Issue with extrusion becoming too thin during print - SOLVED

Hi there,

I'm having trouble. I've been having great results with my printer for about a month and a half. But suddenly I find after about the first 50 or 60mm of the skirt, the extrusion gets too thin to adhere to the bed. I've tried all I can think of, including: changing the print speed of the first layer, cleaning the nozzle, adjusting the first layer height percentage, checking the e steps calibration, cleaning out the whole extruder and hotend. But no change. I was looking for maybe some thing that was hanging up or causing resistance to the filment going in as the nozzle got too far from 0 on each axis but all seems ok. The bed is perfectly level and home is set correctly.

This thing was working perfectly for so long and this. Any insight?
Thanks.

Edited 1 time(s). Last edit at 09/03/2012 12:33PM by Ej.

The bed may be level, but double check that the guide bars for the print head are parallel to the bed.

Thanks. Yes I checked it out and it's all plumb. The nozzle is the correct height from the bed for the first layer across the print, it's the extrusion that is too small to adhere.

Sounds like something is in the way inside your nozzle. If you are printing ABS try cleaning it with acetone. In case of PLA increasing the temperature and extruding at quick speed right into the air sometimes helps to "spit it out".

Yeah that was what I thought. I took the nozzle off and cleaned it with a torch. It looked pretty spotless when I reassembled it. I did not use acetone. I also reamed of out the inner Teflon tube inside the hotend as it was a bit snug but now is good.

Should I try acetone instead of torch? Is there another thing to clean out that I'm over looking?

It's a j-head .35mm.

Is your stepper motor getting realy hot? I have the same problem with me sometimes the extruder blocks and stops extruding. My motor winding are fried so thats the problem.

Also it can be that the e steps are not good.

Charlie's 3D Creations

Charlie

interesting. i haven't noticed the motor getting hot but haven't checked either. i've checked that when i ask pronterface to feed 20mm of filament in, it does indeed do 20. does that answer the question or shall I check another way?

Well, it looks like I figured it out.

I retorched the nozzle, followed by some blasts from an air compressor. I then put it under an antique microscope and looked down the nozzle hole to find a small obstruction. Not sure what it was as everything else burned away clean. So I carefully reamed it out with a very small drill bit and blasted it again with the compressed air.

It seems to be working again. Although I'm realizing that the nozzle may not be exactly .35mm as described when i bought it. But I have no real way to measure it. So I adjusted the setting in Slic3r to .32mm which made a difference but be too much in that direction. I'm continue messing with it.