This was the scary part so far. I’ve read a lot of people burning up their hotends, usually due to thermistors not mounted properly and falling out, etc.
So what I wanted was to find a glue or epoxy, that’s high-temperature (>300degC) AND it had to be a good thermal conductor.
The stuff exists, but you won’t find it in your local hardware store, and finding a Canadian supplier online was just proving futile.So I opted to go this route.
I have some Arctic Silver. It’s a good thermal conducting compound for mounting Heatsinks to CPU’s, the problem is it’s only rated for about 200degC, because it dries out, and it isn’t a glue. The other stuff I have came with the hot-end itself, and that’s just standard muffler putty. My worry is I have NO data on how well this muffler putty conducts heat.
So what I did was I put some Artic Silver on the inside of the heating resistor and the thermistor, and I used the muffler putty on the outside to hold them both in place. Hopefully the Artic Silver will allow heat to conduct well, and the muffler putty will keep everything in place.
The good news is the thermistor seems to react quickly and well to changes in the blocks temperature. I brought the block up to ~50degC using a 9V battery, before I noticed the battery itself was getting up to about 50degC too and I quickly put an end to that.
J-Head HotEnd