I have a Syncrowave 500, really old model (1979) and I *finally* got all the stuff to run while I was away, set it up and starting using it this morning. My high frequency start isn't working. I did my best to clean the spark gaps as Agtronic recommended, and set them to 8 thou like the manual and machine say, but still nothing. I can't hear anything like normal simply because the machine is too loud (the fan). I assume I can replace the tungsten points or something, but before I do that, is there something else I should try, or something I can check to pinpoint the problem more? How high should I adjust the high frequency intensity? I really don't want to deal with scratch starting all the time, I don't even know if that's possible on aluminium.

 

the fan on my sync 200 doesn't turn on until the machine starts to heat up
is it supposed to be on all the time on the 500?

 

Not really sure... I could always just disconnect it to check I guess, or put a switch in.

 

Call miller tech support...they could probably give you a good idea of what usually goes wrong on those so you're not chasing electrical gremlins for days.

 

The fans on the older machines always run. They don't have the fan on demand feature and yes they are noisy and even worse once you get a circulator hooked up also.

 

I'm really not all that concerned about the noise, my stereo in the shop is pretty good. I was more commenting that I can't hear any of the hiss/buzz noise, looking for another way to tell if the HF is working.

 

Do you have the switch for the high freq set correctly? It does have 3 positions one being OFF. If the switch is in either start or continous then you should be able to see arching across the points when the foot pedal is depressed. I haven't read thru all the replys so if I missed something don't get upset. Will the machine scratch start with the foot pedal hooked up and depressed? One thing is good and that is the machines are resonably cheap to repair compared to a newer machine with all the digital boards. I had a dialarc years ago and I had a pigtail pull off. Found it myself.

 

I do have the switch set right, I tried start and continuous. Tomorrow I'll try popping the HF panel off and watching the points with the pedal pressed. Scratch start works just fine, I did a few linkages today scratch starting, but I'd prefer to have it correct. Thanks for the help, seems like the HF is a problem on the older machines but I'm not getting too many replies anyway :/

 

So I fixed the problem today... kinda. I got some info from Miller and traced the problem back to the HF timer board, PC2 on this machine. A new one costs $475! So I figured the stuff in this machine can't be too complicated, and I pulled the board out to check it out. I was right, pretty damn simple, and I found a scorched relay





So I cleaned it up and put it back in, HF worked with the pedal (I could hear it distinctly) but once I struck a real arc it stopped working on the next one. I found a local place I can get a relay for 25 bucks, but after a better cleaning and reinstall, it's been working flawlessly all day.

 

yea my older miller had the old style "ice cube" relays in it.. Same thing happened with me except with high frequency start only. Cost a whole 6 dollars to fix

 

Just the start? What happened, the timer chip went? It's amazing how simple this thing is, next thing is to add a thermostat or something for the fan.

 

just the start. that was it.. I donated the machine to a vo-tech anyways