"Pop" during PID calibration [SOLVED]

[rhoded]

I completed my build and I was able to get it to talk to the computer just fine. I think I didn't wait for the hot end temperature to decrease all the way to room temp before starting the test, then I got a bunch of smoke and a "pop" when doing the test before I turned it off. When it cooled, I took a look at the wiring and everything looked good except the thermistor had come out of its housing in the hot end, would that have been my pop? How else might I check whether I damaged the hot end or not? Should I look for discoloration or anything? The temperature didn't rise above 200°C when I was testing (at most 190°C). I have my thermistor curing with the copper RTV stuff again. Thanks for any help!

[Mac The Knife]

The "pop" you were was probably just an air bubble popping. in your case it was behind the thermistor and popped it out of its hole. The smoke and popping is a normal occurrence when you first fire up a SeeMeCNC hotend.

[JFettig]

When it happened to me it was just an air bubble in the RTV popping. Check the resistance across both resistors together, IIRC its around 6 ohms but you might have to search around to find the actual value.

[rhoded]

Thanks guys, that puts my fears to bed. However, I'm having another problem now but I'm going to post it as a new thread.

[rhoded]

Just a follow-up: The problem has been fixed. What I think happened is that the "pop" was the thermistor popping out of the hot end. My thermistor leads ended up breaking and I had to get replacements. After installing a new thermistor with copper RTV, it worked perfectly.

[Eaglezsoar]

Just a follow-up: The problem has been fixed. What I think happened is that the "pop" was the thermistor popping out of the hot end. My thermistor leads ended up breaking and I had to get replacements. After installing a new thermistor with copper RTV, it worked perfectly.

You may want to check out the threaded thermistors on Ebay, they screw into a 3mm threaded hole and ends all the frustrations with the thermistor
popping out. Here is a link to the threaded thermistors: http://www.ebay.com/itm/Modular-Screw-o ... Fzig4moskw
and here: http://www.ebay.com/itm/Screw-In-Thermi ... SwPgxVPWlV
You will also need a 3mm bottoming tap.