Info on my P&H welder?

[jfdmas]

hey guys, i purchased this old P&H ac/dc welder about 1yr ago for about $400. This was my first tig machine and my first time ever tig'n. Ive played around alot and researched and feel as if im doing ok now. I put this thing thru ALOT of heavy use and im growing scared that someday things may stop working do to age. Is there anyone that knows how to fix these foot pedals if/when they go bad? any kinda maintanance i should know about on these old machines to keep em goin strong?







and teaching myself to weld.


4in exhaust for my 800hp bmw





I realy love this machine regardless of its size/weight and i realy cant afford another machine if this one fails, so any input would be great. thanks guys.

[vicegrip]

PM sent !
I'm lazy today!
Call if ya want!!
Phil

PS:
Cool welds by the way!!

[vicegrip]

But with different plugs?
http://cgi.ebay.com/MILLER-RFC-23A-T...item41559c8c7d
OR
Like this (see along the top).
http://www.naxja.org/forum/showthread.php?t=999245
Either 15 ohms / or 20,000 ohms?
It has to match what ever is behind your pannel amp-controll.
The physical pedal is not important.

CHEERS
VG

[jfdmas]

thanks for the call phil, it was nice talking to someone that knows the history behind these machines.

i took some pictures of pedals and the inside guts so hope these may help out.

[SidecarFlip]

The cooling fan motor is as big as the motor in my wife's washing machine.....

[usmcpop]

Some of the old P&H pedals have this inside...

[vicegrip]

If that's your pannel ampurage control in the corner of that pick.....
then measure the ohms of resistance in the sweep of your pedal
(by using an ohm-meter) on your pedal-plug. {UNPLUGGED}

I'll bet it's in the 15 ohm range.
In which case the Miller RFC - 23 will be a suitable replacement.
.....This, if a much "rarer" P&H pedal can't be found.
Note: I live near the source and have never seen one yet.
Cheers
vg
.
.

[SidecarFlip]

Some of the old P&H pedals have this inside...

Without the cracked ceramic I presume?

[usmcpop]

Without the cracked ceramic I presume?

That's a fault line across Los Angeles...

[SidecarFlip]

Excellent answer.

Could be a fault line across Indiana as well........

[usmcpop]

We have a nuke plant here in VA not far from an earthquake zone.

[vicegrip]

Well .... in the right sequence of events,
your departure could be spectacular.!

[jfdmas]

i will check the resistance of the pedal this weekend while im at the shop. Still moving stuff around and cleaning/installing stuff. If we dont see any diodes or rectifiers then what could be inside this thing? where should i look to see?

[vicegrip]

A selenium stack should jump out at Ya !
look like this about a foot long.

Diodes like any of these.

vg

[jfdmas]

ughh, so my worst nightmare has accured to me. I have been doing a ton of welding lately and she quit out on me. I get a spark and no DC, or a spark and then a realy crapy arc. I ripped out the diodes and a few of them appear to be bad, however i cant cross reference the part numbers to anything. Is it critical that i get the same exact diodes to replace these with? also what is with the diode that has the extra wire coming out of it. thes 2 appear to be straight polarity while the other 4 apear to be reverse polarity diodes.

the 2 on the far left have leads coming off them and they attach to a circuit board as well. any one know what these are for? im not sure if i tested them correctly but both were open when checked with a meter.



circuit board


I checked the part numbers in digikey and came up with nothing.












Id love to replace all 6 if i can find suitable replacements. I love this machine and i need to keep her working. Ive got a Big turbo 418ci ls3 build that i need to finish tig'n up to get it outta my shop.