Teflon tape against leaking hot end?

[dries-bessels 0]

My newly assembled Ultimaker+ is badly leaking rom between the braass pipe and the aluminium heater block. I ordered a new set but am wondering if putting Teflon tape on the brass pipe would diminish the chance of leakage there?

I know it should not leak but I have no idea to make sure it doesn't...

Thanks!

 

[gr5 1,249]

First of all be very careful when rotating these parts now as brass is not nearly as strong as steel.

Only rotate these parts when the heater block is heated to around 180C so that any plastic in there will not act as "loctite". No need to go hotter than 180C as that can turn PLA and ABS into a kind of caramelized glue if you leave it hot for hours but 180C is pretty safe.

Teflon tape is fine. It has a glass temp of around 250C but it should be fine up to even 300C as a thread lock so the answer is "yes".

It may be that you didn't quite assemble it correctly. Your nozzle should not be touching the aluminum - there should be a very tiny gap - maybe 1/2mm such that you know for sure that the brass nozzle is touching the brass threaded pipe.

Years ago (more than 2 years ago), Ultimaker used to supply about 1 meter of ABS filament with the kit. The idea as to initially print with ABS such that the ABS would leak out through the heaterblock and nozzle. This would help clog up any leaks. Then I'm guessing you follow that with some PLA at "low" temperatures - no hotter than 220C I would think. After printing 40 hours of PLA like that the ABS should turn into a kind of glue. But I never had to do this.

If the leak is slow enough, eventually the PLA will cook into a glue and the leak will stop. After 5 or 10 hours of printing.