How to Built Cheap and Trusty Soldering Gun Out of Old Transformer

The most important tool required for all electrical &electronic producer, hobbyist, enthusiast, repairer, tinkerer is soldering iron & the one they must have. Here is the cheap and easy process to make a soldering gun. There is a lot difference between soldering iron and gun here we are gonna built a soldering gun.

· Soldering gun is heavier than soldering iron.

· Its tip is blunt, of only one shape, weak &fragile.

· Soldering gun is used for electrical purpose rather than electronics, commonly used to solder thicker wire.

· One can also use it in other purpose as electronics if feels comfortable.

· Its main feature is it heats up and cools too quickly like a lamp, when you plug in it starts melting soldering lead (tin).

· It also saves electrical bills.

It is my first instructable so here may be some error & may feel some difficulties just ignore it. I am trying to make error less and much understandable.

Step 1: Step-1 (PARTS)

1. Transformer (T/F) 1

2. Copper wire 14swg stranded or not about 18 inch

3. Copper wire 16-18swg 2-3 inch

4. Sleeve

5. PVC tape/Electrical tape

6. Extension wire/cord

7. Switch 1pc

8. Handle

9. Screws

10. Wire connector/coupler 2pcs

Step 2: Step-2 (Tools)

1. Small hammer

2. Notch plier

3. Plier

4. Wire cutter/ Wire stripper

5. Srew driver

6. Measuring tape/Ruler

7. Soldering set

8. Hot glue gun (Optional)

9. Drill (Optional/needed for handle)

Step 3: Step-3 Start Building

-1st choose a transformer.That may be savaged from old electronics.You can also buy it but I refer savaging some old electronics so did I.

-As the size, capacity and quality is high.Your Gun is much better and it works better. Generally, Transformer found in our surrounding that we need are:-

120v/60hz-12v/24v &

220v/50hz-12v/24v of same frequency

(If you don’t know anything about T/F and feeling difficult to choose it read theory of T/f kept in next step) mine is 220v /50hz-24v&12v. Mine has extra tapping in secondary coil. If T/F with only a secondary output is found it is much better. I will explain all about the theory later in next step.

-Now dissemble transformer part.It consists:-

1. Coils i)Primary ii)Secondary

2. Soft iron core

Gently hit the iron core of T/F by small hammer or plier (all around the surface) and then with screw driver and notch plier start stripping off the the iron strip.

-After all removed there left two coils.Identify seondary coil start peeling off insulation and wires too.Now in the plastic frame wind 12swg cu wire only two no. of turns along with insulating with sleeve and leave about 3-4” wire to both ends which acts as eletrode but its not a electrode as in pic and pill off the insulation that are out of T/F. Use sleeve as insulator because it is heat resistance.Your T/f may heat with high temp..In some case PVC tape is needed to re-insulate coil.

Step 4:

-Start assembling the parts likely how you disassemble it.

-The T/F should be with outer cover so handle can be fixed easily, choose the handle; Make appropriate hole and screw up join and fix handle. (I joined PPR pipe and socket to make handle cuz its easy and strong)

-Insert wire from primary coil to handle make hole for your switch.Solder switch and extension cord, fix the switch and extension cord out from handle. You can use hot glue to fix switch and wire.

-Now the best part cut about 16-18swg of copper wire in piece of 4”.Bend it in the center and make ‘V’ shape with wire connector connect ‘V’ wire to end of our new secondary coil. If you don’t have connector just wound each other but don’t solder. Now the V tip is the tip of our soldering gun. Enjoy the party!!

NOTE-If you want to re modify the iron and use what it was previous don’t disassemble secondary coil.Measure the frame and wound your coil, re-insulate it with PVC tape so it looks like it is in frame and continue. You can now disassemble your iron and place its original secondary coil and use what it was.

-If you want LED glowing make 30-40 turns of your peeled secondary wire (any thin enameled/insulated cu wire) works and place it along with new secondary coil and solder led with a certain resistor.

This can be done in about 2 hour maximum.

Step 5: THEORY About Transformer

A T/f is a static or (or stationary) piece of apparatus by mean of which electric power in one circuit is transformed into electric power of same frequency in another ckt.It can raise or lower the voltage in a circuit but with a corresponding decrease or in increase in current.The physical basis of T/F is mutual induction between two ckts linked by a common magnetic flux. In its simplest from it consist of two inductive coils which are electrically separated but magnetically linked through a path of low reluctance. If one coil is connected to a source of alternating voltage, an alternating flux is setup in laminated core must of which is linked with the other coil in which it produces mutually induced e.m.f. The transformer works under the principle of Faraday’s Law of electromagnetic induction.

(The theory is directly extrated from a text book of electrical technology by B.L.Theraja)

I’ve attached it’s one of the chapter (Transformer) so you can also know briefly about principle, construction, calculation and all about single phase transformer.