Before I bought my mig welder, I asked the welders at work what to look for. They all preferred a sleeved gun, and they liked metal feed gears. Stay away from the stuff you see at home improvement stores, unless you won't use it too much. Hobart uses Miller guns on some of their units. I bought a Millermatic 175, but wouldn't hesitate to buy a used unit. It's like buying a used car...see how the guy maintains toys and the overall condition of the machine. I think someone pointed that out elsewhere. I think I paid about 575.00 a few years ago for mine with gauges, a cart, a video, and a roll of flux core wire. You may want to look at "Cyberweld" for almost anything associated with welding. Free shipping in the USA and good prices.

This post has been edited by rpoz-29: Sep 23 2009, 09:01 PM

And I wasn't slighting the Hobart either. For years I figured it would be "good enough".

For exhausts and such stuff its probably OK. But if you start building cages, seat mounts, gussetts ... you know, things you are putting your life in the hands of, well ...

Couple of things that I don't think anybody has mentioned yet . . .

I really don't know how to put it into words, but the sound that the welding process makes is some indication of how well things are going. I think it was one of the weldors in the maintenance dep't where my Dad worked that told me that one.

Acetylene welding with steel wire. If you don't learn a thing or two about welding and the weld puddle from trying this, you probably won't no matter what process you try.


Mostly, my own learning has come in little bits like that. Dad tackwelded plates together in a shipyard during WWII, and an uncle grew up on a farm and had a little buzz-box, so I at least had a little guidance in the beginning. I wouldn't rate myself as a "good welder", although with only a few exceptions (involving metal of dubious weldability), the things I've welded together have stayed that way, including some frame structure weld repair on one of my cars. It's not always pretty, and likely not good enough to get certified with. Adequate, I guess.


Norm

Mitch, you know I love ya brother, but I don't think anyone here should get the impression that a 220v Hobart is only good for welding exhaust... (And I'd say the same thing if I'd only used one and owned something else...though I will admit that I've been eyeballing a larger 250 amp Miller or Lincoln...just because I'm in the mood) I've used several of the 110v welders (Lincoln, Hobart, Craftsman and a 220v Snap On and some others, though I've not had my hands on any of the Miller machines) and the arc control on the larger Hobart machine is as good or better than any machine I've personally ever used. It has enough power to blow holes in 1/4" plate steel, if the person with the torch does their job they'll have complete fusion of anything that goes under the arc.

Yup, there are nicer machines with "soft arc start" and higher duty cycles. That's going to make it a bit nicer to use, but there are many machines currently on the market that are more than capable of doing an excellent job for less than a mortgage payment.

As for me personally, the reduced cost of the Hobart saved me enough money to pay for my used Lincoln Tig. Given the choice of a 210 amp Hobart mig and a 175 amp Lincoln tig, or a $1600 mig... I'd personally buy both of my current machines all over again.

As always, your results may vary and nobody has to agree with me... (IMG:http://www.frrax.com/rrforum/style_emoticons/default/beerchug.gif)


(IMG:http://www.frrax.com/rrforum/style_emoticons/default/bow28.gif)

i bought a Craftsman MIG 110v 5 years ago and it works great and is so practical. i've done about 6 custom exhaust on cars, made a trailer for my Glastron GT150 among other projects. i bought it having never welded before and i just practiced. MIGs are easy!

Well, a lot of welders say that and there is some truth to it. But Adjusting by sound does not make a quality weld. The way your MIG welding process sounds is governed by the mode of transfer. Mode of transfer is governed by 'Welding Procedure Specifications'. A WPS is a process that is proven through destructive and non-destructive testing to be an effective weld process.

So, you can not hear if your weld is good quality, but you can tell what mode of transfer you are using.

In MIG welding there are 4 distinctly different modes of transfer:
I. Short-Circuit Arc Transfer - Sound = Sizzle - The sound comes from continuous short circuiting. You are hearing the sound of electric arcs initiating many times per second consistently. This mode of transfer is not allowed in structural applications. It is best suited for sheet metal 1/8" thick or less.

II. Spray Arc Transfer - Sound = Hiss - The sound is a continuous hiss because the arc never extinguishes. This mode is recognized and acceptable for structural welding applications. You can use this mode for thin sheet metal also, but there will be excessive heat input resulting in warpage, burn through and grayed-out welds.

III. Globular Transfer - Sound = Random Crackling and Popping - This mode has an inconsistent sound because molten balls of filler metal are forming at the end of the electrode in random sizes and dropping to the weld puddle. The arc extinguishes and reinitiates at random times. This mode of transfer is unacceptable in most welding codes and must be proven out if it is going to be used. Globular transfer can be very effective, but you need to be very good in order to overcome the inconsitency that is inherent in this process.

IV. Pulsed-Spray Transfer- Sound = Obnoxious Buzz - The sound comes from an electronic on/off switch that is precisely controlled and adjustable. The arc is intentionally turned on/off in order to minimize excess heat input as well as provide a high level of arc control. Pulsed spray is the most versatile way to MIG weld. You can use it in every application very effectively. Unfortunately, you need to have extensive welding knowledge to take advantage of the full potential of this process. Once you have been taugt how to take advantage of proper pulse equipment, you'll never want to go back to constant voltage.

There is a LOT to learn about MIG welding. It seems simple and most people can make it happen, but when it's time to get serious you need to know your sh!t.


In Stick welding there is only one bad thing you can hear. You can hear when someone is "long-arcing". Holding the electrode to far away from the puddle causes porosity, inconsistency, arc wandering and is unacceptable in many applications. In DC stick welding, you should only hear the crackle of flux burning. In AC stick welding, you will only hear the buzz of alternating current.

In TIG welding you should not hear anything other than a light arc hiss in DC welding or buzzing in AC welding. Any other sound comes from dipping the tungsten into the puddle or stabbing the tungsten with filler rod.

Flux-Core welding only has one acceptable mode of transfer- Spray-Arc Transfer. The sound is a constant hiss just like spray arc in MIG with the addition of random crackling from the flux.

This post has been edited by prockbp: Oct 3 2009, 06:13 AM

Best quote in the entire thread.



offtopic

One of our power plants, building a new supercritical unit, has been using a modified short circuit process for large, heavy wall P91 main steam and reheat lines:

http://www.millerwelds.com/resources/artic...IG-lead-the-way

It's pretty slick, but time will tell. It makes the old timers nervous though.

I'm going to agree with Kevin, there is no reason a properly sized, newer Hobart will keep you from making sound welds on a roll cage. I'd recommend the Hobart Handler 210 for most people. Although if money is available the MM211 or 212 is a better machine, but few people can really justify the 212.

I learned at work, I played with the MIG during lunch and then started using a stick for structural apps and got reasonable at that. I became respectable at MIG after 40 hrs or so of playing and then some guidance from a friend that I worked with that used to do aircraft maintenance/welding. He had told me that I had it pretty well down and was impressed. My horizontal welds were solid and then I tried vertical and overhead... whole other ballgame. Eventually I became proficient there as well. I bought an old machine off a guy I knew that was closing his buisness, it's worked great and I'velearned more, but I wish for a modern machine that will weld more and is smaller.

A little guidance and a good bit of practice is the key. I would love to learn TIG, but it's likely an issue of I have to buy one and then take classes to learn it.

I'm not usual... My first welder purchase was a Lincoln TIG 185, and I'm self taught. It took many hours of practice before I had any welds that looked even somewhat decent. TIG is nice in that you can speed up and slow down as needed (indeed, you can even hold a tiny puddle in one spot for as long as you want). TIG is pretty slow, but for one off kinds of things that doesn't matter much. It has a lot less smoke and splatter than MIG. Safety warning: TIG is much brighter and easier to get sunburned -- 1 or 2 minutes is enough to give you a burn you'll feel for weeks. You also need a special TIG helmet since it is so much brighter. TIG takes 3 limbs (torch hand, dip rod hand, and foot control), so it can be challenging welding in the car.