Should I keep or convert my old AC stick welder?

[Will S]

Just home workshop, so I don't do all that much welding. I have a Miller 180 MIG welder, and a really old Craftsman AC stick welder that I bought new in 1980. I haven't used it much lately, although I did some welding with it a few months ago. Problem is, it is an AC only machine. For welding outside, it may be the better that the MIG, but a DC welder would be even better.

For the little I do, should I jusr roll it outside, and maybe find some rods that are more AC friendly, or should I CL it and buy a DC machine, or convert it to DC. I am an experience electrical and electronic tech, so the tech part is no problem, but finding cheaps high amperage diodes might be.

What do you say?

 

[Shield Arc]

You could always use gas less flux core wire in your Mig machine. For what little you weld why mess with converting your AC only machine? Maybe pickup some Hobart 335A 6011. I find it to be childs play to run. I'm fairly new to the welding game myself, but here is what I can do with Hobart's 6011.

 

[R W]

Leave it in the shed, you will use it now and again, remember there has been a lot of welding done with ac machines over the years.

 

[Will S]

OK. That makes sense. I'll keep the old box around, for backup. I had been using some old old "Craftsman" rods that I found in a bench drawer, stick welding some brackets for a blower pulley for my kubota. Got the job done, but I wasn't happy with how much effort it took to get a nice puddle going. Could have been the rods. Or me.

I'll get some 6011's, and try a few to just see how it goes. I do have a 10lb spool of .035 flux core for the MIG, so I guess I can always use that if it's too windy to use the shield gas.

 

[pmsmechanic]

I find Lincoln 7018AC a moderately easy rod to weld with. They are a bit sticky but if you weld with them regular and keep in a bit of practice they work quite well.

 

[lostcause]

getting dc stick would be fine, but i wouldn't get rid of the ac stick until you had its replacement in hand. if you need to weld up some old piece of nasty rusty farm equipment that old ac welder and some 6011 will be far easier than trying to use a wire feed with or without gas. besides, unless your area is really hungry for old welders, there's minimal value on those old craftsman welders. i have what is likely the same machine under the bench as a spare, and i there has been one floating around on craigslist here for $50. it's probably worth nearly that much in scrap and nobody is buying it.

 

[rankrank1]

Keep it and use it as is. You own it and it is paid for. Realistically it is not worth all that much anyway $150 max if you got real lucky, but $100 is more likely. Your Best bet is to simply use AC friendly rods. That machine will burn 6011, 6013, and 7014 will likely run like a dream as 7014 truly loves AC. 7018AC may or may not burn well.

DC is nice, but it is not the huge difference maker everybody makes it out to be (for backyard hacks anyway). In essence DC is about 15% to 17% more efficient than AC. I much prefer DC on less than 50 amps settings as it is more stable on really low settings, but on higher amp settings the difference is less noticeable. I can usually make AC do what I want just as well as DC. Sometimes even prefer AC if metal is magnetized like old farm machinery often is. Now I may have to set the amps 10 to 15 amps higher on AC as compared to DC to do the same work but big deal (85 amps DC will be similar to 100 amps AC).

You will likely use that wire feeder you already have instead of trying to use the sub 50 amp setting on the stick machine. You already have quite a few processes covered with the machines that you already have.

 

[Arc weld]

If you get the flux-core make sure to get the T-11 wire as it can be used for single or multi-pass welds. The T-GS wire is only for single pass. Also make sure to change to straight polarity.

 

[stuckmotor]

I much prefer DC on less than 50 amps settings as it is more stable on really low settings, but on higher amp settings the difference is less noticeable.

Rankrank1,
I interpret your lower than 50 amps statement above, to mean that you prefer to weld thinner material with DC.
I just watched this old GE presentation on AC welding, which makes AC sound like the best thing since sliced bread.
http://m.youtube.com/watch?v=CW7I-ymfINU
The film goes into great detail about how AC counteracts the effects of arc blow. Isn't arc blow what causes me to burn through thin material? Would I be able to weld thinner material with a DC stick welder than my AC machine? I've had burn through problems with both a crank adjustment AC machine made by Miller and a dial set Lincoln tombstone.
Thanks,
Stuck

 

[Reverser]

Keep it and use it as is. You own it and it is paid for. Realistically it is not worth all that much anyway $150 max if you got real lucky, but $100 is more likely. Your Best bet is to simply use AC friendly rods. That machine will burn 6011, 6013, and 7014 will likely run like a dream as 7014 truly loves AC. 7018AC may or may not burn well.

DC is nice, but it is not the huge difference maker everybody makes it out to be (for backyard hacks anyway). In essence DC is about 15% to 17% more efficient than AC. I much prefer DC on less than 50 amps settings as it is more stable on really low settings, but on higher amp settings the difference is less noticeable. I can usually make AC do what I want just as well as DC. Sometimes even prefer AC if metal is magnetized like old farm machinery often is. Now I may have to set the amps 10 to 15 amps higher on AC as compared to DC to do the same work but big deal (85 amps DC will be similar to 100 amps AC).

You will likely use that wire feeder you already have instead of trying to use the sub 50 amp setting on the stick machine. You already have quite a few processes covered with the machines that you already have.

+1
My experience with AC/DC has been pretty much the same as yours.

 

[Shield Arc]

The thought of using AC never crossed my mind until joining these tractor sites. Awhile back I did some side beside comparisons. Vertical up hill open root plates with 6011. The last picture is an overhead weld I made on AC. The sound of the welds being made on AC really got my attention! :shocked:

 

[Gary Fowler]

The problem with some of the old AC machines especially the Lincoln tombstone ones was the big jump between setting (like 20 amps or so). One setting may be too low but jump to the next one and it would be too hot. I had a 225A Lincoln AC only machine back in the 70s and I used it to build 2 large farm trailers to haul cotton. They were 8x40 feet and I built everything on them except the axle stub, tires and rims using that Lincoln machine, 6011 rods and 7018 DC rods. At that time they didn't make AC 7018 and it was a bit of problem to keep them burning as they would arc out for no reason frequently but they did make a strong weld.
I wouldn't get rid of that machine if I were you. Get a few small 1 pound or less packages of 1/8" 6011 and/or some 3/32" 7018 in hermetically sealed packages and keep them on hand for when you need the stick rod machine. I think this should work for about any situation you have to use stick rod in especially since you have the wire feeder machine. Likely the old rods you used were weathered too much to provide a good weld. Fresh rods should do much better

 

[Will S]

Every time I read about all the advantages of DC over AC, I start thinking about getting one. But, I'm just a backyard hack, and an old one at that. So no need to run out and buy more stuff.
Thanks for all your help; this is good info here. :drink:
I will be looking for those 6011's and 7018's when I get back up to the supply house. (hmmm, I wonder of H.D. or Lowes carry them. Thay are a lot closer to me.)

 

[rankrank1]

Rankrank1,
I interpret your lower than 50 amps statement above, to mean that you prefer to weld thinner material with DC.
I just watched this old GE presentation on AC welding, which makes AC sound like the best thing since sliced bread.
http://m.youtube.com/watch?v=CW7I-ymfINU
The film goes into great detail about how AC counteracts the effects of arc blow. Isn't arc blow what causes me to burn through thin material? Would I be able to weld thinner material with a DC stick welder than my AC machine? I've had burn through problems with both a crank adjustment AC machine made by Miller and a dial set Lincoln tombstone.
Thanks,
Stuck

No my statement is just as it reads. At less than 50 amps the perceived difference between AC and DC is going to be more noticeable to the average backyard hack. At above 50 amps the difference is much less noticeable to the average backyard hack like me in regards to accomplishing the needed work done (other than AC does sound different).

Arc blow has nothing to do with burning through metal. Arc blow usually comes from magnetized metal and it makes your arc wander all over instead of where you aim it and yes that happening can cause many issues including burn through. Lots of old farm equipment the metal becomes magnetized so to speak just from the material moving through it all the time in the same direction it can happen in factory equipment, or earthmoving equipment as well (haybalers, pan scrapers, factory conveyors, etc.). AC can possibly counteracts arc blow where DC does not.

Now as to whether you can weld thinner metal with DC arc over AC arc, then that answer is likely slightly. Remember though that stick welding is not typically for metal much thinner than say 1/16" (or 16 gauge) and even then you will need to be pretty darned decent to keep from burning through with stick. Thin metal is the specialty of a mig unit or to a lesser extent even a wire feeder with flux core. Having DC on a stick machine will allow you to switch polarity to help a tad bit with burn through and the arc is more stable at the really low amp settings so it can help a tad bit but again it is not an immense advantage.

What do I mean by switching polarity? The easiest way for me to explain that is to sorta think of it like this:
a) DC electrode + (67% of your power into the rod and 33% into the workpiece) (results in max penetration and how you will run DC the majority of the time).
b) AC There is no polarity on AC as it is continuously switching back and forth (50% of your power into rod and 50% into your workpiece).
c) DC electrode - (33% of your power into rod and 67% into workpiece) (results in least penetration and is seldom used, but it can be handy if you do not have a wire feeder and using something like 6013).

The OP already has a wire feeder so anywhere that you could make an argument that DC might be the most beneficial for him is a mute point as he can simply use his wire feeder there.

 

[Shield Arc]

I use to deal with arc blow on a daily basis, when welding piling. One thing that can happen to make you think you're dealing with arc blow is finger nailing. That is when the welding rod burns off to one side, I've had it so bad for at least half a rod, that I had to point the rod 45-degrees to the plate to get the metal where I wanted it to go.

 

[rankrank1]

Every time I read about all the advantages of DC over AC, I start thinking about getting one. But, I'm just a backyard hack, and an old one at that. So no need to run out and buy more stuff.
Thanks for all your help; this is good info here. :drink:
I will be looking for those 6011's and 7018's when I get back up to the supply house. (hmmm, I wonder of H.D. or Lowes carry them. Thay are a lot closer to me.)

Yes Lowes and Home Depot usually stock Lincoln 6011 and Lincoln 7018AC. Remember though any 7018 can be finicky/difficult to run if it draws moisture. Technically 7018 and 7018AC requires rod oven storage. Make sure you try some 7014. 7014 burns exquisite on AC.

If you have a TSC near you they carry Hobrt rod (I like 6011 from Hobart). Rural King also carries Hobart. Menard's carrys some US Forge (from Messer)rods too that are pretty good but selection is smaller.

Typically any box store that caries any welding supplies will usually stock 6011, 6013, 7014, and 7018AC. Why, almost any welding power source can burn these rods.

 

[Reverser]

The thought of using AC never crossed my mind until joining these tractor sites. Awhile back I did some side beside comparisons. Vertical up hill open root plates with 6011. The last picture is an overhead weld I made on AC. The sound of the welds being made on AC really got my attention! :shocked:

The sound of bacon frying(DC) as opposed to the crackling of a brush fire(AC). :laughing:

Great pic's BTW. Your AC overhead looks much better than I could do with DC.
Always enjoy your pic's.

 

[Shield Arc]

Your AC overhead looks much better than I could do with DC.
Always enjoy your pic's.

Well thank you!:thumbsup: You have to remember now, I've been welding for almost two whole weeks. In time I hope to get better.

 

[stuckmotor]

Rankrank and Shieldarc,
Thank you for clarifying my understanding of arc blow. I'd never even heard of it until I saw the GE film. It seems like arc jump would be a better name for it.

 

[Will S]

Yes, a big Thank You from me too. Learned a lot from the posts to this thread, and the welding forum as well. You have shown me that really nice looking welds can be made with an AC machine, the right rods, and of course, the needed skill-set. Appreciate the help!