lower part of rostock hot end falling down!

[JAY]

I am configuring the Repetier software to the Rostock Max. I am on page 156 of the Rostock Max Assembly Guide where I'm configuring the end stops. After I found the Z axis's end stop screw didn't require any turning, I moved on to the Y axis. I inputted the 'G28' followed by 'G0 Z5 X77.94 Y-45 F3500' and found that my screw needed adjustment. At that moment I started seeing smoke come from the hot end.

As I looked closer where the smoke was coming from and noticed the tip of the hot end (the part that the resistors are in) was falling a bit. I gently touched the copper nozzle with a screw driver and noticed that the tip with the resistors is now loose! I immediately turned the hot end heat off. the tip is now loose from the extractor. What have I done wrong here?

[Polygonhell]

Most likely the thermistor was not in good contact with the aluminum, and as a result was reading low, resulting in you over heating the PEEK portion of the Hotend and it melting.
I really would not take a Hotend up to temperature without first verifying that the thermistor was reading at least mostly accurately at lower temperatures by using a thermocouple.
FWIW I destroyed the first Hotend I ever owned because the thermistor wasn't properly secured and it creeped out during a print.

[JAY]

Just checked and you were right. The way I had the thermistor wires-as it traveled to the Y axis, it stretched the thermistor wires and pulled the thermistor and rtv out of the aluminum hole. Damn.

[JAY]

Well, I overheated the hotend and pushed the tip back into the extruder carefully by lowering the Z axis down and pushing the tip back in, then once I had it pushed back in applied 12V to the fan, cut the heat to the tip off and cooled it. Seems to be working.....

[Eaglezsoar]

You should buy a new piece of the peek plastic. The one you have is not going to last long after
being heated enough to start melting.

[JAY]

Steve with seemecnc.com 2-day shipped me a new Peek under warranty. Good job guys!

[kbob]

Did you import your camera from Australia?

[dsnettleton]

Did you import your camera from Australia?

I got this joke. It cracked me up.