Thoughts on this used welder?

[joshuabardwell]

Well, my neighbor came over and we installed the receptacle today, and I finally got to weld a little bit. Here are the results.





One piece of equipment that I'm lacking is a stiff wire brush, so the slag is not as cleaned off as it could be. Striking the arc was harder than I expected. I kept either pulling away too far or sticking the rod. The non-auto-darkening helmet couldn't be helping with that. I learned another advantage of an auto-darkening helment: if you accidentally touch the work piece and strike an arc before you drop the hood, you will get an eyefull. Oops. It was just the briefest of flashes, as I slammed my eyes shut and pulled the rod away, but woo hoo. I kept seeing that flash for 30 seconds or so. When I went back to weld again, I couldn't figure out why I wasn't seeing the arc. It was because I still had my eyes closed!

The only other time I have had an afterimage like that was when some good ol' boys I know showed me how to use a garbage bag and some oxyacetylene gas to make a bomb. That one lasted way longer than 30 seconds.

EDIT TO ADD: I also wear eyeglasses, which have UV-protective lenses, so that should help to protect against the flash damage. But how much flash does it take to give you flash burn in your eyes? Would a brief one like I experienced do it?

EDIT TO ALSO ADD: Okay, I have wire brushes around the house, yes, but not one of those big stiff ones they use for cleaning welds. Didn't want y'all to get the wrong impression about my tool-cred.

 

[k0ua]

Couple of things Joshua.. On the wire brush, I find putting a wire wheel on you 4 or 4 1/2 inch angle grinder is way better than a wire brush. A heck of a lot less work and better results.. On the rusty metal, clean it first with that wire wheel and the arc will be easier to start and the results will look better.. sure 6011 will cut thru rust and dirt somewhat, but all rods will do a better job on clean metal. As soon as the funds allow get an autodarkening helmet.. Your welding will improve and your general state of mind will improve. I am sure the flash, (we have all done it) was no fun, But it will happen a lot less with the auto dark helmet. You will not be so worried about forgetting and flashing again..You don't want to develop a welding flinch The vertical bead did not look to bad to me. Just a few more pounds of rods and you will be ready to start making things. Maybe sooner.. stay with it. It is worthwhile.

James K0UA

 

[Shield Arc]

how much flash does it take to give you flash burn in your eyes?

One sure way to tell! Tomorrow morning around 1, 2, 3:00 A.M. If you set up in bed, and it feels like someone poured hot sand in your eyes, guess what?

 

[joshuabardwell]

Thanks for the words of encouragement, James. For the record, the "vertical" bead was actually in flat position. I just turned it that way to take the picture. For cleaning the slag, yes, I have heard a wire wheel is the way to go. Do you like the "regular" crimped-wire kind or is the "coiled-wire" kind better? Do you know what I mean? I cleaned a patch of that metal for my practice welds with a grinding wheel, but you wouldn't know it after I got done working on it. I really need to get a wire wheel to clean the slag off, so I can see what I'm doing.

The rods I was using are E6011. The box said between 80 and 120 amps, so I went dead to the middle of the range at about 100 amps. Maybe 90, because if I recall correctly, that's where that welder maxes out at 100% duty cycle. Anyway, after burning a few of them, I gave DC- a try, but I just could not get the arc started. At first I realized that I was reading the AC scale on the lever and had the power way too low, but even at around 100-110 amps DC, it would just fizzle out. It was surprising, because DC is supposed to be easier to weld with, right? So I hear.

It's funny to me that the welder goes straight from 100% duty cycle right to 20%. Seems like the scale would be more graded than that. I do see one advantage of AC that I hadn't previously considered, and that's that you can get a higher amperage at 100% duty cycle. So if you don't want to take breaks every two minutes, and can get by with AC, it seems like you might choose it even though DC is more stable.

 

[joshuabardwell]

One sure way to tell! Tomorrow morning around 1, 2, 3:00 A.M. If you set up in bed, and it feels like someone poured hot sand in your eyes, guess what?

Ha ha. So it could just be a tiny flash like that?

Oh great. Now my eyes are itching just because I'm thinking about it.

 

[k0ua]

Thanks for the words of encouragement, James. For the record, the "vertical" bead was actually in flat position. I just turned it that way to take the picture. For cleaning the slag, yes, I have heard a wire wheel is the way to go. Do you like the "regular" crimped-wire kind or is the "coiled-wire" kind better? Do you know what I mean? I cleaned a patch of that metal for my practice welds with a grinding wheel, but you wouldn't know it after I got done working on it. I really need to get a wire wheel to clean the slag off, so I can see what I'm doing.

The rods I was using are E6011. The box said between 80 and 120 amps, so I went dead to the middle of the range at about 100 amps. Maybe 90, because if I recall correctly, that's where that welder maxes out at 100% duty cycle. Anyway, after burning a few of them, I gave DC- a try, but I just could not get the arc started. At first I realized that I was reading the AC scale on the lever and had the power way too low, but even at around 100-110 amps DC, it would just fizzle out. It was surprising, because DC is supposed to be easier to weld with, right? So I hear.

It's funny to me that the welder goes straight from 100% duty cycle right to 20%. Seems like the scale would be more graded than that. I do see one advantage of AC that I hadn't previously considered, and that's that you can get a higher amperage at 100% duty cycle. So if you don't want to take breaks every two minutes, and can get by with AC, it seems like you might choose it even though DC is more stable.

DC is usually quite a bit smoother than AC, less "buckshot" bb's and usually a better looking weld bead. Offers larger choice of rods. It is more quiet also. You might get a little 7014 3/32 rod, about 100 to maybe 110 amps. DC Electrode Positive. they make a smooth bead without a whole lot of ripple in it. But they are pretty easy to run, you can kinda just drag them on the work, You do have to move a little faster than some rods, as the depositon rate is higher. The are considered an "idiot proof rod" Not trying to say anything here, but that they are just easier to run. 7018 runs really well, but can be a little daunting to strike and restrike sometimes. You should really try the 7014 on DC,, I think you will like them. I don't know about where you live, but here we can find the US Forge small packages of rounds like 1 lb packages so you do not have to spend much over $3 to try a rod out...It is true you will get more amps out of your welder on AC, but I think you will find DC to be the better mode for most things once you get going.

James K0UA

 

[joshuabardwell]

Well, it looks like the fan is still having an issue after all. It's not a question of lubrication, unfortunately. When the welder is off, the fan spins freely. When it is powered on, it actually is encountering resistance. It will spin for maybe a quarter or half-turn and then bind up. If I move it past the binding point with my hand, it spins another quarter or half-turn and then binds again. I disassembled the motor and cleaned it out, after which it will spin for about fifteen seconds, slowing down the whole time, until it binds up again--almost as if the motor is heating up and that is causing it to bog down.

Any thoughts?

 

[joshuabardwell]

Here's a video.

 

[undercut]

Is changing out the fan an option for you? Those fans are typically pretty smooth and easy running. For it to start pretty strong and then sputter out like that, might not be worth your while to try to fix it or worse, be welding and have it fail and let your welder get crispy. If replacing isn't an option, are you sure there isn't any binding when you spin the fan with your fingers with the power off. There should be absolutely no friction.

 

[joshuabardwell]

I'm going to change out the fan, yes. I started another thread dedicated to the issue, and a suitable--and suitably cheap!--replacement was suggested.

The malfunction is quite odd. The fan turns absolutely smoothly when the welder is off, so it doesn't seem like a bearing issue. It's only when the motor is on that it binds like that.

 

[cqaigy2]

I'm going to change out the fan, yes. I started another thread dedicated to the issue, and a suitable--and suitably cheap!--replacement was suggested.

The malfunction is quite odd. The fan turns absolutely smoothly when the welder is off, so it doesn't seem like a bearing issue. It's only when the motor is on that it binds like that.

Sometimes they will shift forward or backward and bind.

 

[joshuabardwell]

Well, the fan is still not fixed, but I took the cover off the welder and aimed a box fan at it so I could get a little more practice in. I moved from the relatively shaded part of my driveway that I was working on to an in-the-sun part, and lo and behold, I could actually SEE the rod and the work piece, just a tiny bit. Made starting the arc much easier, although I still have a lot of practice to go. At least I wasn't going by feel alone, though, just stab-stab-stabbing at the piece until I got lucky. Here are some of my practice beads.



These are all AC E6011. One question that I have is what is the "crackly" black material at the edges of the bead? Is it just flux that is not getting brushed off? Or is that undercutting? Or something else?

I tried again to use DC, but no love. The rod would stick immediately no matter what I did. I even tried turning the amps all the way up on the machine. I could see that the rod was a lot hotter: the sparks it made while scratching were larger and the flares it made when I pulled it away after sticking were larger, but no arc. Finally, with the most careful of careful motions, I was able to strike a very precarious arc (at recommended amperage for the rod). The pool moved very slowly and the hot metal wanted to actually bead up and roll along the surface of the work piece. When I was done, there was very little penetration and lots of tall build-up of weld metal, some of which cracked off when I brushed off the slag. See below for two examples:



I can't for the life of me figure out what's going on here. Maybe I should spring for a box of fresh rods just to rule that out. Or is this just lack of technique? DC is supposed to be easier, but so far, I cannot even really get started with it. For the very-brief time that I actually had a DC arc going, I thought I got a sense of its benefits. The pool was steady and not spattering and jumping around. I want more of that!

BTW, I also tried both AC and DC with E7018, but with terrible results. But since those are low-hydrogen and they have not been stored in a dry location, I would chalk that up to the rods.

 

[ChristianHF]

From a web site I frequent Welding Tips and Tricks - TIG, MIG, Stick and a pantload of other info

I'm just starting stick welding, and have recently tried to "graduate" from E6013 to E6011 Welding Rods, as you suggest. Problem is, when I finish a weld using E6011 rods, I always wind up with a fairly large crater at the end of the weld seam, because the E6011 is so "aggressive". How do I avoid this?
Answer to E6011 welding rods Question

I know exactly what you are talking about.

2 welding tips come to mind for getting rid of the crater problem at the end of the weld:

1. Make sure your amperage is not too hot and if you are welding on an AC DC machine, AC works better. DC will allow Arc Blow to start happening midway into burning the rod. E6011 rods are made to run on all polarities but AC seems to be the sweet spot and will definitely prevent arc blow (when a magnetic field sets up and causes the rod to burn unevenly and be extra aggressive).

2. When you stop the bead, keep the rod in the area and light right back up in the crater with a close arc for about a second after the crater has had a few seconds to cool. that should fill the crater without making a new one.

The reason I like E6011 rods better than 6013 rods is that I have seen lots of students have trouble with the 6013 rods trapping slag pockets. 6013 rods make a pretty weld under pristine conditions, but when you have to burn thru a little rust, or weld downhill, they just plain suck. E6011 rods come in 5/32" diameter also and even if all you have is a 200 amp buzz box and E6011 rods, you can weld a lot of stuff.

 

[cowski]

can you post a picture with the leads plugged in {dc}.oil the fan bearings.get some 1/8 6011 rods.burn them about 100 then burn some at 120.maybe we can figure out why dc is not working.

 

[joshuabardwell]

can you post a picture with the leads plugged in {dc}.oil the fan bearings.get some 1/8 6011 rods.burn them about 100 then burn some at 120.maybe we can figure out why dc is not working.

Here's a photo of the leads plugged into the DC terminals.



I am looking into whether I may have a bad rectifier. As a start, I put a multimeter on the DC terminals. I measured 55 VDC, which if I understand correctly is about the right range. On a hunch, I set the multimeter to AC and measured 22 VAC. I don't know a lot about rectifiers, but should any AC at all be coming out of there?

 

[joshuabardwell]

I did a little more testing with a multimeter. The rectifier bridge has four diodes as near as I can tell. Two of them show 3.3 MOhms through them and 0.44 volts drop using the multimeter's diode test function. The other two show 2.5 MOhms and 0.41 volts drop. Not knowing the specific model of the rectifier (I will have to get a mirror to read it, I think) I don't know for sure whether this is within spec, but it passes the most basic diode test: you have a voltage drop one way and an open the other. (I verified the opens too.)

EDIT TO ADD: Of course, with mega-ohms of resistance one way, perhaps it makes more sense to conclude that the diodes are open both ways.

 

[dex3361]

Here's a photo of the leads plugged into the DC terminals.

View attachment 281818

I am looking into whether I may have a bad rectifier. As a start, I put a multimeter on the DC terminals. I measured 55 VDC, which if I understand correctly is about the right range. On a hunch, I set the multimeter to AC and measured 22 VAC. I don't know a lot about rectifiers, but should any AC at all be coming out of there?

Best way to tell is test the diodes and see if they are good. Not real hard to do once you locate the diodes. There should be 4 of them. They may look like this DIODE. Here is a description of how to test the diodes. DIODE TESTING.

 

[k0ua]

Joshua, I am sure sorry you are having so much trouble with the welder. Yes DC is much nicer to weld with than AC, and I am having trouble understanding why yours does not seem to work..Maybe Shield Arc could help if he comes across this.. Those DC "welds" are called "bird turds" I have heard of this with MIG welders but never seen this on an arc machine. I am wondering if the diodes are bad in some way that cannot deliver much current or there is a high resistance joint somewhere. I am just not sure what the problem is, Obviously your transformer seems good as it will weld on AC but sure does not seem to do much on DC. I sure hope you get it going and start enjoying DC welding.

James K0UA

 

[cowski]

your dc welds are cold.weld a few passes with the dc turned all the way up.then swap the cables and try a few more.post them and let me look . also clean your welding plugs.i use a car battery brush.check your 220 receptacle and make sure it has enough voltage.

 

[joshuabardwell]

Here is a description of how to test the diodes. DIODE TESTING.

According to your test, the diodes should have a resistance of between 0 and 1 ohm. Mine have a resistance between 2.5 and 3.3 mega-ohms. That certainly would seem to cause cold welds. However, I have not disconnected them from the heat sink (would require desoldering) and I read that that may cause incorrect readings.

EDIT TO ADD: A thread on the Miller forum indicates that diode resistance over about 1 mega-ohm should be treated as "open" and indicative of a bad diode. Sounds like I have four bad diodes and the next step is to replace them. Good thing I know how to solder! Now to figure out what the correct part number(s) are. Urgh.

I know that heat is one of the main things that causes diodes to fail. What do you want to bet a previous owner operated the welder with the broken fan and toasted the diodes? Oh well. I said when I bought it that $100 was a fine price for an AC-only welder in this range. Looks like that's what I ended up paying for. It even came with a nifty hand truck included!