I have a old generic MIG welder with the 'A-B 1-2 Hi-low' adjustments. I was welding thin panel steel with 0.8 fluxcore wire and found even the lowest setting, one speed setting of less than 1. Was still a bit too hot and the wire a bit too fast.
I have used an different one once and it seemed to weld nicer smaller welds than mine. I could do the job I wanted to at the time. But would like to do tiny thin, almost TIG welds with almost no filler metal in the weld. Can I just make another tapping off the transformer? I think I could do something about the motors wire speed. But I do really need even lower amps than what it can put put. But I am not sure how to tap the transformer so it puts out lower amps and how changing the Volts and watts affects it.
I hope to make small models of things from scrap steel, its tube and thin bolts and sheet etc, so I need tiny welds without much filler metal buildup. Thanks.
daryl14,
Jan 3, 4:36am
I'm not a professional welder but something tells me you will end up steering towards a new inverter welder with perhaps a mig/tig functionality.
biddy6,
Jan 3, 6:17am
0.6 Hard wire would be a better choice of wire, but you will need a gas bottle for that.Those old mig welders are a bit behind the inverters of today.
gsimpson,
Jan 3, 6:38am
How far you have the torch from the work affects things too. Try welding with a shorter arc.
shakespeare6,
Jan 3, 8:26am
Most likely the heat settings are tapings off the transformer. The wire feed supply is also fed off the selected tap and some have a linear converter circuit to allow fine adjustment of the wire speed (or at least the old one I have modified has.) What I have down in the lowest tap got a 1-2 ratio wound transformer ( good copper wound unit) and added that in series of the lowest output. Of course you need to add that before the rectifier. You end up with half the output on the lowest setting. You could use another transformer out of another old welder and use the high taping the ratio would be close.
marte,
Jan 3, 9:26pm
Thanks shakespeare6. That was sorta what I was thinking would be needed. Changing where it taps the secondary winding on the transformer. Does less windings on it mean less power?, just to be sure. I have a invertor stick welder, but the welds I want to do are really small fine welds. Too small even for the 1.5mm rods.
Using the 0.6mm wire with gas (Thanks biddy6) is the other option. But gas costs extra money and this would waste a lot of gas.Though not have flux to clean off would be nice. To setup for gas I would need extra parts to make up. These welders use a valve on the handpeice, which leaks, no gas solinoid on the machine.
I have TIG handpeices, I have not done much TIG work. Don't really like it. Takes too long and I can do the same job with a MIG anyway.
skin1235,
Jan 4, 6:53am
the other option is to use a brazing torch, . and learn how to weld with it properly - something most are incapable of doing today
a good brazing setup and a good welder can weld a split in the throwaway ali film roasting dishes,not that anyone would bother but it can be done by anyone with the right skills and gear
cabrio1,
Jan 4, 9:08am
I have the same problem with my welder. I've found the most effective way to weld this small stuff is tiny individual tacks. Make sure it's all clean , one small tack then reset for another one. Too much heat a wire otherwise. I've welded body panels from thin steel this way, takes patience and a bit time consuming but successful. As you get the feel for it you can make bigger tacks. Runs of weld, very difficult with this type of gear on thin material.
marte,
Jan 4, 11:46pm
I have to be able to hold the peice in place and tack weld it, then do a run over it.
Its not panel steel, though the heat setting I want would weld it perfectly in one run.
I used a friends minimig, same generic sort, and it would do this job perfectly. Their must have been something different with it though. I was really impressed with it at the time too.
He could never get it to run right, then I had a look at his setup and he had the earth clamped to then brake disc.
In saw a guy weld two coke cans together with a Hobson HHO gas torch once.
I noticed the Map/Oxy torch at Supercheap last week. I have a MAP torch and found out later its too fierce and is not MAPP gas anyway, gutted.
So it means buying a whole new setup and I am not interested in renting gas bottles off BOC as well.
shakespeare6,
Jan 5, 5:19am
Yes less windings on the secondary side will decrease the open circuit output voltage.
macman26,
Jan 5, 6:31am
Poster #9. You should never run welding current through bearings. Good way to stuff them.
marte,
Jun 21, 5:53am
Yeah, he kept yelling at the welder and shit. Am I'm saying" So you have plugged it into the kitchen stove outlet, and you do have a good earth?". Etc etc. Knowing that the power in the garage comes from a 20metre extension cord plugged in somewhere in the house. He saying "yes but I can't get this damn welder to run right" Which was weird as I had it running really good earlyer. So I double check about the earth and stove socket. And he's going "yes but what difference would it make anyway?. "
I could not see what he was doing, stuck down beside the wall and the car.
So we call it a day, its 10pm.And he says" we might as well anyway, they are getting sick of having to turn on the overload switch as its turning off the telly anyway.
Ah, he said it was "plugged into the stove socket" like I told him to do. And I look at where he's welding and notice the earth clamps connected to the brake disc.
Some people, actually a lot of them, tell them to do something and explain why and what damage they will do and for some reason they do exactly what you told them what not to do.
And then for some stoopid reason, they think its not their fault.
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