Glue on Hot end

I have an extruder where the thermistor on the hot end has come out and I have had to use a replacement a2 times. To make sure this didn;t happen again I placed glue over the thermistor to keep it in place. The glue I used was Jb weld glue which is said to be resistant up to 500 degrees farenheit. My extruder heats up to 200 C(392 F). I was wondering if this was a good idea or could have adverse effects. So far it has held together pretty well.

jb weld is used in many hot ends. Seems to work fine.

Awesome!
Thanks

Dust is right, JB weld has high enough temp resistance, but note: JB Quick does not.

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My printer: Raptosaur - Large Format Delta - [www.paulwanamaker.wordpress.com]
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Good, I use Holts Firegum, which is resistant up to a staggering 1000ºc.

The nice thing about Firegum is that it 'sets' under the influence of heat. It becomes very hard and fixes the thermistor in place. Just be sure that you isolated the thermistor wires all the way up to the head of the thermistor. I'm not sure, but there might be conductive elements in these high-temp glues.

To be sure I wrapped the hotend with Silicone tape after fixing the thermistor in place with the Holts Firegum. I used Mocap Silicone Extreme tape which also has high temp tolerance and bonds to itself. The bond grows stronger with time, it's actually not a bond, but 'self fusing' silicone, which means that it becomes one. This secured the heating element in place. I have not had any troubles ever since, my machine is running for a complete year now without any special maintenance on the hotend (Merlin hotend at this moment).

Edited 1 time(s). Last edit at 12/01/2014 10:40AM by Ohmarinus.

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http://www.marinusdebeer.nl/

JB Weld's website is down right now so I can't officially confirm it, but last I checked even the high temp JB Weld was only good for 500 F intermittently. It's only rated at 450 F continuous. Now that's fine if you're always under 200 C I'm presuming with PLA. If you use ABS temps can be 220-230 C or higher which you're right at that 450 F continuous limit. I personally prefer muffler putty. Once it's cured your leads will break before the putty gives, but if you ever do need to replace the thermistor it's easy to drill/scrape it out. Plus most of your printer will likely be a puddle of goo before you reach it's temperature limit.