Welding requires the use of electricity to melt and join two pieces of metal. There are many sources available that can provide enough power, from regular wall sockets to the battery in your car. Two 12-volt car batteries connected together are capable of producing 24 volts of electricity which is enough power to create an electrical current that can be used to create welds.
The first thing you will need to do is to wire the batteries together. This should be done by placing the batteries side by side next to each other. Next you will need to place a pair of jumper cables from the negative terminal of the first battery to the positive terminal on the second battery. This has formed a connection and you now have 24-volts of power that you can use to weld with. Next you will need to connect another pair of jumper cables onto the positive terminal of the first battery and place the other connection onto the piece of metal that you are going to weld. The last set of jumper cables will be used to connect the negative terminal of the second battery to the handle of your locking pliers. The welding rod you are going to use should be clamped into the jaws of your locking pliers.
Once you have made all of your connections the next thing you need to do is to properly clean the metal that you are going to be welding. Make sure that you remove any dirt, dust or other contaminants from the metal. If there is any paint or rust on the metal you should scrape it away and use a clean rag and brake cleaner to remove any oil or grease that may be on the metal. In order for your weld to be strong you must take the time to ensure that the metal is as clean as possible. Any traces of contaminants can cause weld defects that can affect the integrity of the weld being created.
The final step in the process is to make your weld. Put on your welding helmet and other protective gear and then touch the tip of the welding rod to the metal that you are performing the weld on. You are now ready to perform any of the welds that need to be completed. As with any welding process, you should always follow all of the recommended safety precautions (e.g., make sure you have a proper grounding connection, that you avoid welding near water, and to never weld near fumes or flammable materials).