PLA is grinding up the filament, BFB FAIL
Hi BFB fans,
I'm having a terrible time trying to print anything with PLA. The PLA is getting ground up by the screw on every print. The nozzle is not clogged and the screw tension is properly set at 12mm. Is there a problem with the supply of BFB PLA, can it be out of spec? I'm not sure what else to do, does anyone have this same issue and advice on what to do?
I think that I have a defective unit, a local tech (BFB dealer) told me that he thought it might also have a bad board since my motor #2 was starting and stopping during a print.
My next step is to return it. I actually expect a working machine for the ammount of money this damn thing cost. Maybe the BFB series hasn't quite worked out all the bugs yet, it seems that there are a lot of unsatisfied customers on these boards. In any case, I have not been able to print a single PLA part successfully. I'd love to hear of any solutions.
Hi,
did you already removed the old filament and cleaned from dust and make a restart with new PLA after the hotend coolded down?
Otherwise you will find a lot about clogging PLA in Forum search.
cheers
Hi Hank,
Grinding out on material is often either due to spring pressure requiring tweaking or the reel of material not being allowed to rotate freely (due to waste material finding it's way under the reel)? Both have caught me out when printing. Also, have you had ABS in the extruder previously that you are now running PLA through and do you always follow the guidelines about cutting a point on the end of your material before feeding it in to the tubes?
I'm intrigued by your print stopping at random, this has me wondering about the print file? Which Axon did you build the print with and when did you last update firmware?
Tim
I dealt with these EXACT same symptoms, and they drove me batty. I finally figured out that it was the extruder motor was simply spinning far too fast. Two things you can try here:
1) If you are so inclined, modify the gcode to lower the rpm of the extruder motor, both in the priming (M551) and printing (M108).
2) Manually adjust the rate as soon as printing begins by scrolling to the right in the print screen on the Rapman and quickly lowering the RPM. If the bearings stop clicking and the chips stop forming (which I suspect will be the case), then you likely have the exact same problem as me.
I finally concluded that there must be something wrong with my extruder controller or something along those lines. I have been able to print by trial and error - discovereing the speed values that work and manually modifying the gcode each time axon generated one. I am going to try replacing the extruder controller board now that BFB has sent me a replacement. I will report back.
Hi asifjahmed,
I've just reassembled my extruder after implementing the new drive shaft from Bits from Bytes and I'm still experiencing the same problem. I download the hollow calibration pyramid and ran it through Chylld's derafter and I managed to finish a slightly messy print. I'll upload a picture in a little bit. What values have you been using for the motors? I would love to know, it could save me a lot of time of trial and error. Also, let us know when your new controller board arrives.
I received the replacement extruder controller board from BFB, installed it, and VOILA - my problems are gone.
A couple of observations:
1) The printer is now MUCH QUIETER than it was before. I suppose this is how its suppsed to be, but previously when my extruder reversed (which happens hundreds of times per print), it sounded like a loud bird squeal, now its inaudible.
2) Most importantly, the printer now prints using the gcode outputted from Axon 2. I no longer have to manually modify all the extruder rates in the gcode.
3) Clearly, I was right all along - it was in fact the microstepping not working correctly on the extruder controller board.
@Hank - did you try manually lowering the RPM rate after the print begins? This will tell you whether this is your problem or not. As soon as the print starts, be ready to just hammer the down arrow on the screen (scroll to the right in the print screen and select the RPM rate) to bring it down from the default to loess than half that. See if the print seems to be doing better. This is easier to do with ABS as the raft will stick better under the ridiculously high extrusion rates. You'll have to do this a few times, as the raft layers and print layers use different RPM rates, and the print will always use what's in the gcode when it first switches, so just be on standby.
Hey asifjahmed
Just confirming that you are using the RapMan 3.2? I'm about to send an email off to support requesting a new extruder board.
Yes, Rapman 3.2
What kind of speeds worked for you in your printing? I lowered mine down to about 20 and it didn't help me. I do hear clicking every few seconds from the extruder.
Hi Hank,
I've been dealing with the same exact problem as far as the PLA is concerned but haven't had the problem with the motor. What printer are you using? I have the RapMan 3.2. I've contacted BFB Tech Support and they said that I may have a faulty drive shaft. They are in the process of shipping a replacement one for free. I would try contacting tech support with pictures of you extruder. I wish you luck in fixing your printer! Let me know if you figure it out.
-Mike