Liner Cooked? J Head IV

I just got a j head IV from hotends.com (nice machine work btw). I am
having serious issues with flow rates with 1.75 pla (actually around
1.63mm). I can only seem to get it up to around 20m/s using a gregs
accessible extruder from 185 to 205 C. Most of the time it is
stripping the pla or if I apply to much tension grinding through the
filament. I can push the filament through by hand but only at a very slow rate.
It isn't exactly a hot knife through butter as I would expect.

I figured these should be good for around 40m/s best on what others are printing?

I have a small 28mm fan attached to the outside of the vents as well running at full
blast to cool it as suggested by the manufacture.

I was just wondering if you can confirm the liner is most likely
fried? or if anyone has any other suggestions?

The printer is running PF 44 with the most recent sprinter on a ramps 1.2 for a Pursa.

Thanks for any advice,
James

Depends on your nozzle diameter, the smaller the nozzle the lower the flow for a given pressure.

.5mm

Edited 1 time(s). Last edit at 01/24/2012 05:30AM by zomie.

You may have a partial block, just had one myself. Take apart the extruder and hot end. The first block I had was in the extruder, the second in the hotend. The former required drilling, the latter I simply forced through filament with as much force as I could and it popped out, though I'm sure there are other ways without drilling. They both stemmed from overheating the filament.

Good Luck