I'll chime in on this one. Having worked in the welding field for 40+ years, I'm solidly in the Miller camp. But I have that luxury. Back in the '90's, I had friends that bought some of the cheap welders to work on their cars and stuff, and they were absolute garbage. From what I've seen in recent years however, I think that some of the "lower" quality machines are just fine for doing a LoCost. Running on 120v, and using .023", .030" or .035" wire with gas is not a huge outlay of cash for this type of project. Skip the Starbucks or Dunkin', and bag lunch for a while. It's one of the most important tools for the build. If you have problems with the welder, you have problems with the whole build.
The wire: I've seen the "penetration" thing come up a few times. Think of it like stick. Pipe guys typically run a 6010 root. It's rough, spatters like hell, and all but insures complete penetration of the root. Then they run 7018 for the hot pass and the cap. It has less penetration, but it lays in nice, and doesn't make a mess. With Mig, the same applies. With a given set of parameters, the flux core will typically yield deeper penetration, at the cost of spatter and flux inclusions, and residue that typically needs at least a wire wheel and grinder to clean up. Bare wire will yield a nicer looking weld with less absolute penetration. However, we are typically talking about tubes that are 16ga or 14ga, with brackets occasionally in the 1/8" to 1/4" range. Even the lower end machines are capable of running hot enough, especially with .023" wire to run a bead right on the edge of blowing through, basically full penetration. You will have to watch your duty cycle, however, if you are making longer welds. In all of the fabrication and certification work we do, we have found that the Lincoln L-56 is probably one of, if not the best wire out there for this type of work. It is an ER70s-6 wire, which means it has lots of deoxidizers to help insure a good weld Hobart has a line that is supposed to be as good, but I have not had a chance to test it yet. I have a few spools of L-56 to go through, but I'll try it after that. They also have a line that is made in China, and it sucks. I was talking to Omterry on here about this when he bought his Miller, which came with a roll of the Chinese Hobart wire. His welds were ok, but nothing to write home about. He attributed it to inexperience. One Saturday he ran out of wire mid-weld. He went to the Orange Box store, which in an odd twist actually carries the Lincoln L-56, and bought a 12lb. spool. He called me later that day and sent me some pictures of the welds with the L-56 vs. the Hobart. The new ones were wetted in at the toes much better, the reinforcement was much more even and flat. Less spatter too. One other important note. Buy a bunch of the clip on wire cleaners they have. Keeping dirt and crap out of your wire feed tube, rollers, and liner will go a long way to keeping your welds running smoothly. And blow the machine out once a year or so. Metallic grinding dust does not mix well with electronic boards in welding machines. Ask me how I know. (It was actually a four year old, $5,600 Miller XMT-450 from a VoTech someone gave me because it didn't work. Pulled it apart, and the carnage from the shorts on the boards was staggering)
The machines: As I stated above, I think a lot of the lower end machines out there are up to the task of building a LoCost. That being said, If you think you may be doing more with the machine after the car, I'd pony up for a Miller 211 or better first, or the Lincoln equivalent second. After the initial "Warranty" period, you are going to want to have access to the distributor for parts, consumables, advice, etc. You will have a machine with a better duty cycle and not be struggling with trying to push a machine to do what it was never designed to do.
Hope this helps.
_________________ Dismantalus, Fabricatus, Assemblus..... Certified Welder, Certified Welding Inspector, Full Time Car Freak...In New Jersey no less!
|