Do welders lose power over the years?

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I mean the machines, not the guys using them.I was doing some stuff on the weekend with my trusty old stick welder. Mostly butt welds on 5mm thick stuff. Just mild steel, nothing fancy.I was using 6013 rods 3.2mm and had the amps way up. I didn't seem to be getting any penetration and the rods were sticking.I switched to 2.3mm 6013 (and lower amps). The welds looked better, but I would have rather done the job with 3.2mm rods for deeper penetration.It's a while since I've welded thicker stuff, but I don't remember having problems before.So could my welder be losing it?NB. I'm not a trained welder. The only stuff I've learnt about welding I have learned here
Reply:We had a MM251 here at work that kept getting weaker so we replaced it.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:mate , i have heard of welders doing this ,it could also be all your connections and leads if they are old , slowing the current , or something inside the machine . what sort is it ?
Reply:I don't know how true this is, so, risking propogating a myth...I always thought that a welder would last pretty much forever.  That's why I like the old stuff, but when I expressed this to another (much older, potentially much wiser) weldor, he said that, over time, some welder's transformers start to experience decay in the coating on the coils and that this can affect the welder performance...He gave a bunch of scenarios about when this is likely to happen...if you let lots of dirt build up on the transformer and can't keep it as cool...if you over-tax it by running it way beyond its duty cycle...if it sits in really bad environmental conditions...Sam's comment above suggests that simply adding up all the increased resistance from nasty connections might cause similar results.So, if this is wrong and a weldor's myth, maybe someone will stroll by and correct me on it.Smithboy...if it ain't broke, you ain't tryin'.
Reply:smithboy , the tafe instructor also told us that from over using the welder and exceeding its duty cycle it will eventually lower the duty cycle and power of the welder , i dont know if this is true or not just what i have been told
Reply:I have never experience a welder getting weaker.  However, along the lines of what Smithboy suggested--I have an old Black an Decker Grinder.  A couple of time the field had to be replaced because of over heading. The symptom was lose of power.  The field paper wound field and would break and get brittle down due to high heat.
Reply:Yes, I think electrical components, i.e. - capacitors, transformers, etc., do wear out over time from heat or heat cycling.John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:Well, I am sure it could happen, but with that said most of all of my stick machines in the shop are 40-50 years old.  Never had a problem at all with them.  Infact don;t let me see an older Lincoln for sale around here cause unless the price is unrealistic it as good as bought.  I think it depends on how well its taken care of as to the longevity of the machine.  Most anytime I start noticing a difference in the machines welding performance I cut the cable ends back a couple inches and clean the connections, and they always seem to go back to welding like a new machine.I'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:Thanks everyone.Sam, I can't remember the brand. Something or other 'Easyarc'. It's just an a handyman's machine.It's always been under cover and the climate here isn't extreme.The leads are as old as the machine. At least 15 years. I'll have a look at them and lop a few inches off each end.Scott
Reply:The open circuit voltage can drop substantially when a machine is older/in need of repair.  This is one of the primary causes of sticking.  Nearly every ESAB machine in our shop has experienced this at one point or another.
Reply:Your electric company sometimes lowers the voltage and that can make a big difference...
Reply:My answer is no..We have a Lincoln Idealarc thats been in service since the late 50's..And it still runs like brand new..So I say no.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Yah, most of the peeps doing quick jobs with their engine driven welders use very old welders. They run like a charm. They sell them and get very good prices too. Overheating could lead as said to the peeling of the coat and thus reducing performance, so it will also depend on the initial quality of the machine...I´d vote for the no, in average working conditions...seen too many 50´s machines work perfectly and owners very satisfiedMy Babies: HF Drill pressHF Pipe Bender3   4.5" Black and Decker angle grindersLincoln Electric PROMIG 175that´s it!
Reply:But what about these MM251's that are used 20hrs a day?  They don't have a 100% duty cycle so they're bound to give up eventually, right?DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:Originally Posted by elvergonI´d vote for the no, in average working conditions...seen too many 50´s machines work perfectly and owners very satisfied
Reply:Semiconductors (rectifiers, FETs, SCRs) will decrese in efficiency over time; especially when constantly hot. MIGs and TIGs all have these components. Transformers will short a winding or two over time. Their laminted cores get loose. The cores CAN be clamped tight and welded to lock them together.The main reason that new motors fail and are smaller: old ones are BIG and they are also inefficient power producers. New ones produce the same power in half the size using less wattage. The newer ones run HOTTTT since they are small in size and cannot shed the heat they produce.
Reply:Hey Scott , after you clean the ends of your leads , try blowing the dust out of the machine. It might not be letting the machine cool off correctly. Ive also seen the older machines run well .
Reply:I'll take the casing off (after disconnecting it from the power) and check for dust.So the lead ends definitely need replacing.Then I was thinking it would be handy to have longer leads (save me moving the machine so often).It may make sense to buy some new, longer leads. Unless longer leads will cause a power drop?
Reply:If you go longer, also make them thicker diameter (lower AWG number)I use "anti-ox" on all connections on recifiers, transformers, outputs, contactors to help keep the corrosion to a minimum. It will not cause resistance as some think.
Reply:That's interesting. I would have thought thinner for longer.What's 'anti ox'?
Reply:Anit ox is a paste/gel that prevents oxidation.  You can probably get a squeeze bottle of it at a hardware store in the wiring section.  And, yep...you need thicker cables to go longer distances at the same amperages.Smithboy...if it ain't broke, you ain't tryin'.