It has a melting point of ~343, but a glass transition at 185 and only retains its mechanical properties at 250 continuously.

http://www.boedeker.com/peek_p.htm

Thermistors are usually here, but sold out right now. I have several extra if you're in a bind.

http://www.panucatt.com/Azteeg_X3_repra … ax33dp.htm

You've nailed it on the head there. Lots of printers seem to have the peek insulator issue, and
even some premium hot ends use it. There are some alternatives (I think I've seen cermaic,
believe it or not) but they are somewhat less practical.

1.) Skipping steps only on restart - this was because the brass barrel was not tight enough into the PEEK, I think
2.) Occasional missed steps when printing - this was because my filament diameter in slic3r was set to like 1.7x, and my filament was 1.8x. I slowed down the feedrate, and it's not missing steps anymore. Need to do another single wall calibration.

I can see one thread poking out from the thumbnut on the spring tensioner.

Occasionally skipping steps again. Gonna throw this thing out the window soon.

When it skips, is it cutting a divot in the filament?  What kind of pressure setting do you have on the idler bearing?

Qubd offers thermisters a dollar a pop. Should have looked around on the site, you can get basically everything you'd need right from them.

Didn't know I needed another one until now!

Thermistors are usually here, but sold out right now. I have several extra if you're in a bind.

http://www.panucatt.com/Azteeg_X3_repra … ax33dp.htm

What'd they run you? I'd be happy to take one off your hands, shoot me a PM.

http://www.boedeker.com/peek_p.htm

Thermistors are usually here, but sold out right now. I have several extra if you're in a bind.

http://www.panucatt.com/Azteeg_X3_repra … ax33dp.htm

The thermistor is no longer located on the outside of the nozzle. Not even on the outside of the heater block (which would run hotter than the nozzle, by necessity), but buried in the heater block, right up next to the brass barrel. It'd be like wrapping the thermistor inside of the nichrome wire when making the sold style Solidoodle hot ends.

It's quite possible that the thermister is not calibrated well anymore. The batteries in my Fluke are dead, so I can't check it. Anyone know where to get a new one? Everything I've read says they're EPCOS 100k, but there are many models of that.

I tightened the barrel with respect to the PEEK about 2 full turns, took the temperature to 270C, been doing ok so far.

What are you doing..?

If your temp is at 270C you are doing something wrong, and/or have a very poorly calibrated thermistor. 270C is substantially above PEAK's melting point.

Am I missing something? I just came back from running outside so I might have skimmed too much

Also sounds like the filament might be softening above the hot end if you can back it out and then put it back in and it extrudes fine. May be time to try the cold end of the hot end cooling.

I have the thermister in the smaller of the two holes above, perpendicular to the barrel. It won't extrude under about 220C. 220C-250C it extrudes fine once it's gotten going.

If I back the filament all the way out and back in again, it will extrude fine.

Four hot ends? At $60/ each? This is becoming an expensive hobby...