MakerGear Forum

I've printed several rolls of various materials since buying my m2 about a year and a half ago without ever a single clog. My favorite has been ESUN PetG and never had any issues with the black or magenta colors

Bought my first roll of white and about half way through it I start getting clogs almost every other print. Except the nozzle doesn't seem to be clogged. The filament gets all bound up near the hole just below the extruder gear. After clearing that I can push filament through the nozzle no problem.

I thought at first I must have the tension screw too tight causing it to deform the filament and making it too large to fit through the hole. Every time I took it apart to clear the clog I noticed the temp sensor was loose and not pushed in all the way...but wasn't sure if that was normal or not and didn't think much of it.

Now today, it stops printing mid print and i notice I'm not getting any temp readings from the sensor.

Do you think it's likely my clogs were actually due to a failing temp sensor causing the nozzle to cool down and jam the filament?

Any suggestions for troubleshooting the issue? Should the sensor have been loose like it was and able to slide in and out?

The sensor shouldn't be loose. There is a set screw on the side of the extruder block. A temp sensor usually don't go bad, unless somehow one of the wires break, then your printer would not print. The temp sensor is made up two different types of metals and is welded together.

KiddingMe wrote:i notice I'm not getting any temp readings from the sensor

Tightening the setscrew holding the thermistor will stabilize the temperature readings, because the thermistor depends on a solid metal-to-metal contact with the hot end.

If that doesn't fix the problem, then order another thermistor. Those fine wires break easily, particularly when you're fiddling with the hot end, and even more so when the thermistor isn't firmly anchored to the block. Repeated motion between the wires and the thermistor will eventually cause problems.

A broken wire produces an under-temperature shutdown, but an intermittent break will generate baffling problems that misdirect your attention elsewhere.

Searching the forums for threads with the keywords "thermistor", "failure", and "broken" will produce enough horror stories to keep you awake at night…

Thanks. Gives me some things to look into.

I looked carefully and only found a sets tew for the heater cartridge. I don't see how my temp sensor is meant to stay in.

http://makergear.wikidot.com/m2-hotend-assembly

I guess there is no set screw for the older extruder. If you have an Multimeter you can check and it should read around 10k resistance around room temp. If you dont get a reading then you know for a fact its open and no good. If you get a infinity reading then its also no good.

Just confirmed it is a bad thermistor. Open circuit. Measured it at the connector near the extruder. Do I have to get it from makergear or is there any good amazon prime replacements?

After looking at the makergear website I've decided I'm just going to buy a v4 upgrade kit and metal motor mount instead.

Anything else you guys/gals recommend I buy while I'm at it? I haven't ever felt the need to upgrade anything as I never had any major issues.

Will I need to mess with settings at all besides re-setting z-height?

Good decision on the upgrades. Only other upgrade might be the fans and dampers for the x/y steppers.

The V4 is a piece of cake to set up. Loosen the screw holding the nozzle, home the Z, put a piece of paper under the V4, drop it to the bed, and tighten the screw. Fine tune the Z axis offset in S3D G-code tab as needed to get your layer one height correct.