Looking for Welder Recommendations for Aluminum

[Northeaster]

Hi Folks,

I did not want to pull the "welding at sea: thread any more off topic. I enjoyed the thread, and appreciate input from experienced welders. My dad is a retired pipefitter.

I am only a hobbist, not a real trained, nor certified welder, but did manage to weld up the 32ft trailer below, which was more of a hobby and learning exercise. As I knew nothing about engineering, I just made it heavy, and added lots of gussets.

I currently only weld steel, and would like to get into welding aluminum, in hopes of possibly building an aluminum cat, starting in a few years.

I have used a small MIG a few years ago, and an AC/DC Miller stick machine, which I used to build the trailer.

I would like to take classes, but can't fit them into my travelling work schedule. I may start to pay some experienced welder for a few private lessons, and then practice a bunch, etc.

I have read that I should likely lean towards a MIG and Spool Gun setup vs a TIG setup, to eventually take on a large project, but am open to advice on this.
Assuming a MIG and spool gun is the best for my application, and knowing that I cannot break the bank, at least at this point, for a top of the line setup, what are some thoughts as to minimum amps, duty cycle, brands, etc?
Would one of the cheaper brands like Eastwood do me OK? Will their spool Gun hold up to use (look a bit cheap in Ebay pictures)?

How about the hobart Handler 190 or 210, which runs about $900 with spool gun included?

Any advice would be appreciated!

[SabreKai]

May I suggest you have a look at this thread, Its about a fellow building a 40 foot boat from aluminum up in Norway. Very interesting thread not only in terms of welding but other aspects as well.


http://weldingweb.com/showthread.php?t=29094

[NeptunesTrident]

Without getting to in depth into the idiosyncrasies of aluminum, your going to need a larger machine for boat building. You will need more amperage than either machine you mention can provide. As opposed to welding steel, aluminum has about 60% of the heat dissipation of steel. Simply put, aluminum conducts heat away from the weld zone faster, so you need higher heat input. We use Miller 350P for aluminum of 1/4" and thicker. It is an inverter pulse machine. We also use the push pull gun. A must for consistant feed on aluminum wire. Aluminum will not change colors like steel, when welding. So expect a learning curve. Fit up is more critical with aluminum and shrinkage can present problems if care is not used. Also, on full pen welds, it is adviseable to use a backing, (they make a tape that can be used), to prevent gas leakage. Also be sure to back gouge the weld down to good metal and reweld.

Aluminum is not hard to weld. Just don't get in a hurry and depending on your structure, keep an eye on how hot the structure heats up.

Without knowing the thickness of the metal, it would be hard for me to recommend a min amperage machine. But 250 amps would be a minimum, I would think. Duty cycle is another thing, but most 60% duty cycle machines would be fine. Spool guns on a project like yours with 1 lb spools would be a real pain. It would require a lot more starts and stops. full size spools would work better.

[Northeaster]

SabreKai - thanks. I have read bout the lapstake aluminum boat, on a few sites. Quite a project.

Neptunes- Great info. Thanks for taking the time to write it.
The design I am looking at (remember this s a few years away) uses 5mm al plate on the hull and a mix of 4 and 5mm on the deck. I have no idea yet as to the thickness of the ribs/ frames, etc.

I guess what I would like to do is buy a new or used machine that can allow me to practice and do small al projects in the next couple of years.
Then, a few years from now, I can look at buying a better/ larger machine that will be capable of the larger boatbuilding job.

Do you have any recommendations, or must-have features in looking for a "beginner" welder setup?

I'll attach a link to the type / design I would like to build. There are about 7 videos on youtube - search for sail palau

SAIL PALAU - YouTube

[NeptunesTrident]

Best feature on a MIG welder for aluminum, in my view, would be a pulse ability. 5mm is close to 1/4 inch, but not quite, so a machine of 250 amps should be ok. But the single most must have is a push pull gun. If you can, stay away from the spool guns. Not that they dont work, but I detest changing the spool every 15 min's.

[Northeaster]

re: push pull over spool gun - understood. But, I would imagine that a good 250+amp machine, with a puch pull gun might run something like $3000+ give or take. That would be OK, when and if I am ready to build the boat. For the meantime, in order to be able to practice welding aluminum, I could put up with changing the smaller spools.


As I will not be boat building for a few years, I can justify a sub $1000 welder now vs trying to justify a $3K + welder now.

Same with duty cycle. For just practicing, and smaller projects, I can likely put up with a smaller duty cylce, in order to save cash now. When ready to really build a boat, I would go for a unit with a high duty cycle.

I would think that having a smaller, lighter unit, as well as a larger more powerful unit would make sense when actually building as there would be many times when dragging the larger unit around would be a pain for a few small welds.

[Boracay]

One of our members had his aluminium CNC cut then employed a very experienced welder to put it together.

Boat seemed to go together overnight. Fastest boat build I've ever heard of. Welding may have cost less than the price of a decent welder.

He's somewhere in Indonesia at the moment, on the boat.

[NeptunesTrident]

Originally Posted by Northeaster

re: push pull over spool gun - understood. But, I would imagine that a good 250+amp machine, with a puch pull gun might run something like $3000+ give or take. That would be OK, when and if I am ready to build the boat. For the meantime, in order to be able to practice welding aluminum, I could put up with changing the smaller spools.


As I will not be boat building for a few years, I can justify a sub $1000 welder now vs trying to justify a $3K + welder now.

Same with duty cycle. For just practicing, and smaller projects, I can likely put up with a smaller duty cylce, in order to save cash now. When ready to really build a boat, I would go for a unit with a high duty cycle.

I would think that having a smaller, lighter unit, as well as a larger more powerful unit would make sense when actually building as there would be many times when dragging the larger unit around would be a pain for a few small welds.

Sure, a smaller welder with a spool gun for just practicing is ok. And it may be that you will need to get into tight places a time or two. For a tight area that requires a good weld, nothing beats a TIG. That may be something you need to consider also. A push pull gun comes in various lengths. I have two that are 15 feet and two that are 25 feet. If I remember correctly, you can get them up to 50 feet. Never used on that long, but the 25 footers work well.

[Northeaster]

Perhaps it would be a better idea for mr to buy a small / medium tig now, for practice, and eventual tight spaces, and then if/ when I go ahead with the boat building, get the proper, large pulse mig unit with a push pull gun?

[NeptunesTrident]

Originally Posted by Northeaster

Perhaps it would be a better idea for mr to buy a small / medium tig now, for practice, and eventual tight spaces, and then if/ when I go ahead with the boat building, get the proper, large pulse mig unit with a push pull gun?

In the larger context of things, a good 200 amp TIG would be a good machine to have. And, worse comes to worse, could be used to weld the entire boat. Welding material under 1/4" thickness, a TIG can be almost as fast as a MIG. For sure, MIG aluminum welds contain more porosity inclusions where as with TIG you can achieve high quality welds. So even though the TIG is slower, it requires that you pay more attention.

If he is not in any hurry, TIG would be the way to go, but may add as much as a month or more to completion time. Pretty much depends on how he wants to go about it. Either, or both would be fine.

[Mr B]

Being in Canada,
Go to a welding supplies store and ask them about a Mig welder.
They are usually run by ex welders and can show you a whole range of machines to work with and will recommend a machine for you,
And more than likely will point you in the right direction for all your information locally,

Building a boat you will need a hand piece with at least 5 metres of cable,
A remote wire feed is even handier as you will be up in the air while building,
That gives you 8 metres from the unit to the wire feeder and another 5 metres to the hand peice,

I have a 240 Volt Lincoln 225 amp with 8 metre remote and 4 metre Hand piece, and it is still too short working on my 40 foot Cat,
I can weld alluminium with ease with it.

240 volt is Australia,
110 volts in USA,
Not sure what you have in Canada.

Keep in mind, you will be 5 or six metres in the air when you get going,
The main unit is too heavy to lift that high, so thats why you get the remote,

They are Professionals in the store and do know what they are talking about,

Good luck with it.

Damn, I said to myself, I wasnt going to say any thing more on this thread,

[Lodesman]

Originally Posted by Northeaster

I currently only weld steel, and would like to get into welding aluminum, in hopes of possibly building an aluminum cat, starting in a few years.

This guy built a 50-foot alloy cat in BC with a MIG set-up. You'll have to dig through the build logs, but he does talk about the equipment: Osram VII Planing and Development

[capngeo]

The MIG and TIG processes are quite different, and require different skill sets. Personally I would want both; MIG for speed where the welds are to be ground or not visible, and TIG for the critical, and high cosmetic welds.

As to amperage, and duty cycle... like cash when buying a yacht.... If you have to ask, you don't have enough!

[s/v Beth]

Originally Posted by capngeo

The MIG and TIG processes are quite different, and require different skill sets. Personally I would want both; MIG for speed where the welds are to be ground or not visible, and TIG for the critical, and high cosmetic welds.

I am learning both TIG and MIG, but will use mostly TIG for my boat parts.