Hi, First of all. ABS is printing fine. When I switch to PLA however I get jams constantly, these jams fix themselves when you turn the gear hard enough (with enough torque) by hand, the motor does not have this power unfortunately so it skips steps. When this jam is fixed it takes about 10mm of extruding before the whole thing starts all over again. It's not even possible to print anything with this problem. I already dissasembled the hotend, cleaned and reassembled according to the assembly guide. I also tried seasoning the PLA with oil, this didn't really help anything. My thermistor in marlin is set to 5. My fan spins 100% all the time, I have it hooked up directly to the 12v Power supply. Does anyone know how to fix this? At this point I am very seriously considering to just buy a J-head and I know I'm not the only one with this problem..
Sounds like a filament problem. Is your fan on the hotend constantly on? What is your temperature? Have you tried increasing it? Some Plas like Faberdashery need more heat. Especially problematic is filament with filler, i.e. white and non-translucent types (faberdashery earl grey is the most hideous I've ever come across). Try natural or clear for best results.
Thanks for your reply! I tried two brands of PLA, white from Velleman and "royal blue" from Siridi. I tried both brands at a temperature starting at 190°c up to 210°c, I don't really want to go higher because you can smell its a bit too hot. The strange thing is that I had no problems with PLA when I got it, I think after 2 months or so it started to jam. Sinxce then I only print with ABS which works fine. The fan is hardwired to my 12v power supply.
I made a video of what happens exactly. The nozzle is 205°c, in repetierhost I set it to extrude 100mm. [youtube]Y0kB63Q06eM[/youtube]
For my Taz 210°C is the absolute lowest possible. Are you printing 3 mm? Just give it a try at 230. in the worst case you will have excess oozing. What is a major case of jams for me are little ABS chips produced by the extruder bolt. They then block PLA at 210. Can you feel the jams when manually pushing the filament,? The video looks like the filament has parts that have higher melt temperature and the extrusion rate is so high, that those aren't melting fast enough. Try increasing the temperature by 10-20 deg and see if it helps.
230C is way too hot for PLA, it will start to crystalize and it will block the hotend. If you can smell it, it's too hot. This is bad advice.
