Desoldering Tool

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Introduction: Desoldering Tool

It is a tool for desoldering (multi leg) electronic components with 3 or more pins.
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 1: Can Selection

First find some tin can, like this one from the picture.

Step 2: Can Preparation

Then cut the bottom of the can. Later it will be used as container for melted solder. 1-2cm is sufficient height for container.

Step 3: Construction of Heater

For heater you need heater wire (NiCr). Usualy caled "cekas" od "nichrome". If you don't have any, take some from old heater in blow dryer or heating unit, and wind off 1m of wire. Measure resistance because you will need this information later in construction.
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.
Calculation:

U=30 V
P=100 W
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.

Step 4: Heater Isolation

Finished heater must be somehow isolated from metal housing. I have used ceramic insulators removed from old baking oven heater. If you don't have insulators buy them in repair shop for kitchen appliances.

Step 5: Can Attachment

Can from beginning of text somehow must be attached to housing, for that purpose main is drilled through middle and PCB spacer is attached to can with screw. Plain screw with few nuts can be used.

Step 6: Heater Installation

Heater installed in can slot.

Step 7: Heater Mounting

Heater is pressed to can with grill from PC fan.

Step 8: Legs Mounting

Screws with nuts are used for "legs" of device, and ceramic connection block is mounted to hold outlets of heater.

Step 9: First Run

Desoldering tool connected to power supply, and peaces of solder are melting in can.

Step 10: Tool in Use

On next pictures desoldering proces is shown step by step.

Step 11:

Short video samples of device in use:
Video 1 640x480, 18.7MB
Video 2 320x240, 18MB
Video 3 320x240, 19MB

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    90 Comments

    Thanks for a good instructable! :-)

    I made this,just took a shortcut and placed the can on top of a small propane burner,skipping your heater part. The can melts the tin,but when I tried it yesterday,I did not manage to get any componentes free even after an extended "dip" in the melted tin. Any clues why?

    I placed the part of the bord where the component was on top of and in contact with the molten tin and tried to pull the component off with a plier. No luck even after leaving it there for 10sek ( it was a switch I just tested with,so I didn't care if I killed it..... )

    i think it's totally awesome you made this. Question though, would just a regular stove burner element and a pan work?

    I know lead is not a good thing to have in your system. Isn't that the most dangerous part? "fumes"

    solder is only part lead, you can use lead for this but i wouldn't suggest it. just don't inhale the fumes and you'l be fine (id also recommend you have good ventilation or just go outside).

    Sweet idea! This is how PCB circuits are actually soldered. All of the components are placed on the board, then it skims across a bath of solder to quickly solder up all the components.

    I like how this concept is made into a way to desolder.

    You should use a hot iron, works pretty well.

    I know lead is not a good thing to have in your system. Isn't that the most dangerous part? "fumes"

    Won't the heat kill I.C.'s if you use this to remove them and then plan to reuse them?

    a ic that would burn up from soldering temps probably isnt worth reusing.