About 35 amp bridge rectifiers

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It it possible to use several (equal or greater than 4) 35 amp bridge rectifiers altogether in a generic AC buzz box for DC stick welding? where I'm from inverter and DC welders don't exist. 7014 and 6011 rods don't even exist either and I'll I got is an AC buzz box and the only electrodes I can use for it are 6013 rods; I am sick and tired of AC stick welding. If all else fails, then I may have to use batteries and jumper cables for my 6010s and 7018s, which I want to use, but am still unable to use them. I also heard that 6010/7018s penetrate better. P.S It is nearly impossible for me to buy anything off the internet atm.
Reply:Yes you can hook them in parallel as long and they all have a low value resister in series with them. So each rectifier gets it's own 0.01 ohm resister wired in series with it then that rectifier/resister unit gets wire in parallel with all the other rectifier/resister units. But wait there's more, ideally all the rectifiers should be mounted to the same heatsink. This plus the resisters make the rectifiers share the current more evenly so one rectifier doesn't get too much current going through it and die. But wait there is still more, if you want it to really work like a DC welder you need to put a reactor choke in series with your rectifier contraption. The reactor choke is a big inductor that works to smooth out the current flowing through the arc. It an be made by rewinding an old microwave oven transformer. What size wire and how many turns are determined by you welder's max amps and the size of the microwave oven transformer. Do able? Yes. Practical? No. I just have to ask, if you live somewhere where DC welders don't exist, why can you get 6010 and 7018 rods, when they need DC? And yet you can't get 6011 and 7014 rods that run on AC.Also the car battery thing really only works if again you have a reactor choke in series with it to smooth out the current changes from variations in the arc length. Just batteries alone won't do much.My "collection":Homemade Stick WelderVictor O/A TorchAC 225Ideal Arc 250HF 90 Amp Flux CoreHF Mig 170Solar 2020 Plasma CutterPower i-Mig 140EHarris O/A torchHF Dual Mig 131140STAlpha Tig 200x
Reply:The reason why 6010s/7018 rods are accessible, but not the welders made for DC stick welding is because the rods are pretty cheap and easy to mass produce. I wonder where I can buy resistors from, which I thought about getting them somewhere. Not sure if any of these small, electronic stores have them. Oh yeah! I did see how a choke can be made with an MOT plus 8 gauge wires in that Instructibles site. It's difficult to get welding equipment in a developing country that isn't a generic AC buzz box. The electrodes here are also generic, so chances of me finding the Lincoln Excaliburs that I heard so much about are very unlikely.
Reply:So you're limited to 35A bridge rectifiers?  From scrap car parts?Can you get power diodes and make your own rectifier?You're not going to be able to buy a power resister like what Iain P has suggested (though that will work in theory) that won't fry itself, and a resistor of such a low resistance is more commonly known as a shunt.  You'll have to wire wind your own.  Four feet of 14 gauge copper wire will yield 0.01 ohms of resistance FYI (not that I'm suggesting that is a good value as a starting point).
Reply:The OP is really talking about building a high amperage DC power supply with multiple bridges. I guess that can be done with the good issues mentioned above. Don't forget to have some large capacitors somewhere in the circuitry to smooth things out.Miller Millermatic 252Miller Syncrowave 200Liincoln AC-DC 225Victor O-A Set
Reply:Originally Posted by gnm109The OP is really talking about building a high amperage DC power supply with multiple bridges. I guess that can be done with the good issues mentioned above. Don't forget to have some large capacitors somewhere in the circuitry to smooth things out.
Reply:Originally Posted by Iain PI've never seen output caps on a constant current stick welder before. I see them in constant voltage Mig welders, but not stick welders.