Once you leave the world of bolt-on parts behind, it's hard to turn back. The one tool that makes it possible is a welder. There are many types of welders that can be used successfully on your Jeep project, but a wire-feed welder is, hands down, the most versatile and easiest to use for a beginning welder-it's as simple as pulling a trigger and pointing the wire in the right direction. After a few hours of practice with a wire machine, even a first-time operator can create a strong, good-looking bead.
The process consists of feeding bare metal filler wire (from a spool of wire mounted inside the machine) through a cable and out of an attached gun. The wire picks up the welding current supplied by the welding power source; this creates an arc between the end of the wire and the metal being welded. The wire functions as a continuously consumable electrode, and the welding machine keeps feeding the wire while the arc keeps melting it.
Compact, 230-volt MIG welders like the Hobart Handler 187 are great for small and midsized projects like bodywork and lighter frame repair. These entry-level welders should be considered the bare minimum for welding on heavy parts such as axlehousings. If you plan on heavy use and lots of thick material, it's best to step into a larger, more-powerful unit with a higher duty cycle and amp rating.
The most popular type of wire welding machine is called an all-in-one welder. These units feature the welding power source, wire-feed mechanism, and gun/cable assembly in one convenient package. All-in-one machines perform the two most common wire welding processes: MIG welding and flux-cored welding. Note that if you plan to MIG-weld, you need a machine with a gas valve.
MIG stands for metal inert gas. The inert gas reference comes from the shielding gas-typically, CO2 or an argon/CO2 blend-that protects the molten weld pool from being contaminated by the atmosphere (oxygen + steel = rust; even miniscule amounts of hydrogen inside a weld can cause cracking). This is the preferred welder for the typical garage, shop, or Jeep welder.
Rather than a solid wire, flux-cored welding uses a tubular wire with flux inside. The most common type of flux-cored wires used for home or farm fabrication and repair are self-shielded wires that protect the molten weld pool by themselves (some flux-cored wires also require a shielding gas). Flux-core welding is really better suited to outdoor work, where the shielding gas could blow away. It's also preferred for field repairs because it works well on rusty or dirty material and because of its portability. In most cases, there's no gas bottle to haul around.
Some of the lower-cost wire-feed welders are flux-core only. If you go this route, make sure the manufacturer offers a gas (MIG) upgrade kit that includes a gas-solenoid valve, a gas regulator, and a gas hose. However, you'll be better off if you choose a wire-feed welder that comes complete with these components.
Between its MIG and flux-cored capabilities, a wire welder can perform any task a stick welder can-and do it more efficiently. To weld different types of metal, simply change the type of wire you're using to match the metal you plan to weld. Flux-cored wires, or those made from steel, run very smoothly through an all-in-one machine. These units can also run aluminum wire through their regular gun. If you plan to weld a lot of aluminum, choose a wire welder that can incorporate a spool gun, a type of hand-held wire feeder that's designed specifically to feed the aluminum wire.
When picking your first welder, it's best to stick with the big three welding equipment manufacturers in the USA: Hobart, Lincoln, and Miller (or a co-branded version of any of them); avoid cheap import welders. Substandard quality, inconsistent power output, poor durability, and lack of part availability are all good reasons to steer clear of the overseas metal burners. The big three tend to design and market their equipment according to arc performance and quality and have been at the forefront of the welding industry's development. The low-cost imports tend to position their products with cost as the primary focal point.
There are a lot of numbers presented to the potential buyer, and they can be left trying to decipher which number will provide the best value. The critical number is the actual machine rating, which tells the user how much output can be produced by the machine and for what period of time while remaining within safe thermal operating limits of its insulation class. The output is represented in voltage and amperage (for example: 21.5 volts at 130 amps for a Hobart Handler 187).