Solved Constant filament "clogging"

After a couple of successful prints, have started experiencing constant rapid "clogging". By that I mean extrusion just stops while printing. There is none of the "clicking" I can normally hear when a jam occurs and the hobbed bolt is grinding and skipping on the filament.

After reading the thread on clogging, realized I had lost the filament oiler so downloaded the linked one. Have been unable to print event that.

Tried drying the filament, tried different filament, same problem. It just seems to stop feeding. and grinds the filament, but not all that much. The roller pressure seems to be adjusted properly

Using a e3d v6 hot end with a 4mm nozzle, a "hard" one as I had been doing a little Carbon Fiber printing. VERY little. I found the silicon boot was collecting filament and had a tear in it. I've ordered a set as well as a hobbed bolt, to replace what is apparently the original. And some new PLA filament.

I can say that after cleaning things up and trying a test extrude via Matter control, the filament does feed, but appears to speed up and slow down during a 100mm feed. A sort of "surge". That is what spurred me to dry the filament to begin with. However, that does not appear to fix the problem just noted.

Sets me to wondering if perhaps the feed rate is simply too high, trying to force more through the nozzle than is really possible. I guess I do not know how to accurately determine what it should be set at. Probably this has been figured out before hand for various nozzle and filament diameters, but I would like to verify.

While I can probably find stuff by searching, there may be a way specific to robo.

 

If you have not yet increased the nozzle temperature, do so by five degree increments and perform the test you reference as the 100 mm feed. If you're getting those surges at the current temperature, it can be due to the volume per unit time not remaining long enough in the nozzle to melt. As the filament is "not-melting," it's slowing enough to get hot, then flowing until it cools too much to flow again.

Consider also to download a temperature test tower and configure the model for your slicer/machine to determine best temperature for that specific brand and color of filament. Look for a temp tower with a tiny cone for each temperature segment, as it will provide indication of stringing. The tower I use also has an overhang section for each segment, allowing one to gauge droop at a given temperature.

 

How important is an oiler? I'm using a bowden tube system on a different printer and only rarely am I applying lubricant. I get clogs from using garbage filament (US$5/kg) but even then lubrication doesn't help.

 

Thanks for the clarification. This brings to mind something I'd read some time ago that all metal hot ends can be "sticky" for PLA.

 

Well, I was clogging with PET G as well as I may have mentioned. One thing that bothers me is that it has become very difficult to get filament started down the (teflon ?) tube that came with the E3D v6 head I put in last year. There does seem to be some friction the first inch or two of travel "down the hole".

At first it was a joy and very easy to get started, mainly as the insertion point was, effectively, much higher in the carriage. Now it has become a struggle and it appears to be a bit "out of round" now. I tried cleaning it out with a small drill bit and wiggling it around, cutting side "up" to reshape it but is did not seem to help.

Oiling did seem to help, but the first print attempt failed to adhere to the bed, probably over oiled. I'm gonna take a break till the parts come in, for one, I hate cleaning melted filament off the hot end and need/want that silicon mask. First time I tried printing without it and what a mess once the print popped off the bed. The old one is torn and I don't trust it at all.

 

When I went there, they suggested this stuff, as "better": Capricorn XS Reduced Friction Bowden Tubing 1.75mm

Well, their auto salesbot suggested it anyway. Any opinion?