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For most work, it is my understanding that D/C stick is the way to go. What is the reason, and when/what situation is A/C stick a better choice? I know that 7018 AC rods can be utilized on both A/C and D/C welds, but what determines which process? Inquiring minds want to know!Miller Multimatic 215Spoolmatic 150 spool gunPrimeweld Cut 60 Plasma CutterVevor Pipe StandsBauer Portaband/Swag tableGrinders-Milwaukee, Porter Cable, DewaltArcUnion M-20 portable rod oven
Reply:AC rods eliminate arc blow. That's about it. Can't see any other benefits.
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Reply:
Originally Posted by Oscar
AC rods eliminate arc blow. That's about it. Can't see any other benefits.
Reply:The biggest reason today is cost.Upto 1970's DC was very costly. Even today AC is cheaper not as bad.There other reasons are out weight by being a very smooth welded. Dave
Originally Posted by RCWelds
For most work, it is my understanding that D/C stick is the way to go. What is the reason, and when/what situation is A/C stick a better choice? I know that 7018 AC rods can be utilized on both A/C and D/C welds, but what determines which process? Inquiring minds want to know!
Reply:I agreed 👍 Dave
Originally Posted by Oscar
AC rods eliminate arc blow. That's about it. Can't see any other benefits.
Reply:
Originally Posted by RCWelds
Am I correct that some arc blow can be eliminated by moving the ground clamp farther away from the actual weld?
Reply:
Originally Posted by RCWelds
Am I correct that some arc blow can be eliminated by moving the ground clamp farther away from the actual weld?
Reply:Arc blow gets a lot of press, but in the year I've had my DC welder I have yet to see it. Just switch back to AC for that weld if I do. Like Dave says, the DC is a smoother weld and it "should" work better for out of position welds. Every machine will be a little different though. I pretty much use DCEP for almost everything now. If I'm going back to the AC buzz boxes it's usually for better portability (moving the welder outside)...The harder you fall, the higher you bounce...250 amp Miller DialArc AC/DC StickF-225 amp Forney AC Stick230 amp Sears AC StickLincoln 180C MIGVictor Medalist 350 O/ACut 50 PlasmaLes
Reply:I tack both ends before welding the part. Dave
Originally Posted by whtbaron
Arc blow gets a lot of press, but in the year I've had my DC welder I have yet to see it. Just switch back to AC for that weld if I do. Like Dave says, the DC is a smoother weld and it "should" work better for out of position welds. Every machine will be a little different though. I pretty much use DCEP for almost everything now. If I'm going back to the AC buzz boxes it's usually for better portability (moving the welder outside)...
Reply:
Originally Posted by RCWelds
For most work, it is my understanding that D/C stick is the way to go. What is the reason, and when/what situation is A/C stick a better choice? I know that 7018 AC rods can be utilized on both A/C and D/C welds, but what determines which process? Inquiring minds want to know!
Reply:
Originally Posted by RCWelds
For most work, it is my understanding that D/C stick is the way to go. What is the reason, and when/what situation is A/C stick a better choice? I know that 7018 AC rods can be utilized on both A/C and D/C welds, but what determines which process? Inquiring minds want to know!
Reply:I have seen arc blow. Most of the time it is subtle and a pain in the a$$, but I have seen it very strong where I had to stop the weld.As far as the ground clamp, you want to weld away from it, so the arc will remain in the puddle. If you are welding towards the ground clamp, you might see the arc try to go forward instead of dragging behind your electrode. But that is a good way to actually see it."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!
" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:I have seen arc blow. Most of the time it is subtle and a pain in the a$$, but I have seen it very strong where I had to stop the weld.As far as the ground clamp, you want to weld away from it, so the arc will remain in the puddle. If you are welding towards the ground clamp, you might see the arc try to go forward instead of dragging behind your electrode. But that is a good way to actually see it."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!
" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:Since all welds I do I tack both ends. With Stick and fluxcore I took some time to remember a book had welding saying to tack both ends and had drawing of a U magnet 🧲 show how arc would try to weld to one side. So to stop that tack both ends before welding. Note 📝 I read book in the 1960's Dave
Originally Posted by WNY_TomB
I have seen arc blow welding structural steel hundreds if not thousands of times (if you weld over 1000 tons of steel you are bound to see it), depends on part shape and if over 150 and especially 200 amps. you weld 3/8" or thicker and if you want to weld reasonably fast you use 5/32, 3/16 or bigger usually 7018. 5/32 7018 usually 150 to 200 amps or more, mild arc blow you can lean the rod to compensate but over 200 amps its easier to use AC rod.basically you can weld 4" per minute using low amps (small rod) or go at least 10" per minute (often over 20 ipm) using bigger rod. Welding Procedure Handbook often says use hugh rod like 7/32 rod at 300 amps for relatively thin 1/2" plate. but I myself have never used bigger than 3/16" rod cause normally I was welding 1/2" thick or thinner. obviously if all you weld is over 3/4" thickyou would use a bigger rod than 3/16" normally and AC
Reply:I almost never see it. But,,, does this sound like a guy gonna turner up tomorrow and grab a fist full of 1/4 and go to work at 300A continuous? Last time I used really big rod was full pen col splices adding couple more stories on top of 7, 2 inch stuff on top of a hospital. Rosebuds, preheat, DC,,, 200SA wide open 7/32. In the winter, it really make them grunt and if they were not in tune wouldnt run them. This guy is a poster child for a DC buzzer, set it to DC reverse and bust the knobs off so he aint tempted to fool with them. Got mine in 83, switch been moved once or twice and once was for a net pic for AC rod. Operator has to work like a sled dog to keep it from runnjn.
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Last edited by Sberry; 5 Days Ago at 05:51 PM.www.urkafarms.com
Reply:I saw a fairly decent amount of arc blow using 1/8" and 5/32" 7018 at the community college where I took a course...and this was according to the instructor, not me. (I didn't know why I was having trouble at first..) Was generally able to make it go away by moving the ground clamp and/or adding some metal "downstream" of where the arc blow was occurring...those machines didn't have AC current available...
Reply:Reason I even harp on some of these things is because it distracts from really importyant things when picking a right machine for them. There is a reason you cont see AC/DC on the new stick inverters,,, main one being cause its not needed. Only timne polarity was even changed was when using tig and fluxcore. With old timey type rods some used to change for 6012 and 13 on occasion for sheet but only time I ever even see a test with anything other than 10 and 18 is 11 on sheet for a sheet company and that was 3/32 dcrp. Galv sheet, real light stuff. I am not sure what the drywall stud guys use. Now,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, ,,,,,,,,,,,,,,, thats not saying others dont,,,, that they havnt, that it doesnt exist but its pretty rare to the point that in a varied career never seen it and really the only time "out there" I see anything else like 6013 is part timers (not saying they aint good) and where weld is somewhat secondary,,,, not in the welding biz but equipment dealers with bunch old farts in old shops using 6013 on signs,,, bout the only real "trade" time I ever see it used. I am sure some place somewhere but I am cautious with the words ever and never. Some specialist use other stuff some 24 and higher tensile but they aint the guy asking how to reverse polarity on an AC welder,,,Last edited by Sberry; 4 Days Ago at 08:59 AM.www.urkafarms.com
Reply:This is why I am a fan of the new welders, they didnt need to waste to get to where we want to be,,,, DC with enough power to melt it off and for mosty real practical purpose here the rest is just fog. You dont see people selling DC machines to get AC??? Not for common sticks. 49 yrs of this and never went to an Ironwork or fitter job and used an AC machine,,,, NEVER. Not saying a couple didnt have it on it but never. I know flange jocky welds low pressure pipe with 13 but again,,, not here, not saying you cant but I bout place money you go to a real project wont see it in a test booth, I never have.Last edited by Sberry; 4 Days Ago at 09:01 AM.www.urkafarms.com
Reply:What is the reason, and when/what situation is A/C stick a better choice?
Reply:
Originally Posted by Sberry
DC machines to get AC??? Not for common sticks. 49 yrs of this and never went to an Ironwork or fitter job and used an AC machine,,,, NEVER.
Reply:There are old timers here recommend some old lame unit as a project but I think they are really out of touch,,,, after asll, get an old machine so you can get an expensiv e repair part for it years down the line,,,, way cheaper especially with some of the warranties,,, replace it with one with newer features and even moree effecient in a couple 3 years and only reason they havnt lasted by the numbers for decades is,,, they only been here for 5 years and some even less. Yes old cheap crap failed, duh so did plenty of new hi dollar suckers and can now have a working machine in hand off the shelf for the cost of a board to a machine a guy paid 5K for 5 years ago. Evern look at this forum, 95% of the trouble shooting here done to expensive equipment. Got an expert career welder now uses a 169 dollar unit for everything he can find to toss at it. He realizes what he needs to do it, doesnt want to be without a welder he has had all his life but realistic about the nature and amount of work and,,, it works. Go to common household trash day,,, look and see lots of items tossed in this price range, be different if it cost 3000 dollars but for 300 to do it aint worth it all to Joe hometime and not worth it to do without if you need it. These entry welders are fantastic at this price,,, yes,,,,,,,,,,,,,,,,,,,, they are disposable but that is actually an asset, dont got to try to sell it, not much anguish here and even fast food worker could scrape it together for this. I wish they had these when I was slumming, would have added it to the kit. Up till the recent time doing anything out of reach and moving heavy equipment was the only way, almost all my utility out of shop was engine drive, now anything on site and 100 ft from an outlet can do it. Yes,,,,,,,,,,,,,,,,,,, for Capt Obvious, cant weld continuous battle ship but good share of a nuke built with little dinky rods. Dont need to do heavy fab in every corner, dont need 100A service everywhere except where its needed. That is often a hard concept to grasp, often takes a long time to develop a real sense of demand and some have a hard time with the difference between a little and a lot. Its often hard to fathom that its not always good to have as big as possible. Now days with low flow simply run a 3/8 pex on the hot to bathroom faucet vs the old,,,, I got 3/4 to everything so I donnt lose a pound of pressure thinking.www.urkafarms.com
Reply:Like some said, the blow thing becomes part of the purchase decision if its not addressed in good context. Every time a guy shoves a rod in an acute angle its now become blow. It come I think with the explosion of the mitered tube angle which was rarely used in job shops of old. I also mention I can pretty well get by without a saw does 45. Its all right, nothing morally wrong with it just wouldnt be real hi to start out with. I am not talking to Ls or Oscar or others that really do need, I get that but as a general fabricator,,, as Dave says, most of it in a 5 gallon bucket and 2 for big jobs. After a while if a guy is doing it right doesnt need a lot more. I dont even want it anymore, cant make any more by getting more or upgrade, would be first in line if it did. Got a lot of dead weight I could part with, problem its old and worn and not pristine but even then rathger generic, as a collection semi priceless, as a cash value only minor. I saw another forum,,, guy squeezed and bought a 4K snapper welder on credit and now gonna save some more months for some number 6 wire for this 30A machine cause he has read its good to not lose a volt for his long 43 ft circuit. Makes me wonder what kind of council he got about this, a number 12 cable and a 300$ welder with an 80 bottle was for him and he could have used the thing he bought, prolly still isnt hooked up.Last edited by Sberry; 4 Days Ago at 10:17 AM.www.urkafarms.com
Reply:Only reason to AC weld today is if its all you got. I know guys build just fine with them. If a guy can only afford a machine cost 60 or 75 used I spose he could do that but considering some of the other cost and even assosiated cost with and cord and cable makes a 200$ DVI stick look like a bargain. Maxstars were not a cheap machine but no AC and while it would tig it is a good stick machine. I am a convert. I am not likely to upgrade but if I was starting over aint no way and no how I wouldnt try to enter some of this as painlless as practical. Used to be gut wrenching money at every turn, can still spend a lot but I would get my feet wet with some decent practical pieces and go from there. If a guy comes up with interest in Aero space face it when it happens.Last edited by Sberry; 4 Days Ago at 10:40 AM.www.urkafarms.com
Reply:
Originally Posted by Oscar
I've read that moving the work clamp closer to the end of the weld helps mitigate arc blow, not further away from the weld joint. Can't say it's been an issue for me though.
Reply:Arc blow is not a big problem in my experience. I bought my first welder (AC) in 1974. DC was $100. more. I hated myself for not getting DC. There was no internet then, & my friend took a course in night school, came home with a 1/4" steel bird house, I'd have buried to prevent anyone from seeing it.It was an era where instruction from skilled weldors was hard to find. Every farmer had a "buzz box" NONE of them knew how to use them. I bought several books, but they weren't much help to me. I never mastered vertical up with AC. To this day, I can't say whether I should blame my lack of skill, or the welder.A few years later, I bought a DC sibling to my first welder. Suddenly, I could weld vertical!I'm no expert stick welder, but all the builds from my younger days were AC. I'd choose it if you can turn your work to always be flat. I have pictures if I could find them of a 20 year old kid using an A frame crane on the front of a 1936 Dodge 1-1/2 ton truck to hoist a car hauler trailer to position all welds horizontal. It was far more work, but the trailer is still in use 46 years later.All that said, I still don't know if vertical welds can be produced with AC, I had no success. If buying a welder I would NOT consider AC only.An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.All that said, I still don't know if vertical welds can be produced with AC, I had no success. If buying a welder I would NOT consider AC only. |
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发表于 2022-8-7 15:51:39