Hi. New to the group here and I was wondering if there was any device out there that might be able to reduce the amperage on my Lincoln AC-225 welder beyond what its lowest setting is. My goal is to be able to get away with welding thinner metal than what it can do already. Ive used 1/16 rod and the lowest setting on the buzz box, which I think is like 40A but it just blows holes in whatever Im doing.
Ive heard the company Eastwood claim that its "stitch welder" uses some kind of "reducing diode" to reduce the juice but I dont know what that is exactly.
I dont know if even what Im asking will work anyway, because it could be possible a 1/16 rod, which I think is the smallest there is, might not even be able to strike an arc below 40A.
I know the mig/tig option is really the best way to go for what I need, but Im kind of on a budget right now and just weld on occasion around the house. Thanx.
If you have 40 feet fo cable coiled up on the machine you get an inductance which effectively reduces the amperage output but it isn't a predictable amount. Also makes tools stick to the cable pretty well, not exactly a good thing. The AC225 is a fine machine but your asking it to do what it isn't intended to do.
Good luck,
No warranty that any of this will actually work. If you half wave rectify the output from your machine you will have DC at half the amps. This will require a rectifier with an average foreward current of , say, 40 or 50 amps giving some safety factor, and assuming the machine stays set at a low setting. It will require a peak reverse (or inverse) voltage of about the open circuit voltage of your machine. This will be installed in series with the cable of the machine. Assuming you use the electrode cable the cathode should be toward the machine (arrow of the diode points toward the machine), This will give straight polarity (DCEN) for less penetration. Disadvantages- the open circuit voltage also goes down by half. This may make starting difficult. Half wave DC from 60 cycle has 16 ms between the half waves, this may make the arc unstable. If this happens adding inductance may help. A few turns of cable around an iron bar is a start.
Be advised that semiconductors that fail at large currents may result in arcing or fire. You should protect yourself against this by at least keeping prototypes on a fireproof surface.
Have fun experimenting
Bill
To mount resistance of steel inox wire, second Ohm's law and resistivity.
to see hyperphysics.phy-astr.gsu.edu/hbase/electric/resis.html#c2
Bye
G. Lopes
SC - Brasil
I know maybe continuing this convo is probably kind of nutty, but I'm just curious if I can pull a rabbit out of a hat and gett away cheap on this one.
If you all wouldnt mind entertaining me a little more here, I was thinking perhaps a (variable) resistor in series on the electrode end might help my situation. In the old days that's what was used to reduce amperage before modern dimmer switches to control the amp setting on incandescent lightbulbs.
Would anyone happen to know the ac voltage (rms) that comes out of my lincoln? I think that should help me determine what wattage resistor I need, if this idea is even doable or if can find a reisitor that hearty. .
Thanks for the patience in all this. Any thoughts on this are welcome.
Maybe I'm thinking wrong on this one, but stick welders are CC machines, Constant Current. This means that no matter what resistance is placed in the circuit, the amperage is not going to change, within expected variances. I don't think a simple resistor will work, but I'm not exactly sure how a rheostat works either, so maybe someone could chime in and enlighten us...
gls
I converted my old arc welder into a tig welder. I added a high freq box and a full wave rectifier for DC. I use silicon controlled rectifiers on the 220 input to the transformer so I can control the output current from zero to the max I set the welder for.
Hi All!
Don't know whether this is relavent or not, but several years ago, I bought one of these 'stitch welders'. They replace the tongs on a normal 'Buzz Box' welding set. You put the welding electrode in and once you strike an arc, this contraption 'vibrates' the electrode 'in and out'! It's a bit like 'breaking the arc' technique, but hundreds of times faster than you or I could do it! Strange as it sounds, once you got used to this thing vibrating away in your hand, it was quite effective for welding thin gauge material with MMA!
Regards
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