M2 gear cutting filament

[lycat2008]

Using MakerGear M2,Why the gear to push the filament into the heater keeps on cutting the filament and cause the filament to break? Any solutions?

[Tim]

The first solution to this is to loosen the tensioner bolt. Unfortunately there's not much more than rule-of-thumb guides for how tight it should be, but if the gear is cutting into the filament enough to make it break, then it's too tight. It should not need much pressure on the filament, although that varies by the type of plastic. I usually have mine tight enough to leave no more than shallow marks on the filament.

Second solution is to make sure you have top-quality filament. The PLA that MakerGear sells is good stuff, but if you buy cheap stuff you might end up with something that is more brittle than it should be.

Third solution is to print rsilver's extruder mount, which has a place for the filament tube to fit snugly, so that the filament is always going straight in and is never under stress. Make sure that there are no pinch points along the filament path, or you may be over-stressing your filament before it even reaches the gear.

Those solutions are more or less in the order of likelihood to solve the problem.

[lycat2008]

Thanks for your suggestions,but for point one that the tensioner bolt is nearly with any pressure,and for the second that we have used this filement to print several models,maybe we can do something following the third point.

[Tim]

With almost no tension on the tensioner bolt, the gear should be slipping, not cutting deep into the filament. That suggests that the printed filament drive may be warped or may not have printed quite right, and is holding the filament too close to the gear, even when there is no tension on the bolt. You could try wedging something into the slot between the filament entry point and the gear, to make the slot wider.

[jsc]

Where does the break occur? At the gear? What does the filament look like after the break?

[lycat2008]

We remove the heater away the gear and let filament go through the slot by hand,that it can work fine.Then we assemble the heater on the gear,the filament can be out of heater for a limited period of time,with a rough draw showing the cut of filament and fuse filament section,see the picture.

the cut.jpg (61.21 KiB) Viewed 10346 times

[lycat2008]

the scrap.jpg (34.03 KiB) Viewed 10345 times

[jimc]

ok so the filament isnt actually breaking, the gear is stripping out on the filament. this happens for a few reasons. one can be the temp is too low. a second is that the extruder is clogged or getting tight. the extruder can get tight or clogged from poor filament or switching plastic types often. in any case, unless its temp related then its probably time to do a hot end cleaning.

[lycat2008]

M2 can run well now~! Tks.