Different generators

[Stan]

Has anyone seen this site?
Stan

http://yananmotor.en.alibaba.com/product/50062391/50591788/Alternators/Permanent_Magnetic_DC_Arc_Welding_Generator.html

[Doug]

Can't tell you much without stripping one to see how it works.

Two thoughts how do you adjust the welding current?
Would the shock of striking an arc all the time not demagnetize the field over time?

[clytle374]

The box on top might be big enough for there to be some sort of control.

About striking the arc, NdFeB magnets aren't (my understanding)  nearly as prone to demagnetizing as others.  I think you need a very magnetically tight (air gap ect) setup plus a some heat. 
But again this is "my understanding"
 

[ZackaryMac]

For what it's worth
 I built a DC welder using a 13hp Honda engine and a 100amp Chrysler alternator, the old "square" style with external regulator (not used).
After about 30 3/32" 6011 rods, the thing still works, much to my surprise. I run the rotor at full voltage - 13.5v, as I have a second car alt to keep the lawnmower battery fully charged during use, as the rotor draws about 6amps - so it runs 100% all the time. I hope to correct this by regulating the voltage going to the rotor somehow, with a reostat that can handle a steady 70w or so, as it burns too hot actually.
After every 2-3 rods, I shut the rotor voltage off for about 5 minutes to let it cool. Poor alternator wasn't designed to run 100% dead short.

Sorry it doesn't have anything to do with these welders you were talking about...just thought someone might find it interesting.

[Doug]

You bring up an interesting point about All alterantors ( including ST heads ).
They have a high output impedence so they weld and don't fry in a short....
Try that with a DC generator and you will burn it out....