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alesandro
11th December 2012, 01:50 PM
I'm looking to upgrade my welder to something with a bit more versatility - either a Mig or a DC welder. With the Mig I would be just running flux core for steel and an aluminium spool with disposable cylinders for aluminium. But at $80-$90 for flux core and $20-$30 for an aluminium spool plus either renting a cylinder or using disposable cylinders at $38 each it's considerably more expensive than a stick, particularly when I would only weld aluminium once in a blue moon. With a DC I can use normal stick rods and buy a pack of aluminium arc welding rods for around $130. Tigs and Migs were rare in my time, the only time I ever used them was at college. In the workshop we used stick welders predominately and oxy for aluminium, brass, whatever. I haven't worked as a welder for decades now but can still put down a good bead, although I don't think I'd like to try oxywelding aluminium again after all these years. What are your experiences with Mig and DC, pros and cons, costs, etc.

KBs PensNmore
11th December 2012, 06:52 PM
What I like about the MIG, is that you only need one roll of wire to weld most steel types ie. high tensile (semi trailer chassis) down to mild steel, .5mm up to ? depending on the size of the welder. If you are going to be doing structural welding, stay away from the gasless wire as it can lay down porosity. I have seen trailers that were welded with gasless, fall apart, not very good penetration, OK for 1.6 thick metal or car body, but that is all, in my opinion. There are several mixtures of gasses available from straight CO2 (max penetration) to mixtures with Argon plus other gasses in varying proportions.
The only thing against MIG, that I can think of, is that it requires shelter from winds/breezes, leading to porous welds.
Sure, rental is a large annual cost, (I pay fortnightly $10.00) but Speedigas allow you to buy the cylinder. Check out the suppliers of the gas for their rates, rental,they do vary, as do the contents of the cylinder, same size different amounts of gas
With stick, welding rods need to be kept dry, require a large assortment of rods ($$$$$$) to cover the range of the MIG. Require chipping off , welding stubs, (more mess to clean up), loss of welding rod (about 11/2" per rod average). Out of a 5Kg. pack, waste is about 0.5Kg. Money wasted. DAMHIKT
I bought the largest CIG (local service rep.) MIG that I could run off single phase (250amp), with about 8metres of remote head, and 5metre torch.
You might ask why such long lengths, I found that with other MIG's I had, (in business) the leads were always to short to get under/ into where welding was required.
If doing a lot of work in Ally, a MIG with pulse, AC/DC, and a shorter torch lead, or a push/pull is required.
I have done some work with DC (a Miller vertical rocket) noisy, (not nice in a residential area), required 3phase. This was repairing mounting lugs from concrete mixer gearboxes, I don't know how it would go on light Ally.
Kryn

matthew_g
11th December 2012, 07:22 PM
If you are looking to do structual welds or welds where your or others lives are at stake,I would be looking at a stick welder. I have AC stick DC stick AC mig And AC/DC tig. As well as oxy. I love using them all, But they all have their jobs and limitations.
Know exactly what you want to weld and make yourf decision based on that.:2tsup: