I'm currently using a MakerFarm Prusa i3v 8" printer with IC3D black filament. When I run the filament into the extruder, close and lock down the idler, then use pronterface to extrude the filament I get roughly 10mm of effective extrusion. When I continue to try and extrude filament, the hobbed bolt rips into the filament, tearing the edge of it. This puts small flakes of plastic into the grooves of the hobbed bolt, as well as in the extruder. I've disassembled, cleaned and rebuilt the extruder about 3 times now without this issue being resolved.
I'm using a 0.35mm J-Head hot end, which I've ready can make the filament harder to extrude since the smaller nozzle means it requires more pressure. I've also been told by Colin at MakerFarm (basically the most helpful person I've ever met) that IC3D filament is not that great, as they did not support it at their company due to what they claim is its disappointing quality.
I've included an image of what's happening to the filament:
The MakerFarm Prusa i3v build guide includes a page dedicated to this issue specifically, which says:
(Note that I have read this and adjusted accordingly. The problem still persists)
Troubleshooting:
My hobbed bolt is chewing up the filament
First is we want to check out speeds for pronterface and for Slic3r, for pronterface make sure the
extruder speed is set to 30mm/min (to the right of the Reverse button) for Slic3r make sure you use
the Slic3r config file from page 31 of this guide and make sure you have slic3r version 0.9.9, if you
upgrade past 0.9.9 you will have print issues.
Next look at your extruder, we want to make sure the idler bearing turns freely when not in contact
with the filament or hobbed bolt. If the idler bearing does not turn freely check to make sure it isn't
rubbing on the hinge part of the extruder block, also make sure the bearing isn't hitting plastic inside
the extruder idler.
Next is Temperature, for Jhead hot ends ABS use 225c, for PLA use around 205c. For the Hexagon
ABS use 250c and PLA use 225c. If you are using PLA you may also need a fan to blow on the
black peek plastic part of the jhead hot end to prevent heat from building up causing jams, for the
Magma PLA is not supported.
Next is the print material used, ABS is the easiest material to print with, I would recommend
everyone start out with ABS to get you printing, after that you can experiment with other materials
that take more effort to get printing. Also make sure you have good quality filament from a good
source, there are many places that sell sub par filament that won't work and just cause problems. I
would recommend using Makerfarm, Ultimachine or Makerbot filament as they are all known good
sources, you can measure your filament and make sure its 3mm, if its above 3mm it can cause issues
and jams, cheap filament also usually has debris in the filament which will cause jams and other
issues.
Next if your X axis isn't level this can cause your nozzle to have to much back pressure. If you tell
your printer to home the nozzle should end up in the back right corner of the heat bed glass. If you
now move the nozzle to the left side of the printer check to see if the nozzle moves farther away
from the glass or if it moves closer to the glass, if either happens then you will want to hold both of
the 5mm threaded rods attached to the Z motors and turn the left one until the nozzle is the same
height away from the glass on the left side as it was on the right side. If you upgrade your slic3r or
are not using the slic3r config on page 31 of this guide your Z Motor can easily get out of calibrate
causing this issue.
Next check your spring tension, if the springs are to loose there won't be enough grip on the
filament, if the springs are to tight the filament will be squished causing it to be oval instead of
cylindrical which will cause it to jam also. You should be able to pull back on the Extruder Idler
with your thumb to pull out or put in new filament, if you can't pull out the filament your springs are
to tight.
Last if there is something physically blocking the nozzle it can cause the same problem, if you have
a .50mm or .40mm nozzle you can straighten out part of a pen spring, then when the hot end is at
temp for your filament you can push the spring up into the tip of the nozzle, then set your
pronterface speed to 10mm/min and extrude to see if that unclogged the nozzle. If that doesnt work
you will want to separate your hot end from the extruder, then when the hot end is at temp push in a
alan wrench or screw driver that is 3mm into the hot end while holding onto the hot end mounting
plate, this should force out any filament in the hot end clearing out any debris.
Edited 1 time(s). Last edit at 07/16/2014 12:09PM by Zulfe.