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Cheap arc welder arrived
- Thread starter #12
- Start date
I have a 120 volt Century AC stick welder I picked up cheap on a scratch and dent sale a good 25 years ago that would probably be similar to what you have.
I don't use it much but I still do now and then. I can say that initially it was friggin useless but with a few minor tweaks it turned out to be a fair little stick machine!
First thing as you already have planed replace all the crappy undersized primary wiring with 10 ga and set it up with a 30 amp circuit to power it.
Second, replace the crappy undersized secondary wire (probably 8 - 10 ga) with 6 ga fine strand copper welding cable and try not to get much over 8 feet on each lead. The low arc voltage doesn't give you much headroom to play with regarding cable losses.
Third, add a fan or if it has a fan crank that sucker up with something bigger.
Fourth, add some sort of high temperature limit or warning systems. A simple bimetallic thermal switch (out of a old potted fluorescent light ballast for a cheap one) that sounds a alarm or kicks out the power when the transformer gets too hot is a must.
Fifth, get yourself some brand name 3/32" 6011 or 7014 rods. They burn smooth and easy at 50 - 100 amps.
After that you maybe surprised to find out that little buzz box will do a half decent weld on metal up to ~3/16" in a single pass and 3/8" in multiple passes!
I welded my neighbors steel frame shop back down to its base plates when high winds broke the crappy welds it was put down with off about 16 - 17 years ago with mine. I had to wire two 20 amp circuits together and feed it with on dual 12 ga cords to make the 50 foot reach to the three broken wall beam base plates but it did dang good weld that's ket that shop there ever since!
As for drying out your rods unless they have somehow gotten soaked I wouldn't worry about it. I rarely ever bake a welding rod and the few time I have ever had to I just tossed them in the kitchen oven on a cake pan and let them sit for a hour or so at 250 F.
The rest is just learning how to find the balance between frustration and impatience while making a puddle of molten metal do what you want.
I don't use it much but I still do now and then. I can say that initially it was friggin useless but with a few minor tweaks it turned out to be a fair little stick machine!
First thing as you already have planed replace all the crappy undersized primary wiring with 10 ga and set it up with a 30 amp circuit to power it.
Second, replace the crappy undersized secondary wire (probably 8 - 10 ga) with 6 ga fine strand copper welding cable and try not to get much over 8 feet on each lead. The low arc voltage doesn't give you much headroom to play with regarding cable losses.
Third, add a fan or if it has a fan crank that sucker up with something bigger.
Fourth, add some sort of high temperature limit or warning systems. A simple bimetallic thermal switch (out of a old potted fluorescent light ballast for a cheap one) that sounds a alarm or kicks out the power when the transformer gets too hot is a must.
Fifth, get yourself some brand name 3/32" 6011 or 7014 rods. They burn smooth and easy at 50 - 100 amps.
After that you maybe surprised to find out that little buzz box will do a half decent weld on metal up to ~3/16" in a single pass and 3/8" in multiple passes!
I welded my neighbors steel frame shop back down to its base plates when high winds broke the crappy welds it was put down with off about 16 - 17 years ago with mine. I had to wire two 20 amp circuits together and feed it with on dual 12 ga cords to make the 50 foot reach to the three broken wall beam base plates but it did dang good weld that's ket that shop there ever since!
As for drying out your rods unless they have somehow gotten soaked I wouldn't worry about it. I rarely ever bake a welding rod and the few time I have ever had to I just tossed them in the kitchen oven on a cake pan and let them sit for a hour or so at 250 F.
The rest is just learning how to find the balance between frustration and impatience while making a puddle of molten metal do what you want.
Lotsa good stuff there. Pizza just went in at 400F. When it gets done, I'll cook the welding rods because nobody knows how many years this has been sitting around unused. It came with 1/8th and 3/16th rods that have never been opened. They are labeled, "Chicago Electric", so that means they are crap...but I'll burn a few just so I'll appreciate good rods when I get them.
I see you saying they are a little too fat.
It already has a 90C Kilxon on the transformer. I was thinking about adding a fan to supplement the slots all over the case but I don't have any 240VAC fans laying around.
Easy enough to cure. It merely takes time...and tin snips.
I did think about the size of the output wires. Not generous!
When you DC, which polarity does the rod go on?
I see you saying they are a little too fat.
It already has a 90C Kilxon on the transformer. I was thinking about adding a fan to supplement the slots all over the case but I don't have any 240VAC fans laying around.
Easy enough to cure. It merely takes time...and tin snips.
I did think about the size of the output wires. Not generous!
When you DC, which polarity does the rod go on?
profbuxton
- Joined Feb 21, 2014
- 421
#12, I have a couple of 240V fan trays with six fans on each. How much is postage???
Gee... If there was only some way to know where profbuxton was located on this planet of ours.#12, I have a couple of 240V fan trays with six fans on each. How much is postage???
I would think that with properly sized wiring on the primary and secondary 8 10 ga primary 4 - 6 ga secondary you should be able to squeeze the 135 amp rating out of it without too much trouble which will run a 1/8" 6011 or 7014 AC rod pretty well and make for a decent weld in most situations.
The down side with those cheap welders is they tend to design them like most microwave oven power supplies and use high resistance aluminum windings to help cheat the fact that they are running their iron cores at close to full saturation in typical operation hence the high input current draw despite the moderately low output voltage and current for it which means you will probably see a ~ 5 - 6+KVA input for ~ 2.5 - 3 KW output.
The down side with those cheap welders is they tend to design them like most microwave oven power supplies and use high resistance aluminum windings to help cheat the fact that they are running their iron cores at close to full saturation in typical operation hence the high input current draw despite the moderately low output voltage and current for it which means you will probably see a ~ 5 - 6+KVA input for ~ 2.5 - 3 KW output.
At 10% duty cycle, that's only 7.8 cents per hour.you will probably see a ~ 5 - 6+KVA input for ~ 2.5 - 3 KW output.
It's going to take me a long time to use up enough electricity to make a free welder unprofitable.
Operating cost isn't the issue. It's the knowing how much power you're putting in for what little you get out that's the kicker.
The buddy of mine with big scrap yard has an old Miller 200 wire feed rig sitting on the side of his scrap yard the last time I was there a few weeks ago. It's a bit dinged up but looked like it may still well within my fixing range. I would have grabbed it but it was too frozen down to move. Next time I am there I will give it a closer look and if it's not burned out beyond repair is coming home with me!
The buddy of mine with big scrap yard has an old Miller 200 wire feed rig sitting on the side of his scrap yard the last time I was there a few weeks ago. It's a bit dinged up but looked like it may still well within my fixing range. I would have grabbed it but it was too frozen down to move. Next time I am there I will give it a closer look and if it's not burned out beyond repair is coming home with me!
So it's low efficiency. Another form of low efficiency is having a welder and not being able to use it because I don't know how.Operating cost isn't the issue. It's the knowing how much power you're putting in for what little you get out that's the kicker.
I'm willing to pay 8 cents per hour for education, even if the only education I get is that I suck at welding.
Check your helmet. I have a "solar powered" version that I thought was really solar powered. It suddenly stopped operating correctly (nothing beats looking at a welding flash WITHOUT proper eye protection). It turns out that there are two 3 V lithium button cells inside on the PCB. They are NOT user replaceable (but you CAN remove / replace them - requires various degrees of teardown).
If you have to, get a $39 HF auto-dark helmet (and apply their 20% off coupon). They do work well (and DO have the batteries), but having an auto darkening helmet is a game changer. I learned using the old "flip down" helmet, meaning that you could not see your work until you struck an arc. It is nice being able to see your work prior to arc-strike.
If you have to, get a $39 HF auto-dark helmet (and apply their 20% off coupon). They do work well (and DO have the batteries), but having an auto darkening helmet is a game changer. I learned using the old "flip down" helmet, meaning that you could not see your work until you struck an arc. It is nice being able to see your work prior to arc-strike.
The First Minute didn't work.
I got the old welding helmet out and gave it a major douche. It must have worked at one time because you would have to use it for at least a year to get that much rancid sweat in the headband.
Look Ma, no batteries!
It's solar powered. I can look into the sun and dial the whole sky down to a round dot in the center.
So I cleaned everything, adjusted everything, and set the welder for 40 amps DC with a 1/8th inch stick.
No response from the helmet. It's set on high sensitivity, quick response, and dialed down to, "stare into the sun" worth of darkness but it doesn't respond to a welding event.
I guess that's why I got it for free.
I could guess that I should have done something different to get the helmet to respond, like not being in the shed with 640 watts of fluorescent light (16 four foot tubes) in 140 square feet or using a lot higher power for the arc, but I'm not going to go blind trying to figure out why it won't respond.
Hmmm...maybe the goggles that came with my oxy-acetylene kit...
I got the old welding helmet out and gave it a major douche. It must have worked at one time because you would have to use it for at least a year to get that much rancid sweat in the headband.
Look Ma, no batteries!
It's solar powered. I can look into the sun and dial the whole sky down to a round dot in the center.
So I cleaned everything, adjusted everything, and set the welder for 40 amps DC with a 1/8th inch stick.
No response from the helmet. It's set on high sensitivity, quick response, and dialed down to, "stare into the sun" worth of darkness but it doesn't respond to a welding event.
I guess that's why I got it for free.
I could guess that I should have done something different to get the helmet to respond, like not being in the shed with 640 watts of fluorescent light (16 four foot tubes) in 140 square feet or using a lot higher power for the arc, but I'm not going to go blind trying to figure out why it won't respond.
Hmmm...maybe the goggles that came with my oxy-acetylene kit...
Assuming the helmet has shading adjustments anything over 8 is sufficient for sub 100 amp welding. Most of my helmets are set for ~ 9 - 10 at the most even for doing 200+ amp stick work.
As for not responding the photosensors may need cleaning or possibly at 40 amps the spark was not bright enough to even register as being bright enough to need to react to. If it's responding to normal sunlight it's probably sensing and working correctly.
Also with a 1/8" rod and no applicable welding experience you will never strike and hold an arc at 40 amps to begin with. At that current even keeping one going with a good 3/32" rod is hard.
For beginner work and getting the feel I would start at ~ 100 amps with that size of rod and once you get the feel for keeping an arc going while running a decent bead start working your way back to around 70 - 80.
As for not responding the photosensors may need cleaning or possibly at 40 amps the spark was not bright enough to even register as being bright enough to need to react to. If it's responding to normal sunlight it's probably sensing and working correctly.
Also with a 1/8" rod and no applicable welding experience you will never strike and hold an arc at 40 amps to begin with. At that current even keeping one going with a good 3/32" rod is hard.
For beginner work and getting the feel I would start at ~ 100 amps with that size of rod and once you get the feel for keeping an arc going while running a decent bead start working your way back to around 70 - 80.
I just tried 80 amps of AC and all I did was vaporize 6 inches of 1/8th rod and leave a few spatters of metal on top of the 1/2" steel plate...but thanks. You are the first person to recommend any settings for beginners. I'm surprised at how fast the welding rod disappears. I have a hunch that I could make a whole inch of weld with a 1/8th rod. Whadda ya think? What should I expect for a length of bead from one rod? I also have some 3/16th rods. I think I should go to a welding shop and watch for a while because I have no idea what to expect...how long to dwell on a single spot, what to expect out of a welding rod, whether it's easier to try to make a puddle in a corner or what a simple line is supposed to look like when it's finished. Maybe Youtube is the place to go.
ps, my eyes are rather sensitive to light. I almost can't drive a car in the Florida sun without sunglasses. The helmet says something like "8 to 14" for darkness. Seems like plenty of range.
That helps instantly!!!
About 8 seconds per inch to lay down a positive bead (lump) with 1/8th rod at 115 amps of DC, negative on the rod.
There must be a lot of learning how to move your hand. Kind of like writing from the far end of a 12 inch pencil.
I still didn't see how many inches of rod it takes to make an inch of "bead".
I'm off to burn some welding rods!
About 8 seconds per inch to lay down a positive bead (lump) with 1/8th rod at 115 amps of DC, negative on the rod.
There must be a lot of learning how to move your hand. Kind of like writing from the far end of a 12 inch pencil.
I still didn't see how many inches of rod it takes to make an inch of "bead".
I'm off to burn some welding rods!
There is no correct bead dimension to rod usage. You're just changing the metal from one shape to fill a volume of another and depending on what you are doing you may be laying a bed downto fill a huge gap which would use a lot of rod for very little distance or doing surface build up which may mean covering a wide path very thin and everything inbetween.
Same with what amperage to use. Depend non what you are doing it will vary. If you are doing fine work turn it down and move slow or if you need to do large heavy stuff turn it up and burn that weld puddle in fast and deep.
As for DC welding I almost always run DC postive with the rod postive and the work negative. It tends to put more heat into the workpiece faster than your rod giving you better control of things.
That said for begining work straight bead laying runs should lay a bead about 2 - 3 times the rod core width by roughy it's thickness in height.
The basic welding practice is to do swirls or zigzags as you move the rod down and in the direction you need to lay the bead. Also pay attention to where your weld puddle not the flux puddle is going. The flux puddle dimensions or actions have no relevance to the weld.
Personally for me when I took my welding classes in college just for stick welding I burned rods for ~ 3 hours a day 5 days a week for over a month at a rate of several large handfuls of rods per day. So given that even if you're a fast learner expect to burn up at least a 50# box of rods for every technique you learn to do with any proficiency.
Same with what amperage to use. Depend non what you are doing it will vary. If you are doing fine work turn it down and move slow or if you need to do large heavy stuff turn it up and burn that weld puddle in fast and deep.
As for DC welding I almost always run DC postive with the rod postive and the work negative. It tends to put more heat into the workpiece faster than your rod giving you better control of things.
That said for begining work straight bead laying runs should lay a bead about 2 - 3 times the rod core width by roughy it's thickness in height.
The basic welding practice is to do swirls or zigzags as you move the rod down and in the direction you need to lay the bead. Also pay attention to where your weld puddle not the flux puddle is going. The flux puddle dimensions or actions have no relevance to the weld.
Personally for me when I took my welding classes in college just for stick welding I burned rods for ~ 3 hours a day 5 days a week for over a month at a rate of several large handfuls of rods per day. So given that even if you're a fast learner expect to burn up at least a 50# box of rods for every technique you learn to do with any proficiency.
profbuxton
- Joined Feb 21, 2014
- 421
re welding helmets, Some time ago driving through an Indonesian village I noted a young guy in a metal shop welding a gate frame using sunglasses as eye protection. It looked like a " dab at it then look away approach". He's probably blind by now!
The batteries have no access door to replace them. You would have to disassemble the whole module to access the batteries.
Don't even think of trying to weld without a proper helmet. Also, cover all of your skin with natural fabric (cotton, leather) clothing. An arc burn (a sunburn caused by an electric arc) is 10X as bad as the worst sunburn of your life. It is like sunbathing on Mercury.
