Spool feed welder questions

[scot]

Any of you guys have experience with the little spool feed / shielded gas units that are currently on the market? I'm going to be welding aluminum and need some inputs on these little units?

Hobart has one out for $400 that looks like it would do what I need. Advertised for up to 3/16" aluminum. I'm a decent welder but it's been a while since I worked with aluminum....a bit of practice will be in order.

Any comments on these little machines? Good report? bad reports?

Thanks

[CaptPatrick]

Scot,

I think you'd be terribly disappointed in any welder costing $400 if your intentions are to build your own aluminum tower...

Aluminum is a tremendous heat sink, and welding on schedule 40 pipe, will require a machine with real punch. Wire feed, (MIG), will weld aluminum but the visual quality of the welds will suck big time.

And that's on non-anodized aluminum... Anodized aluminum will out right require a TIG machine with at least an adjustable frequency in order to get past the anodization without pre-grinding.

Aluminum needs to be gas shielded with straight argon and heavier items will need pre-heating to about 250ºF. Using a blast/stop, blast/stop, (like tack welding), technique, with a 50% overlap will give you the best welds. Don't try to run a bead on aluminum without a big machine. Also, weld with a small gap between the two weldments for full penetration.

Br,

Patrick

[Harry Babb]

Scot
Captian Pat pretty much covered all of the bases......ditto to everything he said.

I am a pretty decent welder but building a tower (if that's what's on your mind) is a lot different than table top welding. In my opinion the MIG simply goes to fast to maintain control. I am sure that you know this from building the tower on you Sea Ray.

The problem is that once you start the weld, you will have to rotate all the way around the pipe......you will be on the bottom...on the side...on the top...back on the side....and wind up on the bottom....all in 4" of weld length or less. You will have to start and stop several times and each start is going to yield a nasty look.......plus having to manipulate the cumbersome wire feeder around pipe and in tight places is gonna make you crazy.

I used a TIG torch with a Thumb Control. You will be a contortionist when done with a tower. I have only built a couple of simple towers.....real time consuming....and I intend to build another one one day.

The welding supply houses that rent equipment will most of the time sell their older rental machines at a pretty good price. Another thing to consider is adding a HiFreq box to an AC welding machine. That's a less expensive way to go. If you add a HiFreq box you will not have remote amperage control or the start stop capability. That's the way I started out welding aluminum. The tungsten is energized all the time.....I layed down a many of pound of wire with a Miller 250 Dial Arc and an add on HiFreq box.

I will send you a message about the elbow later this evening. I found the elbows yesterday......they were several layers down from the surface of all of my treasures (Jo Ann calls junk).

Harry

[Carl]

Is that $400 for the Spool gun or $400 for the machine and spool gun?


My advise is test it before you buy it, or at least with the option to return it. As Capt Pat said Alum sucks the heat out of the zone so fast you need to be able to add it quick (AKA - High AMPs, something lacking on a small machine.

I have one and use it once in awhile. For small, quick welds in lighter gauge materail, a MIG Alum Spool Gun is the cats meow. One job comes to mind and that was attaching 3/32" Alum Expanded Metal to a frame. Not the neatest weld, not the quality of a TIG job, but quick. Look at residential Alum railings.

Go a bit heavier, or larger in size with the material and the problem is the MIG machine belches out wire before Alum comes to temp so you crank up the Amps to it's Max to compensate. So now your running at at the Max rating with a 10% Duty Cycle, so you weld for a minute then allow 10 minutes for the machine to cool, recharge or whatever it does and you part gets too cool and you start the cyle all over again. Keep in mind if you still do not have the Amps to get the part hot enough the first part of that welding time is just trying to get the part hot enough for the materail to flow correctly.


I would not rule out the small machines, but make sure you try it on something you expect to be welding and look at the Duty Cycle at that point. Keep in mind it is not just the thickness of the materail but the overall size as well.

[scot]

Thanks for the advice (warning) fom all. The more I investigate, the more I think TIG is the way to go....which ain't cheap to set up.

Capt Pat:

visual quality of the welds will suck big time

That's a given! I intended on dressing the welds and having the assembly powder coated. The intent is to fabricate the tower in 2 sections using the break away pieces. This gets the unit in small enough sections to powder coat, plus I can move the boat on a trailer if I need to.

Option 2: The best thing for me may be to fabricate the tower, "tack" it together with "something" and then take it to a professional that can finish the welding correctly.

Thanks all..

[Brewster Minton]

I have watched Dave Wesler the welder here in Hampton Bays make a tower for me and its not easy at all. To do it right is hard. He does it all day every day and knows many tricks.

[CaptPatrick]

The more I investigate, the more I think TIG is the way to go....which ain't cheap to set up.

Scot,

In my opinion the Miller Dynasty 200DX is the cat's ass! One of my friends in West Palm Beach, (a top notch tower welder), had a Dynasty 300DX and loved it until he borrowed my 200 for a marina job. He came back wanting to trade me his 300 for my 200. No deal...

The 200 has all the bells and whistles that are needed for any aluminum tower, PLUS it is highly portable, (45 lbs), and works off of either 220VAC or 110VAC without changing any wiring. The machine senses the voltage and self corrects for either. You als have the capability to stick weld with it...

I've had mine for going on 4 years and never a problem with the machine.

Miller's site for Dynasty 200DX is http://millerwelds.com/products/tig/dynasty_200_series/

Some of the best online pricing is Cyberweld http://store.cyberweld.com/miactigwedys.html

Most local welding shops will meet online pricing, especially in this economic stage.

Br,

Patrick

[capy]

Capt. Pat,

We have a 200dx these inverters are as you said, slick!!

If you have trouble with heavier gauges of AL try mixing 25-35% Helium in with the argon......

Really helps and preheat is not required.

Doesn't work to good if you are out side though

[scot]

Thanks Patrick,

If I bit the bullet for a TIG set up I'll take yor advice on the Miller.

Brewster..

and its not easy at all.

I watched my top being built on my last boat, your right it's not an easy task.

First purchase is a good hyd bender. Basically top building is pipe fitting craftmanship. I worked as a pipefitter in my youth. Take your time, gather up the right tools, think it through, measure twice...cut once, if it ain't right, start over.

I think building a serious jig platform will be a big help, professional tower builders don't have the time to lay out and construct a full sized platform and jig up their work as they go.

I think the time for me to build the top is before the cap is faired and primed. I don't want to be crawling all over the cap handling 20 ft joints of pipe "after" the paint prep is complete. If I scratch the cap now it's no big deal.

Still thinking that tacking the pieces together and taking the assembly to a pro may be the route for me. The investigation goes on.

Thanks

[Bruce]

Scot,
Unless your just wanting to build it yourself, I gotta believe the cost of the 200, 3k when said and done, a good hyd pipe bender than won't crimp the pipe, another couple of grand your gonna pay someone to do it.

I use a Miller spool gun to do all my engine supports. Welds are thick but clean, no goose eggs. I've also used Pats Tig and other tig machines.

The learning curve on even using a Tig is high on aluminum enough to make the welds look pretty.

While the 200 is a good machine in my opinion, I don't belive its a machine for building a whole tower.

Two brothers I know have their own weld fab and tower shop and I've talked to them at length about the cost of doing it myself vs having them do it.
Not one of their machines they use for getting tower welds pretty and strong costs under 5k.

They have a Dynasty 200 and use it for lite to med repairs because its easy to move.

Pat and I took a welding class at the local College when he decided to build his bike and I wanted to be able to build my own engine supports.

It helped for the basics and just then a whole bunch of time and welding material was used to get decent.

Before you buy, Id take a class at the local tech school, use their equipment and see how you do before spending 4 to 5k on your own stuff.

Those of us who are mechanicaly inclined tend sometimes to over estimate our talents. Welding aluminum with pretty dime overlapped welds is an art that takes years to perfect.

[bob lico]

i have to say bruce has it right. i took a alluminum welding class after taking 3 welding classes to be state certified and local power company certified to work on nuclear power plant . all high voltage yards are built with alluminum beams that carry 69k volts .lets not get into the technical aspects just the fact that in order to " make perfect dimes " you must do this on a every day basis with a 5k machine. personally i was ok but if you had to walk away and come back a month later -forget it!!! i bought a outfit to connect to my lincoln welder for tig with gauges,gas everything. waste of money . the pupose was to tig weld stainless .the marina has tig,mig , and heliarc and we still bring in a outside welder for alluminum tower work trust bruce and i it is a real specialty to make perfect VISUAL welds on anodized alluminum. look at the radar arch in the post on replacing the bow lights . very unique tower , has side plates , center rigger , holes in both legs for wiring , big plate on top with box below to support radar, hail rail all around to grab when accending to bridge. i bent all the pipes and tacked with tig and a pro came and did all welding . by the time i put this together (first one was skewed) i was better off just letting the pro do it!!!

[Rawleigh]

"Those of us who are mechanicaly inclined tend sometimes to over estimate our talents."

Bruce: I am afraid you nailed me with that one!!! LOL! Been there, done that!

[Carl]

Tower huh...

A quick tack may not be as easy as you might think. To tack you still need to get the materiall to temp and with a low amp unit that does not happen too easy. Actually with low amp units I have found you wind up overheating the material causing it to boil and wind up with a contaminated weld which then needs to be ground out. So you actually wind up making more work for the pro instead of saving him time.

[scot]

Bruce:

Those of us who are mechanicaly inclined tend sometimes to over estimate our talents.

I stay away from watch making, forging raw stainless and laths...everythink else is a big new adventure...there are still thousands of things that I haven't ruined yet.

[Harry Babb]

Well my opinion of this situation varies from the general consensus here. It does take a HIGHLY SKILLED welder to layout a STACK OF DIMES....and when they do it like that it is a sight to behold....especially if you have ever tried to do it before.

Just because the welds are not pleasant to the eye does not mean that the tower is not going to meet the owners needs....form fit and function. Scot even said that he intends to have it power coated which will cover up bad looks with a little pre coat grinding.

If you think welding aluminum is a lot more difficult than welding SS or anything else you are absolutely correct but if you have TIG skills adapting to aluminum is doable with a lot of patience. Once you find the "Sweet Spot" things will start looking up and the gratification is worth the pain of the learning curve. The 3 most important things is good fitup, a good fitup and a good fitup.

I built a tower on my old Chaparral using an electricians rigid pipe bender... Northern tool has a hydraulic bender for 250 bucks that will do the job.

As far as the welding machine.....you do have to have the AMPS but I welded the tower in my pic here with an old Dialarc 250 and a HighFreq box add on (don't know a current price). The welds were not prestine but they were not to be ashamed of and they sure filled my needs. Today I use a Miller Syncrowave 250...! ! !Wonderful! ! ! but not portable at all.

I will encourage Scot to go for it.....



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Harry[/img]

[Bruce]

Scot,
My comment on ability wasn't meant for anyone but me. I still get delusions of grandure.

You'll have to determine what kind of welds you'll tolerate on the tower seams. My comments are based on whats standard tower quality.

Beauty is in the eye of the beholder. Not so much the rest of us.

[Carl]

Harry you may be right. I didn't make mine from the ground up, but modified an existing tower from a 25 Mako by splitting it down the middle and adding a few feet to the center to fit my boat. I did it with an Ol Chemetron 300 Welder and my less then adequate Aluminum skills. However, I knew what to expect from both me and my machine going in.

[scot]

Bruce,
No offense taken at all. I typically no my limitations, that's why I'm not considering anodized + TIG. I just constantly under estimate the man hours! I would loose my butt in the marine repair & fabrication business.

I have a local guy that works with me on these type aluminum projects. He uses a spool set up, plenty strong but not so pretty. That's why I'm going to powder coat the assembly, a little grinding, a little filler, a little sanding and the joints should come out monolithic in appearence.

We built this one for my SeaRay. I laid it out, built the glass and he welded the assembly. I truck bed liner coated this frame and I will say if the desired look is black...that stuff is indestructable and provides a fantastic surface for hanging on. 5 years of pounding around in the Gulf and it's good as new. Time to move on to a tower project.

I do appreciate all the inputs, I've dropped the idea of buying the needed equipment, now I just need to fgure out how to tack the assembly together...with my current lack of aluminum skill.



Thanks for the input guys.

[Carl]

So Scot you do know what to expect, go for it!