.
1) If the nozzle plugs, the Bondtech gears are pretty good at gnawing away the filament until it breaks.
2) The filament sensor is OFF by default. If off and the filament breaks, the printer continues to operate as normal.
3) The Extruder fan has a tach, and if any of the crows nest of filament got sucked into the fan and jams it, the controller will stop the print. Check the extruder fan and heatsink for stray strands from the birds nest.
Re: Is there something funny about Prusa PLA?
3) The Extruder fan has a tach, and if any of the crows nest of filament got sucked into the fan and jams it, the controller will stop the print. Check the extruder fan and heatsink for stray strands from the birds nest.
That's what I think happened -- I don't think there's something wrong with my extruder. But *why* would that happen? With the colorfab everything prints perfectly and with the Prusa I get the bird's nest. I'll try switching to the other roll of Prusa and then back to the almost-out colorfab rolls I have and see what happens. Thanks...
Re: Is there something funny about Prusa PLA?
There are too many "whys" - it's a matter of where to start. Different filaments print differently. Even same brand and family but different color will trip you up.
There's the question of gcode. Are you using the same file to print with? If not, then you aren't really printing the same thing that worked before. Way too many things in the slicer that can change print experience. Did you upgrade firmware between prints? Not that that should affect things, but it's been known to happen.
As for Prusa sold filament? I doubt it's the cause of the problems (short of improper temps and similar application issues). Though one roll of beige Prusa filament I eventually used up had a coating of something on the first layer that made it impossible to use. I suspect handling or the plastic bag it was shipped in contaminated the surface. Once I got past that first layer the filament turned into one of the better I've used and I ordered more of it.
Based on the image, looks like there are only the four angled posts when the print fails. Even a brief clog or misfeed can cause problems. You might check the Bondtech feed gears are properly tensioned. And if that looks good, try a cold pull or two just in case something odd got into the nozzle.
Re: Is there something funny about Prusa PLA?
Thanks for the insights and suggestions. I realized that it is NOT the same object I've printed before -- it is a new and nearly-identical model and that's almost certainly what the problem is. I realized when you mentioned the struts -- something is missing!! There's supposed to be an object printed in between the struts!
The object is not really stable [it is "standing" on an edge, not lying flat] and that's what the struts are for. In a test print I discovered how much of the model I could print before it broke free of the base plate., and then I added the struts at a bit below that height to keep the model from rocking on its [precarious] edge.
I made a new, similar, model and I believe that i may have inadvertently positioned the object a few fractions of a mm higher on the plate. What's missing is the 1/4" or so of the model-in-the-middle between the struts, and know that I found it; it was *under* the printing plate. It has broken free and gotten knocked off the end of the printing plate and the extruder trying to continue to "print" the now-not-there object made the bird's nest mess. Back to the design program to tweak the location a tiny bit.. 🙂