Is it necessary to use a thermowell in a HLT or Mash tun when installing a dial thermometer? My thoughts are that it will help protect the thermometer stem from damage if it gets hit with the mash rake or spoon. Would there be any other reason to use a thermowell?
Maybe. But I have Blichmann Brewmometers in my three kettles. No wells. Work great. No problems. Calibrate every time you disassemble/resemble, other than that they are bullet proof.
I use the morebeer made kettles and the fitting for the thermometer is just a 1/2" pipe thread sleeve welded to the kettle. Weldless would work too. Have fun.