Extruder Problems

I was wondering if anyone had any suggestions as to what has gone wrong with my printer. It was running great up until 2 days ago when, with no changes to the settings, the prints became awful. The mustache ring on the right was printed a few days ago and is fine, while the one on the left is what I'm getting now. I'm running Pronterface and Slic3r using ABS at 230 degrees. Infill and perimeter is at 30 mm/sec. Heated bed and same roll of filament. Any recommendations would be greatly appreciated.

It's very difficult to see anything in those photos. You need to post better photos. This may be an extruder problem as you suspect or a serious communication issue between the host and the printer causing the printer to pause a lot. It may even be a problem with the x or y axis. Hard to tell.

Here's some more pictures. Also, the first layer prints perfectly.

Edited 1 time(s). Last edit at 02/07/2013 09:31PM by Evil Monkey.

I get something like that when I get dust or debris partially blocking the nozzle tip or from cheap filament hitting a thinner section in the supply spool.

Thanks, I will pull it off and run a drill bit through it. Your username also suggests you've had some experiences like this

I'm guessing that the first layer is printed at a lower speed than the rest of the layer.Your filament drive might be slipping at the higher speed after the first layer. Perhaps you're going too fast for your extruder. Check your filament drive (gear) for bits of plastic to confirm. Also, try slowing down the print so that it's printed at the same speed as the first layer.

I drilled out the nozzle and cut the print speed in half. There was no improvement, though I have noticed in the past a bit of ABS in the teeth. Even at half speed the print looked the same as full speed. As a note, I built the extruder using the forum more as a guideline then a direct set of plans. Attached are some pictures. The standoff is made of 0.5 inch diameter by one inch long PTFE cylinder with a 1.75 mm hole drilled in the center. Heating element is a 6.8 Ohm resistor.

Likely your teeth of your hobbled bolt or worm gear is loaded with abs from slippage. This means that you need to slow down your print speed or tighten the grip on the feedstock. Feedstock tension is a little bit of an art, too much and feedstock flattens out of shape and requires more pressure to move thru the circular opening of the hot end.

Clean off your hobbled area and remove all the abs debris from part, then grip it tighter, and slow down speed. Likely what happens is it starts to slip and abs fills the teeth until no more grip of abs happens. To reduce this in the future, lower the stepper power to the e stepper for the extruder. This will prevent slippage as the stepper will stall out when too much back pressure occurs.