Extruder gouging filament, run out of ideas

[DavidF]

Wildideas, if you put the speed multiplyer to 300 and extruded say 500 mm does it skip? This is one of my checks I do when I first get ready to print, if it skips I know I may be having a nozzle clog or may need to increase my temps a bit.

[pyrophreek]

what is your default extrusion speed? multiplier just multiplies that. Without knowing your default speed, or what you have it set to it makes it difficult to compare. I usually am able to get up to around 200mm/min before I get skipping.

[Eaglezsoar]

The filament should have an easier time extruding from a .7mm nozzle than from a .5mm
It is possible that what you think is a .7mm nozzle is not, it has happened before.

[Demolishun]

I am seeing this issue almost verbatim. I can print an object that is 4" x 4.5", but when I try to print an 8" x 4.5" object I get all sorts of kickback to the extruder feed. Basically I cannot print larger objects that take up more of the bed. There are no restrictions whatsoever when printing a smaller object that stays toward the center of the bed. I suspect this is related to the bowden tube somehow, but I cannot for the life of me figure out what. The extruder feed matches what it is supposed to be, the filament diameter is correct. All I can think is temperature on the outer edge of the machine? I don't see the thermistor values dropping when it goes to the outer edge.

Should I try to measure the filament tip ID? But why would this only do this on larger footprint prints? I can print my 4"x4.5" object just fine. That print takes 5 hours, and has no extruder feed skipping at all.

Edit:
My nozzle is stock BTW. I believe stock is 0.45 mm?

[pyrophreek]

When you reach the outside of the print area, is your bowden tube getting stretched straight? Maybe you need to increase the length a few inches. If the tube is being pulled in the PTC connectors, it could be pinching the filament slightly, which in combination with a high backpressure in your nozzle could be enough to make the extruder skip. If you can, post a pic of the printer with the nozzle in the center of the build surface, and another with it to the edge.

[Demolishun]

Okay, here are the extension pictures:

Center

Back

Right Front

Left Front

Front Center

The tube does not look like it is too tight in any of those positions. At least to me it does not.

[pyrophreek]

yah, there looks to be plenty of slack. Just an idea. Have you tried printing a test cube positioned near the edge? I wonder if one side tends to fail more often than the others.

[Demolishun]

Okay, something else is wrong. I tried a simple job that worked fine before and it is kicking back. So there is something clogged I think.

[pyrophreek]

try this:
1) Remove the bowden tube and PTC connector (look inside the PTC and make sure the metal ring is still intact I have had this break and a piece of it fall into the nozzle)
2) heat up the nozzle to just under your normal running temp
3) take a small section of filament and manually push it in until it comes out the nozzle
4) turn off the heat to the nozzle
5) when it gets to around 150C or so, pull on the filament. You want to get all of it out, even the bit in the tip
6) if this doesnt work to get all of the filament out, try freezing the nozzle and then pulling out the filament

check the plug you pulled out and you may find what has been plugging your nozzle. I have had a nozzle that worked intermittently work beautifully after doing this. Turned out there was a small piece of aluminum in the tip.

[Demolishun]

I sort of went the route you described. Did get it cleared out. Then tried again and it was not letting me feed faster than 25mm/min or not much faster. So I took an exacto and gently reamed out the tip of the nozzle. Now it seems to run just fine (crossing fingers). I did find a some nasty dust crap in there when I cleaned it out. Also a burnt ring down in there. I think it grabbed dust or something and just got worse over time.

[Eaglezsoar]

I sort of went the route you described. Did get it cleared out. Then tried again and it was not letting me feed faster than 25mm/min or not much faster. So I took an exacto and gently reamed out the tip of the nozzle. Now it seems to run just fine (crossing fingers). I did find a some nasty dust crap in there when I cleaned it out. Also a burnt ring down in there. I think it grabbed dust or something and just got worse over time.

And they call these consumer machines? What consumer is going to know how to do the kinds of things you did? These printers, irregardless of who makes
them, are for tech types, not the normal consumer. You have proven it once again.