Been experimenting with the printrbot geared extruder a bit, first impression was that the force needed was more than I expected.
Looking closer I noticed I didn’t have the gears perfectly lined up. One was maybe 0.1 mm off. After adjusting things went much better.
Not ready to test yet, I am printing a fan shroud for the stepper motor first since this puppy will get very hot, I think.
I would think it might get less hot than a non-geared extruder, because it’s (in theory) more efficient. And standing still is what makes steppers hottest. But I could be completely wrong.
@paul_wallich
The force needed is still a lot more then my Wades extruder. (3mm). So…yes, you could be competely wrong.
Then again, maybe not.
Ah, I thought you were going from a direct-drive extruder. Mine definitely got hot with 3mm, and the idler friction was substantial.
@Rien_Stouten you’ll definitely need the motor shroud for it. Don’t run that extruder without one.
Even non-geared extruder is hot when working heavy! The key element of “hot” is how depth that filament tooth get!
The torque multiplication of the gear reduction helps the motor push the filament more easily. Take the gear reduction away and it is tougher for the motor to push, but it’s being done routinely. Non-gear-reduced systems works fine for 1.75mm filament, 3mm filament is a tougher push and might not work as well.
Driving both sides of the filament should reduce the need to have a deep bite - though I run a very shallow bite on a single hobbed pulley. Also, with said single hobbed pulley, I’ve only had one filament “hogging” incident with my current extruder design, and that was when the machine idled with filament sitting in the hot end for several hours. It was easy to fix.
I’d also check to make sure the hot end is running well. At a good temp, it shouldn’t require much pressure to work well.
you can also try this to cool the extruder down http://tinyurl.com/printrlight1405