Welding Tips and Tricks

Hello all,
I am new to the forum. I've appreciated the knowledge that gets kicked around here for some time though. I am a marine engineer. I work on the ocean. I have a broad foundation in welding and cutting but I wouldn't claim to be expert level at any process yet. (Maybe I never will, seems easier.) I wanted and needed a new multi process welder for my place. I had harbored ideas of picking up on aluminum welding as well. Mostly for marine applications. I researched and settled on a powermig 350 mp. With it, I bought a lincoln magnum pro AL 225ac push pull gun. This product is manufactured by MK and the python has similar specs. Now I am rolling into a project of building a 16' work skiff soon. Nothing more than 1/8" to 3/16" on the job of 5xxx and 6061 for extrusions. I think the lincoln gun with a duty cycle of 60 at 225a will work for the project I have in mind. On my last trip out to the ocean though I was asked to take on some larger projects. Now I'm thinking I would be better off with a water cooled gun. The same gun, water cooled is a couple hundred more. And for the cost of a cooler the duty is 60% @ 450a. At least then there is nothing much the machine could do to hurt the gun (60% @300). It's an expensive gun. I've heard great arguments in both directions. (From the manufacturer and long time work men.) So, I'd love to hear your opinions on this. I haven't struck an arc with it yet. Pretty easy to swap it out now rather then later. I appreciate your help and willingness to share your knowledge.

Intoeasy wrote:Hello all,
I am new to the forum. I've appreciated the knowledge that gets kicked around here for some time though. I am a marine engineer. I work on the ocean. I have a broad foundation in welding and cutting but I wouldn't claim to be expert level at any process yet. (Maybe I never will, seems easier.) I wanted and needed a new multi process welder for my place. I had harbored ideas of picking up on aluminum welding as well. Mostly for marine applications. I researched and settled on a powermig 350 mp. With it, I bought a lincoln magnum pro AL 225ac push pull gun. This product is manufactured by MK and the python has similar specs. Now I am rolling into a project of building a 16' work skiff soon. Nothing more than 1/8" to 3/16" on the job of 5xxx and 6061 for extrusions. I think the lincoln gun with a duty cycle of 60 at 225a will work for the project I have in mind. On my last trip out to the ocean though I was asked to take on some larger projects. Now I'm thinking I would be better off with a water cooled gun. The same gun, water cooled is a couple hundred more. And for the cost of a cooler the duty is 60% @ 450a. At least then there is nothing much the machine could do to hurt the gun (60% @300). It's an expensive gun. I've heard great arguments in both directions. (From the manufacturer and long time work men.) So, I'd love to hear your opinions on this. I haven't struck an arc with it yet. Pretty easy to swap it out now rather then later. I appreciate your help and willingness to share your knowledge.

I say stick with air cooled.

But that's just my seriously unqualified opinion.

Looks fine to me. I appreciate it.

Intoeasy,
Welcome to the forum! The first question that came to mind is how big are these "bigger projects" as far as weld size, length and material thickness? Second question is how long will this project last? Is it just one piece or project that you will never see again? If so I recommend staying with the gas cooled gun. If you feel this will be a on going thing then maybe the water cooled makes sense. I have a water cooled gun (non-push pull) that I have used on my 350MP and it works great but the water cooler was a pain as well as the extra cords and bulk of the gun.

Seeing that this is an expensive step I would see if you will really exceed the duty cycle of the machine/gun. For your original project is sounds as though the gas cooled unit will be fine for the given material thickness but is you are welding say 3/8" and thicker for long runs I think water cooled could be justified.

I ran your set up a while back on some .100 3003 and never had a problem and some of my runs were 48" at a time but I also had long cool down periods. If this were my decision I think I would agree with AKweldshop and stick with the gas cooled unit.
-Jonathan

Thanks for the information. I haven't even lit up with this machine yet. I was approached about several small projects where I have no equipment conserns. The larger one, finishing out the decks and house of a welded aluminum boat hull constructed of 3/8th plate. The scope of welding is yet to be determined on it. Even the most of that won't be working that thick. I see there not being an issue 99% percent of the time. I don't normally shell our this type of money on tools I don't intend to keep forever. (Never know what the future will bring) Mainly, I wish the duty cycle of the guns matched the machine. I looked at guns built by other manufactures that make the claim they do. They don't plug in and then I learned thru a helpful technician the product doesn't live up to the claim anyway. I am going to run with advice you both have givin me here and go enjoy the machinery I bought. The physical world is always much different then the one on paper. Welding isn't my primary trade either. I can relax a while if things heat up. If it becomes a burden later, I will figure it out then. I appreciate your advise.