century 117-070 replacing button diodes what amps?

admin

got another century 117-070 mig welder for cheep,sputtery weak.inconsistant.i gambled, from success on my new miller rectifier diode,i figured it would be the diodes they are the button type 12 of them.and they have no i.d. on them just red on one side and black other figure they are like a batt? pos+ neg_ on each of them right?red was up toward connectors and the plain side was against the heat sink there is a wire bolted to the heat sink,so i figure they are not the indvidual designated male female type.but -+ diodes.there a lot of them on ebay there rated at 35a and some 50a what does this welder use? it is a 90 amp mig .would like this for a helpers loner. backup leave behind the seat welder so i wont miss it if it ever got stolen,
Reply:here is the complete rectifier replacement  for that http://www.weldingandcutting.com/Pro...de=860-905-666Lincoln Power Arc 4000 Thermal Arc Fabricator 252 iThermal arc 186Thermal Arc 26 tigTweeko 200 amp spool gunHobart AirForce 400WP-17V-12R
Reply:would these work? on ebay 50 amp pos neg polarity 200v Attached Images
Reply:"Cars", why don't you just retrofit a rectifier like we used on our "Sidekicks" ? We know those work, and obviously the Century welder's original diodes did not hold up. You should post a pic, so we can see what you're dealing with.
Reply:yeah i wanted to convert it to our chinese heavy duty rectifier bridge type but its totaly different baffling.the century has no pos neg capacator just two ac wires from the transformers and a ground to on the heat sink not simple 2 ac in 2 pos neg dc out self explanatory like a bridge diode. this machine uses 12 button 3/8 round diodes on two  6- star shape configuration, not really worth putting too much effort in upgrading.just want to change the originals for new exact fit type.getting ready to by them on ebat 50 amps 200v each .thought this might be a good spare
Reply:well the 50 amp diodes were a success welds as good as a century 90 amp mig gets, no more of the erratic-pulsing and sputtering bead. i guessed on getting the 50 amp diodes vs the other choice 30 amp diodes. this machine uses 12 of these total.the ones i got from ebay are a little smaller in dia but had the correct thickness allowing good contact to the heat sink plate.what a nice deal for 12 plus dollars.hope this will help others, just dont make a mistake the 117 line of century migs. uses pos+- neg polarity diodes and the pos side is up, neg is down on contact with the heat sink plate.
Reply:Way to go ! It's fun fixing things that others would just throw away. You've repaired two and I've done one. We should open welding repair shops in our areas. My local repair guy is a real nice guy, but he didn't fix my machine.
Reply:Originally Posted by BradTNWay to go ! It's fun fixing things that others would just throw away. You've repaired two and I've done one. We should open welding repair shops in our areas. My local repair guy is a real nice guy, but he didn't fix my machine.
Reply:Hey Cars,  I need to pick up some of those diodes as well.  I only found 25 amp ones on e-bay though.  Can you direct me to the seller that you bought your 50 amp ones from. Thanks if you could,
Reply:If those diodes are about the size of an asprin tablet they are rated at 10 amps tops.Putting small diodes in parallel to hand more current does not work well.One or two diodes tend to handle all the load and over heat.IF YOU TEST EACH ONE YOU WILL FIND MOST ARE Ok.Dont pay 80 bucks for a new rectifier thats a rip off.An ohmmeter will find the shorted buttons.These diodes are worth a buck each at most.