Theory behind this project is fairly simple. Dissolved solder in heated container heats all contacts of electronic component placed together with PCB on this tool. All you have to do is remove component from PCB with pliers or with tweezers. So with this device you can easily desolder 25 pin LPT conector from 2 sided PCB.
Original article on my site here
Step 2: Can preparation
Step 3: Construction of heater
Before calculation you must have 2 more parameters . Power and voltage of heater.
Power of my heater is 100W, recommendation is not to go below that because it takes too long to melt down solder after power up.
Voltage must be adapted to power source that you will use. I have laboratory power source with regulation from 0-35V and I have chosen 30V for voltage of my heater.
rt=28,6 Ohm/m (resistance per one meter)
Rt= ? (resistance of heater)
Rt = U2 / P = 302 / 100 = 900 / 100 = 9 Ohma
Length of heater wire
L = Rt / rt = 9 / 28,6 = 0,3m
If you don't want to calculate parameters and you have a power supply with voltage regulation, just take piece of wire, connect it to power supply and rise voltage until wire (heater) gets to red glow. This method can be used for checking the calculated parameters.
On the picture is my heater. Coiled on 3mm drill borer and extended to desired length.