DIY Hot Plate Heater Cartridge

[travelman]

Hi! I would like to build the DIY PID Soldering Hot Plate at http://mightyohm.com/blog/2009/01/diy-p ... -hotplate/. I found the McMaster-Carr link and found several 1/2" diameter cartridges with different lengths. What is the length of the cartridge used in the project? If you know what the part number was, that would be great!

[mightyohm]

I used a 4" cartridge. The part number is 3618K377:
CARTRIDGE HEATER, HIGH-TEMP, 120V, 1/2" DIA, 4" LENGTH, 500 WATTS