Why is my Makerfarm no longer extruding?

Yesterday I tried to print a large print and 4 hours into the print it stopped extruding the plastic. I tried to print several things this morning and it always starts to print just fine, but after a few layers it stops pushing out plastic. I've tried to print 3 different things and all 3 have done this. I've pulled the filament out (3mm abs) and snipped the melted piece off, then fed it through and it always seems to take it and extrude just fine, but shortly into each print it seems to be slipping.

I can see that the hobbed bolt is turning and the plastic is in the slot with the grooves to help feed the plastic, but the roller on the spring side isn't moving. I've tried tightening the 2 screws with springs and that didn't change anything, I've also tried loosening them and that didn't do anything either.

What am I missing?

Makerfarm I3, 8" .50mm hot end, heated bed, Ramps 1.4, ABS, 3mm

Edited 1 time(s). Last edit at 12/29/2013 05:40PM by vetteguy112233.

I emailed Colin from Makerfarm and he thought it might be a filament problem, but I have a little bit of the last roll that I used and tried that with the same results. I then remembered I had a few feet of the original roll I got from him and tried that with the same results.

A lot depends on just where the new filament came from. I've had "great deal" filament that would print for an hour or three and then plug up. Fully cleaning the hot end took about the same amount of time. Being stubborn, I repeated the experiment several times.

If it's PLA and a Magma, the temperature settings are a bit tricky.. If it's ABS for both filaments, the new stuff is likely junk. If it's the same junk as I got, you will pull black chunks of junk out of the hot end .....

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The bolts on the extruder clamp should be *tight*. Things do not work as well when you back them off.

The bearing in the clamp should rotate. You can clean things up so it will.

Tearing down the extruder every so often and getting all the crud out of it is a good idea.

A bit of lube here and there will help reduce the wear rate on the various parts

From the nozzle size it sounds like a J-head hot end. I would suspect Filament issues. I have
had cheap stuff that shows that issue (strips easily). You can try putting it into a zip lock bag with
some desiccant sometimes moisture in the filament can cause it to be too soft.