ARC Welding: AC/DC vs AC?

I am new to welding and hoping to learn enough to make some money on the side. Am currently looking at the Lincoln AC225 but was wondering if I should spend the extra money to get an AC/DC unit. What are the main differences between the two and their applications? Thanks all!

Reply to
DSuperglide
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DC gives a smoother weld with less spatter and allows a wider variety of electrodes.

The general trend on this NG is to tout the need for a DC welder as the only way to go. I'm of the opinion that 90% of the hobbyist /small repair users can get along just fine with the AC only buzzbox. 6011 for repair/rusty/dirty steel and 6013 for nice looking work on new projects (eg Jeep bumpers and similar) will go a long way.

If you are really trying to make some money you will need to be able to run some of the higher strength rods (eg 7018 and similar)as well as out of position where DC is pretty much mandatory.

If you are just starting out, see if you can find a decent used 225 transformer style AC welder. I see them on

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for $50 to $200 on a regular basis. I'd try for the $100 range as a start. The Lincoln 'tombstone' welder is the standard but it has a tapped transformer rather than the moveable shunt transformer (Miller Thunderbolt). Shunt style has a finer amperage adjustment.

Any of these will require a 240 volt 50 amp circuit to be able to run them at full power. The price of copper wire is enough to scare you lately so price out your costs to get a suitable power source. There are ways to 'get by' for less but none of them are really long term satisfactory.

Stick welding is a smoky process, you will want to be able to weld out of the wind and rain but with LOTS of ventilation. I have my welders sitting next to the garage door. In nice weather I weld out on the apron. In cold weather I move a vehicle out, weld there, open the door when I'm finished.

Reply to
RoyJ

I agree with Roy with the exception of needing DC to use the higher strength rods. You can get 7018 rod that will work well on AC. You can also get 7018 rod that will not work well on AC.

Dan

Reply to
dcaster

Lincoln AC225, here, burned a lot of sticks. 5 or 6 years of use....did have an old tombstone, but got tired of moving it around...or when I moved...

xman

Reply to
xmradio

I missed the start of this thread. Perhaps because it was tagged as one of those spam messages and got deleted.

Anyway, somebody wants to know whether I prefer an AC only machine or an AC/DC machine?

The AC machine will cost almost half (half the parts), but I prefer the AC/DC machine if I'm going to spend the money. Mostly because I think a DC weld is a lot nicer than a crackling AC weld. I've also got the option of going DC- or DC+ (positive or reverse polarity) to adjust my penetration.

There are Inverter machines that run DC only. Those are nice, but I like having the ability to run some AC specific rods if the need arises (like stick welding Aluminum in AC mode if I'm in a pinch).

There's my 2 cents!

Reply to
jp2express

Yeah, you don't need DC to do a good job. The rods that an AC only machine can run will serve just about every purpose, although (as has been mentioned) you may find DC a little easier to run vertical and overhead.

If you can find a commercial machine that puts out AC, it's probably a single phase machine. A big ol' 300 amp AC/DC Dialarc is generally a better investment than a 180 amp tombstone- not so much for the greater output capability (you won't need it, at least not for a long time) but in the fact you'll get a much greater duty cycle, better arc and general greater willingness of the machine to help you do good work. And it'll run happily on the 50 amp breaker.

Machines I've used in my shop at various times:

180 amp Hobart buzzbox (good, a little short on duty cycle): 300 amp Hobart AC/DC tig/stick (single phase, great) 300 amp Lincoln DC only tig/stick (3 phase machine, run with phase convertor- great) 600 amp Lincoln DC only, CC/CV (also three phase, on phase convertor, marvelous machine, haven't tried it yet with a wirefeeder) Miller 300 amp AC/DC tig/stick (single phase, excellent) Linde 200 amp variable inductance wire feed power supply, (100% duty cycle, single phase, wonderful machine, can run a T joint on 50 lb. welding rod can material with .035" wire) Miller 500 amp AC only (single phase, jumbo buzzbox- very good) Lincoln 175 squarewave tig/stick (single phase, great tig but a little short on duty cycle, poor stick welder).

I've probably forgotten a few, but all were run on the 50 amp breaker (along with the phase convertor, when required) and I was generally happiest with the commercial machines.

John

Reply to
JohnM

couple? when i went shopping for my welder, the AC-DC was almost double the AC only.

got the AC, only tinker with it, so it fits my needs fine.

as for the other poster, AC sheetmetal welding is possible. not a joy, but i'd go with wirefeed(not fluxcore!) rather than AC-DC

Reply to
Tater

Get the AC/DC. Exactly as it sounds, it gives you two more modes to weld with. With all three, it covers mostly everything. With AC, you are limited. I'm trying to keep it as simple as possible.

I have always been a proponent of buying more machine than you need so you don't outgrow it. If all you can get is a 225, it's a good machine, but spend a couple of extra bucks and get the AC-DC and you won't regret it.

Steve

Reply to
SteveB

"JohnM" wrote

Try AC on thin metal.

Steve

Reply to
SteveB

So, buy two. An AC and a DC. A simple fix.

Steve

Reply to
SteveB

Buy just one -a.c. and make it d.c., too.

Simple!

Reply to
jusme

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