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Wire feed welding is just another name for MIG welding. The basic idea behind wire feed welding is that you use a welding wire that is continuously fed through a MIG welding gun when you pull the trigger.
This is a continuous welding process. As long as you keep your finger on the trigger and the welding wire touching the base metal, you can wire feed weld all day. There are many different types and brands of welding wire that you can use for many different welding applications.
The most commonly used welding wire is probably an AWS ER70S-6 classification wire. This particular class of wire is used in virtually every welding and fabrication shop for many different types of welds. I highly recommend using a precision layered wound welding wire instead of a randomly wound wire.
A layered spool of wire will wind evenly on the spool from left to right with each layer of wire sitting perfectly next to one another. This makes it much better for feeding the wire as there will be no kinks or kinks in the wire.
Randomly wound wire will literally wind randomly onto the old-fashioned spool. Due to the way the wire winds onto the spool in a random fashion, the wire will cross multiple times. And as the spool begins to fill with wire, every time there is a crossover of wires, a little bend can form in the wire.
These small bends in the wire can affect its feedability, which in turn will affect the overall quality of the weld.
When using a MIG machine or wire feed welding machine, you will also have welding consumables that will need to be replaced periodically. Each MIG welding gun will have a contact tip and a cover or nozzle. And then depending on what brand of welding torch you have, there will also be a gas diffuser or some sort of insulator. Some brands of wire feed welding guns, such as the Bernard range, actually have the gas diffuser integrated with the tip holder.
I’m guessing most home or DIY welders will use what’s called a gasless welding wire. This is also known as flux cored wire. However, be careful because there are two different types of flux-cored welding wires. Well, there are actually a lot more than two, but for general home welding, be sure to get a gasless MIG welding wire that is an E71T-GS.
Now, if you decide to use gasless MIG welding wire, you will have to change the wire feed rolls. The reason for this is because it is a flux cored wire, the wire is not solid all the way through. So because the flux is on the inside of the wire, the wire is very soft.
If you use your standard feed rollers, you’ll find that they have a V-groove shape, which is what you want to use if you’re using solid wire. The problem is if you use the same drive rolls on your softer flux cored wire you will find that the wire gets squashed and this can cause all sorts of wire feeding problems so to solve this problem you need to use the which is called knurling. feed roller. The knurled drive roll has many small teeth in the groove of the drive rolls. These little teeth help grab the softer wires and give them traction and push them through the entire length of the welding gun.
Finally, you will need to use a slightly larger contact tip for when using flux cored wire.
So if the diameter of the wire is, for the sake of argument, 0.9mm, you’ll want to use a 1.0mm contact tip. This will help a lot with smooth feeding of the wire and allow for a better weld.