In this instructable you will learn how to make a spot welding machine at home using capacitor bank.This set-up is mind blowing for doing welding in remote areas or even on the way.
Even though many of us already have Electrode welders but they consume too much electricity and the gas fumes are very harmful for lungs.
In this system a 12 volts UPS battery or a laptop charger of 15V O/P will power up the machine.
Step 1: Step 1: Connecting the Capacitors:
Get 3 electrolytic capacitors rated at 250 volts and 10000 microfarad each.Connect them in parallel.
You can also connect the car jump start cables to the tapping point of these capacitors.Stick the capacitors together in one place to some wooden base like I did as you can see in the picture.Take a bridge rectifier and connect the DC output of the rectifier to the respective positive and negative of the capacitor Bank.Attach the rectifier to the wooden board as well. Now take a bulb holder and place it on the wooden board.You will also need a two pin plug that is to be attached to the inverter box as you can see in the picture. So 1 wire from the two pin plug will be connected to one of the AC input terminal of the rectifier and the other wire will be connected to one of the wires of the bulb holder.The other wire of the bulb holder will be connected to the other AC i/p terminal of the rectifier.
Step 2: Completing the Circuit:
Now what you are going to need is a 100 Watt 12 volts to 220 volts inverter. Connect the two pin plug to the output circuit of the inverter and connect a 100 watt bulb to the bulb holder.
Take a multimeter and connect the positive terminal of the metre to the positive terminal of the capacitor Bank and the negative to the negative terminal of the capacitor Bank.Move the pointer to 1000 volts DC and place it somewhere where you can see it.
Now all you should be left with just 4 terminals 2 of which are the jumper cables connected to the capacitors while the other two are the input terminals of the inverter.
Step 3: Connecting Crocodile Clips, Battery & Metals to Be Welded :
Now the jumper car cables come with pre-attached crocodile clips.
Connect one clip to a long wooden stick and the other one to the vise as shown in the pics.
Make sure that the 2 terminals are separate.Take 2 metal pieces to be welded.
Connect one to the vise and the other to the crocodile clip attached to the wooden stick.
Now take your 12 volt 7 Ah UPS battery and connect the positive input terminal of the inverter to the positive red terminal of the battery and the negative input terminal which will be the black one to the black terminal of the battery. Your 100 watt bulb should be glowing brightly.The multimeter display will keep on indicating the voltage value to which the capacitors have been charged that is a bulb luminescence will keep on decreasing with the increase in voltage displayed on your multimeter display until it becomes zero.Keep charging the capacitors at least up to 200 volts.
Step 4: Testing:
After the multi-meter indicates 200V or 200+ volts, wear you eye protection glasses & hold the other end of the stick with you being away from the welding site as far as possible.
Touch the 2 metals together.There should be a loud sound and too many sparks.
You should be able to do welding with it easily.
Perform the same test with other metals too and it should perform great.
So guys, that's all for today's instructable.