Why stick welding on ships...

Just watching on cable about the refit of a ocean cruise ship. They were welding everything with stick, even what looked like 3/8" and less plate. Why not MIG? Tradition? Cheaper? ???

I would think it would be easier and cleaner, especially in the tight quarters they were in when welding in the interior of the ship. Wouldn't have to bust slag on the finished welds either.

When they weld the hull plates of a ship, what size rod do they use? Again why not MIG?

I also noticed they loved to use acetylene torches to cut holes in the plates on the side of the ship to add balconies. I know plasma cutters have more and more difficulty with thicker steel, but from a safety perspective I'd think getting a nice, clean cut with minimum heating of adjacent surfaces would be better. They did show starting a fire on board due to some spatter or hot pieces setting some filters on fire.

Just some questions that came to mind. Throughout the management was whining about how slow things were going and I know from my experience if I wanted to weld alot of dirty, corroded decently thick steel I'd fire up a MIG. Just would need a excellent duty cycle power supply.

Thoughts?

Reply to
Bart D. Hull
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So much depends on the geographic area and how people accept change. The shipyards in western Canada went to all position gas shielded flux core in the eighties. Stick welding is convenient when you only have a small amount of welding and you do not want to consume time lugging in a suitcase style wire feeder plus hoses. Welding on contaminated material creates problems with bare wire welding processes and even for some flux core wires. Flame cutting is done with fuel gases rather than acetylene. It is cheaper, safer and gives a cleaner cut than acetylene. Plasma is great on stainless and light gauge materials but on plate it is awkward and there is a limt to the length of your leads. You can run a hundred feet of gas lines to feed a hand torch. Remember also that conflicts between people and some sort of crisis is what film producers want. I am sure there were hundreds in not thousands of film hours that ended up on the cutting room floor simply because everything went right and proper. Randy

Reply to
Randy Zimmerman

Stick welding is very cost effective. The machines are simply and very hard to break. Electrodes are cheap. No gas bottles, hoses or flow gauges.

Stick welding works indoors , with ventilation, and outdoors. You can drag 300 foot leads down through the passages of the ship without having to maneuver a 300 lb welder with a 10 ft gun on it and a gas bottle. Plus with a stick welder you can switch from steel to stainless steel to cast iron by just switching the electrode.

Torch cutting is also fairly cheap. Most yards don't use acetylene for cutting. Propane is by far the most popular choice as a fuel gas. Again the equipment is cheap, simple and rugged.

MIG rules the light-gauge steel and aluminum world. So steel dumpsters and other items made from steel 1/4" and thinner in indoor shops. Aluminum MIG rules the aluminum boat building world.

Plasma cutting is mainly used in small shops for light gauge materials and in large CNC pattern cutter tables.

Reply to
Ernie Leimkuhler

On board ships at sea, or down inside ships, yes, stick rules. On the shipways building new ships, they very often run dualshield MIG. Many ships nowadays are built with steel hulls and aluminum superstructures, and of course the aluminum is all welded with MIG.

GWE

Ernie Leimkuhler wrote:

Reply to
Grant Erwin

"Bart D. Hull" wrote in message news:430569a6$0$2245$ snipped-for-privacy@news.getnet.net... | Just watching on cable about the refit of a ocean cruise | ship. They were welding everything with stick, even what | looked like 3/8" and less plate. Why not MIG? Tradition? | Cheaper? ???

How big a wire can you push through a MIG? Bet it ain't 1/4", and with rods that big, the laydown rate is incredible. They don't use the 14" rods most of us are used to, they're like 19" long or something. Haven't seen one that big in a really long time, but I did burn a couple up in high school. It take some getting used to, since they put so much out so fast. I seem to recall leaning into the rod or something. I want to say there's some 5/16" rod out there but I didn't find it on the web. That doesn't mean they don't exist, since folks that use that size likely buy it by the truckload direct from the manufacturer and internet orders just aren't worth it.

Reply to
carl mciver

I remember the rod they used to use on the flat seams on deck plate. They used these enormous rods with gigantic amperage and welded one pass, and they came out dead flat, the bead about 1" wide. They called it "jet rod" and boy did it stink.

GWE former Boilermaker, shipbuilder for maybe 13 years ...

Reply to
Grant Erwin

Grant, doesn't the greater feed rate on MIG more than make up for the smaller diameter wire? I thought the practical limit on manual deposition was related to welder discomfort at insanely high amperages, not a lack of wire diameter.

Reply to
ATP*

If you really want to lay down large passes there is wire diameters up to

1/16th and the guns are water cooled. I am amazed that anyone would even consider stick welding for anything other than small little jobs. I guess there are still some Fred Flintstone shops around but I cannot see how they can make money. One of the last big jobs with stick I did was on a 100 horsepower blower and motor base. ( 1983) It took forever and we used 3/16 E 7028. Finally the electrode holders got too hot to handle. We had to stick them in a bucket of water to cool them off. Oxy-acetylene will never die and stick welding will never die. They will just slowly fade away. :'))) Randy
Reply to
Randy Zimmerman

It will probably be around for a while for boiler room pipe welding, at least for the root pass. I just acquired an Idealarc 250 and would like to get some stick practice in the next few weeks.

Reply to
ATP*

I don't know. When I worked in the shipyards, I was vastly, immeasurably, less technically aware. Since those days I have earned a Master's degree in electrical engineering and had a 20 year career in the semiconductor/software industry. Funny how things go around, now I'm back in school working on getting my stick welding certification so I can make structural building parts. I will probably get certified in MIG too but I've been stick welding a long time and like Ernie says it's way the cheapest way to weld, and I can make real pretty parts that people like, and the time isn't that big a factor. Yet. When it becomes one, I have a Millermatic 250 which I'm getting acquainted with.

Which makes me have to say something. The prices I see getting thrown around on this NG for welding gear are astronomical compared to what I see on the used market in the Seattle area. I got my MM250, complete, only needed some wire, includes a bottle of C25, for $575. It's basically the same welder as the current 251, but not digital, and it didn't have a spoolgun interface when I bought it (I added the module right away).

Grant

Reply to
Grant Erwin

I would encourage you to also test out on a wire process when you do your SMAW. If you are testing to do structural all you need is a downhand/horizontal test. Just be careful with your stop start on the first pass. That is the most critical part. To give you an idea about numbers and time I counted the number of people in one shop I worked in. There were 12 men feeding two welders. One on the saw, one on the ironworker and ten people fitting beams and columns. Those welders would have never kept up the pace with stick. I notice also that prices have dropped up here in Canada but decent machines are few and far between. Our shop is trying to get rid of a 600 amp Miller with a wire feeder built in the Seventies. They are talking about just getting a hundred Canadian. I have a 250 Millermatic clone that was acquired near new for 1500 Canadian. I have had it for over ten years now. I am sure there are better machines out there but for what little I do in my garage it is perfect. Randy

Reply to
Randy Zimmerman

I'd love to, but SMAW took up the whole summer quarter getting good enough, and I'm still working on the overhead. Maybe, maybe.

Also, I saw a lot of students in this class (Ernie's) whose tuition was being paid for by their employers, working on getting stick certs. On this NG, it seems like it's a MIG world, but at least in the Seattle industrial world SMAW is still very much alive.

GWE

Randy Zimmerman wrote:

Reply to
Grant Erwin

If you can do all positon stick you can qualify for hard wire GMAW. It wouldn't take you a day to practice. An hour practicing welding on a test joint and you would be in the groove. :')) I have to laugh.... The Seattle area the home of high tech and MS. With the new machines Miller and Lincoln are producing they have on board computers integrated into the current and voltage control. I guess it is hard to teach old dogs new tricks. Randy

Reply to
Randy Zimmerman

Used prices are extremely sensitive to the local commercial market. If business is going down, so will the prices. If business is booming, there is usually a fair amount of used equipment out there are mid range prices as the shops upgrade to newer and faster equipment. But if business has been skimpy for several (or many) years, the used market will be bone dry, only high prices and trash (sometimes on the same deal!)

Around here (midwest), used TIG welders are just not to be seen. The hobbist/experimenter market is way larger than the commercial market.

Grant Erw>

Reply to
RoyJ

In the Seattle area there are 4 main employment areas for new welders.

The Boilermakers cover all the steel shipyards, and many of the larger fab shops. They mainly want Dual-Shield and Stick, with occasional TIG for copper nickel piping on ships.

The Ironworkers cover steel building construction. They mainly want inner shield, and possibly stick.

There is a third area made of 3 companies. Genie industries builds manlifts. Capitol Industries builds dumpsters. Pioneer Industries builds metal enclosure boxes. All 3 want MIG, run blazing fast downhill on thin metal. To get an idea of this, set a 250 amp MIG for welding 1/2" steel, single pass, something close to 24 volts, and 450 inches per minute wire. Now set up a 24" vertical, outside corner joint in 1/8" steel. Weld the seam with one constant fast downhill pass. If you so much as THINK about blinking you will blow a hole through the metal.

The 4th industry are the aluminum boat yards. Kwichak is the biggest but there are a few smaller ones. They all use pulsed aluminum MIG, in push-pull guns.

Very few shops have new welding equipment. The aluminum boat yards have the newest stuff for pulsed MIG.

Reply to
Ernie Leimkuhler

The key word you use is "shops", there are a lot of people working outside. And, a lot of work that's still done with stick is non deposition rate dependant, in some work a high deposition rate is detrimental.

JTMcC.

Reply to
JTMcC

- Ernie Leimkuhler - spluttered in news: snipped-for-privacy@news1.west.earthlink.net:

Doggone.

I've often wondered at the way that sort of finish is achieved. It looks like a tig joint, but who in the heck'd do that on a dumpster. Now I know, thanks.

Reply to
Greg M

Anyone in California want a Cybertig 2? there is a plasma welding torch and gas console. with it.

Runs fine. 675 amps, for tig or dc stick. Got all the bells and whistles

Only thing is..its 3 phase. 208-460

Make me an offer . On a cart

Gunner

Reply to
Gunner Asch

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