Amps should be close for any type of 7018 but set the amps so you get the proper weld. The dial on the machine is just indicator, run some beads on some scrap and set the amps where you like them. Even experienced welders will do this if they aren't familiar with a specific machine.

 

I have found when welding 7018 ac with ac current i have to be 10 to 20 amps hotter going of my poor memory.

 

burn a rod in one go down to 2" at the amps where when you stop rod is dull red hot flux and all, thats rod max amps and usually you use less amps depending on other conditions
1/8" 7018 thats about 150 amps, some flux has more iron powder, etc where max might be 155 or 160 amps, but machine dial is rarely calibrated
.
dial could say you are at 300 amps but obviously not if you can burn a whole 1/8" 7018 rod in one go and its not hotter than red hot, rod be totally melted before you got 1/3 of rod burned at 300 amps

 

I’ve been finding I’ve basically had to ignore the recommended amperage on the package. Using 3/32 rod I’ve had to plug into 110 amps. No matter how hard I try though, it seems no rods do well until striking arcs a numbing of times til the rod is hot, regardless of the type, except nickel rods

 

My welder has no dial, it’s a 180 amp welder that just has multiple spots to plug into. It’s a very old forney C5

 

So let me understand this...you want to know the difference between the amperage for 7018 on DC vs. AC but you can't control the amperage to know where it's set anyway... :dizzy:

Did you compare the resulting bead? I mean, you do have the machine right? Or is it at your friends house???

 

It is generally harder to strike and maintain an arc on an AC machine. 110 amps is a little hot for 3/32" but who knows how accurate that really is. You set your heat by how the rod burns not by what some indicator says. You should be able to set your heat with no numbers at all on the machine.

 

some machines have low arc voltage so arc harder to start and maintain,
.
some machines when arc length is shorter the amps goes up, some machines have arc force control so can turn arc force down.
if burning holes through you dont usually want amps to go way higher with shorter arc length
.
obviously if filling a gap having amps go way higher with shorter arc length is not good. 6011 you can vary arc length for some amp control while welding,
usually 7018 you use short arc length once arc started, usually takes less than 1 second for arc to stabilize on arc start unless you got arc voltage
problems. cheaper welding machines often have low arc voltage problems
.
old industrial welding machines its not unusual to be able to pull a 3/8" arc length, some modern inverters are specifically made so you cannot
pull a long arc more than 1 second to prevent somebody using too long a arc. not all welding machines weld the same
.
usually AC welders are either the cheap low voltage type or big massive industrial welding machines where you might be welding with
3/16" or bigger rod all day long at 200 or more amps

 

My welder had multiple plugs for the amperage, for the ground there’s a low and high plug, then there’s 8 plugs for the electrode cable, each one is a different amperage. This is a 70 year old farm welder, very heavy, a buzz box

 

I’m very surprised that it seems few people know how a Forney C5 operates, ask any farmer and they know exactly what they are, even when I never tried welding, I knew about them. Also, I am a hobby welder, everything I am learning is trial and error, my father died before he could teach me. I never went to school for it, I am just eager to learn, because I am enjoying it. The only way I can learn is by asking advice

 

I’m very surprised that it seems few people know how a Forney C5 operates

But you don't know, why would you expect other people that most likely don't have the welder to know that?

ask any farmer and they know exactly what they are, even when I never tried welding, I knew about them.

So you know about them but just don't know how they operate?

Seems pretty simple, go ask any farmer, there's a lot of them all around the world.

 

Plus, forney makes 2 different rods, E7018 and E7018AC. I have been wondering what the difference in the flux makeup is

 

No disrespect intended. But you're asking the wrong question. Yes 7018AC should be "easier" to run because the AC-designated stuff has some kind of stabilizer-content in the flux to make it run smoother on lower arc-voltage machines. What you should be doing, is reading the puddle. You need to see the puddle: it's size, orientation, shape at the front and shape at the back, it's height. Just like many others will say: Forget the dial and the numbers. You need to make the rod create the correct puddle (which encompasses those characteristics I mentioned, IMO) that you need. If you don't know what you need to see in the puddle, then it's easy with the availability of YouTube videos, but not just any videos. Watch the stick welding videos from Welding Tips & Tricks. Watch them all. All of them. If you can't see what he is making the rod do to make the puddle he wants/needs, then you need to watch them again.

 

AC vs DC coatings

https://www.lincolnelectric.com/en-...ded#:~:text=While E6011 electrodes can be,high cellulose potassium type coating.

https://www.lincolnelectric.com/ass...nsumable_StickElectrodes-MildandLowAlloySteels-Lincoln-Lincoln7018AC/c21026.pdf



In general (and in at least North America), DC is the preferred polarity with all electrodes. However, there are a few situations where AC polarity is used.
The first, most common situation is when you have no choice. This is because you are using a power source with AC output only.
This is typical with low cost, entry-level type welding machines, often referred to as a “buzz box” welder.
A few common electrodes used with these small welders include E6011, E6013 and special “E7018 AC” types.


Possible this is the manual for your welder ?


Search Results
Web results

Manual - Forney Industrieswww.forneyind.com › Admin › Public › DWSDownload
PDF
In 1958 a Combination Welder and Battery Charger Model was added to the C-5 Series of standard model welders which were then in production. The ...

https://www.forneyind.com/Admin/Pub.../Forney/Resources/Heritage+resources/F-and-C-Model-AC-Welder-Service-Manual.pdf



Hope it helps.

 

A lot of AC machines have low open circuit voltage not low arc voltage. If you look at some of the AC 7018 it will mention for use low open circuit voltage machines. You just need to practice maintaining an arc more.

 

Well, you gots an AC machine there.

7018AC (the only rod you should run with this machine......I'll explain later) runs at about 135amps for a 1/8 rod. Keep it shoved into the metal, or it will run porous. You should almost feel the flux coating drag on the steel.

Why run AC rod hotter? The AC version of 7018 has less "dig". It needs to run hot to get good fusion (A DC rod generally has better dig at lower amps)

Why run AC rod at all? Yeah, you can sorta run a DC rod on an AC machine, but it generally runs like crap. AC rods have special arc stabilizers in the flux coating. AC current fluctuates, and needs to have special coatings to tame the back/forth current.

AC rod will run nice, once you get used to it.

I especially like it for avoiding arc blow as here. The plate hanging over the edge of the tubing makes for arc blow (It's all about geometry of the joint, and material) The inside of the "ears" is a very bad place for DC...……..look close, and you'll see a nice clean weld in there...…..a very bad area for running DC.

It's also my favorite for running a lot of short welds in sequence because it restrikes so easy.

 

7018AC some brands flux seems more fluid and I could see maybe slightly higher amps so arc force and increased travel speed keep flux from getting in front of puddle. also AC compared to DC some would use slightly higher amps
.
AC is preferred over DC when over 175 amps cause AC has less arc blow. some structural steel arc blow is so bad you have to lean rod at more of a angle as needed to compensate
.
most people not welding with 3/16" or bigger rod, 98% welding done with 3/32 and 1/8" rod. maybe use 5/32 rod if need 1/2" or bigger welds. sure small cheap AC welder you can get by with doing occasional small jobs like done on a farm. AC not as smooth a arc but occasional job it doesnt matter much

 

E7018 AC mild steel "Low Hydrogen" welding rods easily produce quality results on smaller amperage AC/DC welders. It is suitable for all positions on hardenable steels where no pre-heat is used and on cold rolled steels normally exhibiting excessive porosity when welded with conventional rod. The low hydrogen content reduces cracking and peeling of the weld material. Features excellent restart capability. Designed for welding low, medium and high carbon steels as well as some higher strength low alloy steel. For frames, trailer hitches and chassis.

Recommended Polarity: AC, DCEN, DCEP (Either Polarity)
Diameter (Inches): 1/8"
Weight Lbs. (Kg): 10 (4.53)
Tensile Strength (PSI): 84,000
Amperage: 100-140

Product Specifications:
Recommended Polarity: AC, DCEN, DCEP (Either Polarity)
Diameter (Inches): 3/32"
Weight Lbs. (Kg): 5 (2.26)
Tensile Strength (PSI): 84,000
Amperage: 65-100



Safety Data Sheet
https://www.forneyind.com/Admin/Pub.../DWSDownload.aspx?File=/Files/Files/Forney/Resources/SDS/SDS-Mild-Steel-Rod.pdf


Note : SDS should be provided with every package of welding rod you recieve. The one I have provided a link for should be the same one you were provided upon purchase.
the major difference on the listings are Titanium dioxide, and Calcium Flouride. 7018 and 7018AC are listed together so it is difficult to distinguish which component provides arc stabilization. I'm sure someone at the 800 number listed could provide you with specifics




Forney C-5 multi Tap welder, instead of selector switches has multiple taps like old telephone swithcboard.

Does your unit still have the tap information visible on the front of the machine?There are plenty of picture of these welders on the web if you need that info. The manual I posted a link for covers several different models, and seems to have an extensive troubleshooting section.

Pictures are always helpful.


Also one last thing, if your primary voltage is a little lower(like 208v) instead of 230-240v you may have to go a tap or two higher to get a good weld. Some welders allow you to wire for this specifically. I didn't read the whole manual , but this one might.

Hope you found something that will help you .

 

Hello, I happen to have the same machine at home and it works pretty good for my requirements at home. I've had the same issue running standard 7018 on this machine. When I switch to AC 7018 I get a lot better results, it's still splatters quite a bit but that's normal for AC. It seems that when I switch to 3/32 DC 7018 I can hold and run a very nice bead, hard to tell the difference between AC and DC at that point, but it seems to struggle with a 1/8 diameter rods. I have experimented with different brands of Rod, and the worst seems to be Lincoln Excalibur, which even on DC I think are crap. My go to rod for DC 7018 is Esab AtomArc , or if I can find it some old McKay Rod or Murex . I don't ask what's in that old rod and it's probably not very healthy but it sure does well nice! The DC Rod that seems to work the best for me is 1 made by Washington alloys. And the best AC version I've used so far is the one from Hobart. What seemed to help out the best was cleaning my Mill scale and contaminants down to clean Steel. Like others have mentioned try switching your tap settings up or down and see what your puddle and beads looks like, and get used to holding a real tight arc almost to the point of snuffing it out. One thing to check, is inside there is a capacitor on those old machines and if that capacitor is burnt out or fried the machine will not weld properly.

 

Figured I would post my settings.

 

Sorry about the sideways pictures no matter which way i take them they load that way. Ok. First High ground with 105 is my 1/8 Hobart AC7018 vert or 3/32 Washingto Alloy DC7018 flat. Second Low ground, 95 in WA 3/32 DC vert. Third is Hobart AC7018 1/8 flat. I had one stick of Mckay 111018 laying around, ran nice the same settings. Tried a Lincoln Excal, no dice. Last pic was a quick and dirty 3/32 vert. If it was ground it woulda looked better. But just wanted to throw it in there. Would i drag this around welding drill masts? No, i prefer my 1997 BigBlue 600D for those repairs, noisey 4cyl air cooled Dueutz and all. But I feel it would make a solid repair if i had too. Just my $0.02

 

Sorry about the sideways pictures no matter which way i take them they load that way./QUOTE]

Edit the pics on your phone before you upload. Meaning, rotate them.

 

In my hometown one of the local auto parts stores handled Forney welders. I think they were marketed as a “ Swiss Army” knife welder. Lots of gas stations had them because they had a battery charger timer circuit and connections for soldering irons. Just perfect for a gas station or farm.
My shop welder is a Lincoln Idealarc 250 which I run on DC reverse polarity 99% of the time. My favorite 7018 is Excalibur with Atom Arc ESAB a close second. I like the versatility of a DC machine as it allows you a wider range of all types of electrodes. Just my opinion

Sent from my iPhone using Tapatalk

 

Thanks for posting pics, better resolution than the one I found. Many of the old machine have the multiple taps . I think its that there are high and low grounds that confuse people

.


I think you explanation was pretty good . I wonder if it helped the OP at all.