Bought a new to me Airco Dip/Stick 160 multiprocess welder

[H80N]

What I meaneed by across the contactor you have 3 poles on the top half 3 on the bottom Springs in the middle. I thought the top ones should be powered and the bottom ones should only have voltage when the trigger is pressed on the gun. Mine read voltage on top and bottom without trigger being pressed

You asked for advice but chose to ignore it when given.....

You're Just Not Listening....



Sorry if we wasted your time it seems your mind was made up ahead of time regardless of input

I can only hope that you do not hurt yourself or anybody else

[Hondacivic247]

https://albany.craigslist.org/tls/5576651935.html

[Hondacivic247]

This miller shop master 300 looks like a good deal as it's got a wire feeder, can you mig tig and stick on that setup? It's 1000 bucks with all gear pictured. Link below

[Hondacivic247]

What I meaneed by across the contactor you have 3 poles on the top half 3 on the bottom Springs in the middle. I thought the top ones should be powered and the bottom ones should only have voltage when the trigger is pressed on the gun. Mine read voltage on top and bottom without trigger being pressed

[H80N]

I would say they do, they have a rubber nipple on the top that I was assuming would let go first before the can explodes but maybe that served as a way of filling them?

TOTALLY inadequate for the massive overheating and gas overpressure that can occur nearly instantaniously when fed AC or DC polarity is reversed

Modern caps usually have an "X" stamped into the top of the can... weakening it so it will split and vent the gas BEFORE it reaches dangerous pressures



Note: on this failed cap the can is balooned with the top split

Lacking such safety features the old ones will usually go off like a shotgun shell

Remember... you are dealing with 50 year old technology

[Aeronca41]

Sorry-can't tell from the pics about the sliding metal shunt, nor what you mean about the voltage readings on the contactor (which I still do not believe has anything to do with the problem you're chasing). Don't understand what "across the contactor" means. And all 3 poles have to read the same voltage-they are all connected in parallel by the big copper "finger" busses on the line and load sides. They parallel the 3 contacts to get enough current carrying capability.

[Hondacivic247]

Really doubt any pressure relief on 1977 vintage beer can Electrolytics......

OF COURSE THEY LOOK FINE...They only look bad AFTER they BLOW...

I would say they do, they have a rubber nipple on the top that I was assuming would let go first before the can explodes but maybe that served as a way of filling them?

[Hondacivic247]

The contactor is a 3 pole 240v 30-40 amp but on the inside part were it lists 24v 50-60c the 24v is 24VDC and not AC correct?

[H80N]

The caps also have a pressure relief valve on the top I noticed the other day, the caps do look perfectly fine . I'm going to unhook the diodes tonight and test them and make sure there not toasted.

Really doubt any pressure relief on 1977 vintage beer can Electrolytics......

OF COURSE THEY LOOK FINE...They only look bad AFTER they BLOW...

[Hondacivic247]

Is it possible that the sliding metal shunt somehow shorted out against the iron piece that goes over the low and high voltage windings?

[Hondacivic247]

http://m.ebay.com/itm/262462114465

[Hondacivic247]

Does this look like the same contactor I have, it's used but only 20 bucks. Mine says 240v on the side

[Hondacivic247]

Should I be getting voltage across the contactor relay when the trigger isn't depressed, I just thought of this cause when I tested the voltage it read both sides without the trigger depressed

[Hondacivic247]

The caps also have a pressure relief valve on the top I noticed the other day, the caps do look perfectly fine . I'm going to unhook the diodes tonight and test them and make sure there not toasted.

[Aeronca41]

I'd really like to see you disconnect the existing caps and power up the machine and see if your wire feed motor comes back up to speed. If you have a bad diode or some connection issue that is allowing AC onto the caps you could ruin your new ones. Not something you want to have happen. I would sure love to see the power to those caps on an oscilloscope. The sparking at the contactor is likely a symptom rather than the cause of the problem. Something is loading that circuit down in a big way.