Welder on board, power supply advice

[Fence Man]

Well hell. This thread is going to cost me some money.
https://www.zena.net/htdocs/welders/..._2nd.shtml#Top
I'm going to need this ^^^^ for that vvvvv.

[rmlarson1098]

Originally Posted by a64pilot

Isn’t tech remarkable.
Yes it is, but Physics is an unforgiving Mistress.

Years ago, many actually I was a contract welder in the oil patch in Oklahoma, I had an old one ton Chevy with a Lincoln pipeline welder as old as I was on its back. 200 amp machine if I remember. It took the one Ton truck to haul the copper wound generator nicely, a 3/4 Ton would have been overloaded with all the other tools, gas bottles etc.
I was working in a yard in Oklahoma City building drilling rigs, had another welder show up one day with a little Toyota truck with a 300 amp machine in it. It was a Japanese machine, but tiny, yet made more power than my Lincoln, wasn’t nearly as smooth an arc, I think it was a big alternator with diodes, but never mind, it was little, powerful and sipped Diesel where my big ole Lincoln was heavy and it’s flat head Continental engine was fond of gasoline. It looked like I was the fool hauling all that excess weight around.
Well one day we were jetting out a mud tank, that is running huge “jet” rod, 7024 I think. Anyway to run that big rod I would turn my Lincoln wide open and let her go. After running rod for I guess an hour or so, the other guys welder just quit, wouldn’t strike an arc, so we climbed out of the tank to see what had happened to his new machine.
The bed of his truck honest to God had molten aluminum in it, seems his welder had melted its windings.
Well of course he took it back to where he bought it, and was explained what duty cycle meant, seems his little powerful welder could actually deliver 300 amps, for 20% of the time, then it had to rest for 80% of the time. He did not get his money back.
Big ole ancient Lincoln Pipeliners I have seen connected to long sections of frozen pipe and run wide open to thaw pipe, they can be run that way until they run out of fuel.

Reminds me of these little 200 amp small frame alternators. I wonder what their duty cycle is?

Yes, Lincoln rules. Retired now, I've got a little Miller stick/TIG machine at home, that COULD work in the marine environment - with a big enough generator. About the size of a shoe box.
The 'new' Innershield wire from Lincoln (and others) for MIG machines does not require any outside shielding gas. It's flux-cored, and does a decent job. Comes in 10 pound spools, or at least that's what I've used. Might come in smaller rolls. At a certain point wind may effect it - just cover up with a tarp. Preferably non-flammable...
The weld store guy will tell you his wire it'll burn through paint, mud, rust, barnacles, etc. Don't you believe it. It is pretty durable and not TOO fussy, but you will have to clean stuff up with your grinder. Buy a wheel (power) brush for your 4" grinder. They work miracles. Don't use the wheel brush flat like you're grinding, use it on edge. They throw a lot of wires out. Safety glasses required.
And why would anybody spend $200 for a electric welding hood? You can buy a brand new 'passive' (old school) hood that'll do a fine job, and not have issues with the salt air. Use that dinosaur hood for storage - it'll hold your tape measure, gloves, glasses and respirator.
You can do a beautiful job of welding stainless steel with stick. But if you make your welding life easier by using a wire-wheel brush on your grinder, make sure you have a S.S wire wheel for stainless work. Do not use a mild steel brush on Stainless. Ever. And wear those safety glasses.

[john61ct]

Great stuff!

Originally Posted by rmlarson1098

Yes, Lincoln rules. Retired now, I've got a little Miller stick/TIG machine at home, that COULD work in the marine environment - with a big enough generator. About the size of a shoe box.

Link please? How big is big enough?

wrt **aluminum** work only

Please confirm or comment on what I have **read**:

gas welding with flux rods can be OK but only for thin / sheet work

For **structural** aluminum say 1/4"+ thick

is that "shoe box" unit OK?

MIG is fast but harder, wrt aluminum really for repetitive production work only, needs precise setup

stick DC+ / DCEP will do in a pinch, but very hard to get "pretty". DCEN only for thin / sheet, specialist rods.

TIG DC- / DCEN is better and easier than the above if AC isn't available, great for structural / thick with helium if indoors

Both above you need to thoroughly pre-weld clean / de-ox and preheat the work.

TIG AC gives the best / prettiest results for structural / thick work, and is also best for thin stuff like sheet

can balance between EN for penetration and EP for cleaning (some) as you go.

pure argon or helium mix requires being under cover, so how best to handle structural / thick work outside, use flux rods but with which of the above ?

Thanks for your help, others also welcome of course

[Reefmagnet]

Originally Posted by john61ct

Great stuff!

Link please? How big is big enough?

wrt **aluminum** work only

Please confirm or comment on what I have **read**:

gas welding with flux rods can be OK but only for thin / sheet work

For **structural** aluminum say 1/4"+ thick

is that "shoe box" unit OK?

MIG is fast but harder, wrt aluminum really for repetitive production work only, needs precise setup

stick DC+ / DCEP will do in a pinch, but very hard to get "pretty". DCEN only for thin / sheet, specialist rods.

TIG DC- / DCEN is better and easier than the above if AC isn't available, great for structural / thick with helium if indoors

Both above you need to thoroughly pre-weld clean / de-ox and preheat the work.

TIG AC gives the best / prettiest results for structural / thick work, and is also best for thin stuff like sheet

can balance between EN for penetration and EP for cleaning (some) as you go.

pure argon or helium mix requires being under cover, so how best to handle structural / thick work outside, use flux rods but with which of the above ?

Thanks for your help, others also welcome of course

The only real choice for aluminium is AC TIG or MIG. If you don't use a push-pull or spool torch with the MIG you will end up insane in short order. Everything else is only suitable for patch repairs. For outside work, you'd need to work on calm days or otherwise protect the work area from the prevailing breeze. When welding aluminium in general, the golden rule is to prepare the weld area within 20 minutes of welding. This is done by mechanically removing the oxide layer with a stainless steel wire brush and then washing with acetone. The reason for this is that oxide reforms within 20 minutes and can inhibit the ability to create a clean and sound weld.

[Snowpetrel]

Its pretty hard to beat the small modern inverter Dc MMA/tig machines for onboard use. They will run happily off a genset, or any poor AC shore supply. I haven't tried mine off an inverter yet.

With this I can weld most things onboard. I've welded thin stainless pulpits (2mm 316l rods), stanchions, Stainless to mild (309l rods), heavy mild steel parts (E6013 and 6011 rods), and cast iron exhaust manifolds (cast iron rods, pre and post heating). Its a versitile, cheap and compact tool.

Welding aluminium is another story. It can be stick welded with the same DC welder using coated 4043 rods. I haven't found any 5556 flux coated rods for the marine grade alloys but the 4043 would do at a pinch, and is fine on 6061. The flux is heavy and caustic, and can corrode the alloy if its not removed, so it is not ideal for pipework where the flux cannot be removed easily. They burn with a heavy smoke. Not much fun inside.

We repaired an alloy yacht in the falklands with stick aluminium rods. Very messy but AFAIK she is still using the same welded in chainplates 20 years later.

Mig welding alloy requires expensive Argon gas. and a slightly modified mig setup. Tig welding alloy requires very expensive Tig gear (HFAC if my memory is correct). Certainly not a cheap scratch start DC inverter welder with a tig attachment.

Another appoach is battery welders. A simple emergency stick welder can be made from 2x12v batteries in series. The readywelder improves this with a spoolgun Mig that can weld alloy (with the right gasses).

There are also a few cheap modifications to an alternator that can turn it into a decent stick welder.

Plenty of options but by far the simplest, smallest, cheapest and most versatile is an inverter DC stick unit.

https://www.google.com.au/url?sa=t&s...AlabIbeXaFniR1

[rmlarson1098]

Originally Posted by john61ct

What's best but reasonably priced for heavy structural aluminum work?

TIG (heli-arc) will work well, but requires an AC machine with high-frequency and a lot of messing about. A MIG (wire feed) welder with a spool gun is simplest in my experience - the small (6 pound?) spool of aluminum wire sits right on top the gun, providing a smoother wire feed process. Aluminum wire is soft of course, and likes to jam up if the wire spool is at the machine and being 'pushed' through a length of hose. Having the spool atop the gun does add some weight on your arm but it balances out pretty well with a bit of practice. External shielding gas is still required which means having a bottle of argon around - the entire set-up would be difficult onboard unless yo have a super yacht.

[rmlarson1098]

Originally Posted by john61ct

Great stuff!

Link please? How big is big enough?

wrt **aluminum** work only

Please confirm or comment on what I have **read**:

gas welding with flux rods can be OK but only for thin / sheet work

For **structural** aluminum say 1/4"+ thick

is that "shoe box" unit OK?

MIG is fast but harder, wrt aluminum really for repetitive production work only, needs precise setup

stick DC+ / DCEP will do in a pinch, but very hard to get "pretty". DCEN only for thin / sheet, specialist rods.

TIG DC- / DCEN is better and easier than the above if AC isn't available, great for structural / thick with helium if indoors

Both above you need to thoroughly pre-weld clean / de-ox and preheat the work.

TIG AC gives the best / prettiest results for structural / thick work, and is also best for thin stuff like sheet

can balance between EN for penetration and EP for cleaning (some) as you go.

pure argon or helium mix requires being under cover, so how best to handle structural / thick work outside, use flux rods but with which of the above ?

Thanks for your help, others also welcome of course

My Miller Maxstar will run on a 4000 watt generator. It likes a true 20 amps. It's a DC machine, and will run positive polarity for stick welding or negative for TIG/heli-arc simply by switching the electrode-ground cables at the machine. I wouldn't have TIG on the boat as I don't want to carry a argon bottle around.
And I run small stick electrodes - 3/32" 7018 (low hydrogen) and up to 1/8" 6010, both of which run nicely at around 85 amps. with 80 or 85 amps you can weld pretty much any thickness of mild steel, (or corten) just need multiple passes.
My duty cycle with stick electrodes at 80 amps is about 30%. Never had a problem but maybe I'm not in a race...
You can avoid much of this electrical stuff by learning to gas weld, as in oxy/acetylene. It does a decent job on aluminum, too, but the learning curve is substantial and a tech school welding course would be very beneficial. The small, portable oxy/acetylene sets are neat, but use quite a bit of oxygen and you might want a spare bottle. As far as flame cutting steel with it, forget about it. You'll go thru a bottle of oxygen in an hour or less. Probably much less. Use the grinder and wafer wheel or reciprocating saw.
In some ways gas welding is similar to TIG in that manipulation of filler wire and torch is pretty much the same, although gas welding normally is a slower process - and proper preheat of steel or aluminum is critical when welding with gas. Not a factor stick/TIG welding with mild steel unless it's sweater weather.
Again, stainless steel welds beautifully with stick (or TIG) but I don't believe you can gas weld stainless.

[Adelie]

Originally Posted by S/V Alchemy

^^^All this strikes me as good information. It really depends on how complex you want to get before you even get to the questions of power. I can run a Miller stick feed unit from 15A 120 VAC and you can get a lot done with that. But portable and quality isn't cheap. This is a basic wire-feed unit for about $700, for instance, and more comprehensive, flexible welders can be a lot more. This is a nice, really portable unit a welder brought to my steel boat, but again, not cheap. Still, I can see brackets and tabs and pipe welds in my future, and I have enough bank and inverter to work on deck, if not for a long time. This takes a fair bit of research, but it's certainly doable. Even at Christmas.

That first link isn’t to a wire feed machine, it’s a stick machine.

[earthmover]

I am finding this thread to be excellent. So here is a question from a newbie. Is galvanized steel easy to weld?

[Fence Man]

Originally Posted by earthmover

I am finding this thread to be excellent. So here is a question from a newbie. Is galvanized steel easy to weld?

I weld it everyday, and while it's not hard, it can be quite dangerous. Breathing the fumes will eventually make you very sick, so a respirator is a must. Do plenty of research before attempting it, and take proper precautions.

[stainless guy]

Miller dynasty 210dx that way you can run it on 110 when out at sea or on the hook and 220/460 1or three phase at the dock or boatyard
Small at 40lbs
Ac/DC output which means you can weld anything aluminum. Need 220 though and limited to .188" thick if you want good results
Only caveat is it is about $6000 bucks
And yes Tig is not easy to pickup you will either pick it up right away or suck at it for a long time

[john61ct]

Wow, more than the boat 8-)

And 1/4" is a must, even 1/2". Guess I'll just need to rent or find a friendly shop.

Thanks to all for the detailed info.

[stainless guy]

Yeah depending on what your doing unless your going into business or large project most of the time it's easier to get a pro that has all the right stuff already to do it

[john61ct]

Really want to learn to do myself, even if just the rough & ready way.

When I lived in remote Australia, learning to wrench my own repairs, an old guy with a full machine shop mentored me, bit of labour exchange.

Maybe I'll take a night class, start knocking on doors.

[roland stockham]

A note of caution to anyone thinking welding may be a good way to earn money for odd jobs while cruising. Nobody is likely to pay you for a bodge job. A comercial welding apprenticeship is at least 3yrs and I would not trust anyone without some proper certification not just night classes. Happy to do my own bodging and help other cruisers in an emergency but not for money. I help when I can and others help me, that's how the community works.