Seeburg sparking contact ...Problem fixed .

I am once again working on a Seeburg . Its one of the AY models . I have noticed this on other seeburgs of the same type too . This one is worse than any other i have seen .
The machine works . Its the top set of contacts on the front of the mech . 3rd set of contacts down on that stack . Each time those 2 contacts either close or open they spark , flash and a trace of smoke from the contacts .

Ken, those are the contacts that add capacitance to the motor cuircuit during handling/scanning. Some sparking is normal. However if excessive it means that they are pitted and making contact on a small area of the contact face. With machine --unplugged-- lightly file of pitted areas, or just clean with an alcohol soaked business card (or similar rough paper).

Also make sure that there is adequate contact pressure when the contacts are closed. There should be slight wiping action here.

Rob

Thanks for your help . I will take those points out where i can see them and polish them right . I was concerned there was a bigger problem .

Thanks !

Ok its fixed . Here is what was done . First i removed the white bulb deflector thing over the contacts so i could get at the points stack better . I removed the 2 long screws holding the stack on and pulled it outward a bit .

I carfully pried off the rectangular brown part on top of the stack off . These go over 2 hollow tubes where the long screws go down into ... I removed the first contact blade and marked it #1 . I continued prying up & off those rectangle pieces and blades till i got down to the pair that was sparking . I layed the rectangle parts down in order so i could get them back on in order .

The contacts were very pitted . I did not cut the wire from the blades , i worked on them still hooked up . The top contact of this set was worn into a slight bowl shape with uneaven edges . The bottom contact was not so deformed but it has a ridge around it . I used 600 grit emery paper to rub across the bottom contact till the pits and outer ridge was gone .
I used a very fine file to carfully file the bowled in contact till it was flat . I then used the 600 paper to remove the file marks and slightly round the edges .

After that i used a piece of kinda rough thin paper held against the file to rub and polish the contacts to very shiney .

There is no sparking at all on these points anymore .

Thanks for the help on this .

Well, Ken,
Thanks for posting this--but--
I think you "over worked" here--I do that job in about 2 minutes. If burnt, I use a point file, to remove the "burn/pit", then a burnishing tool to smooth them. I "hold" the contacts together with long nose pliers. I do not dis-assemble the stack of contacts. IMHO, "sandpaper" of ANY type, should never be used, as "sand" embeds itself in the silver, causing more problems--
Note any contact that has lost 50%, or more, of it's silver material, should be replaced.
Ron Rich

I have what is called a points file here . It is way to rough on silver contacts , i would not use those . If you are smashing down on the contacts with the pliers and running a file in between standing there in front of the jukebox ... you cannot see what is hapening . The soft silver contacts would get filed off crooked with sharp edges and flat surfaces .. then the points would not close flat and only on one edge of the contact pad .
Emagine someone not real coordinated doing that and runing all of the contacts .

Most contacts have minimal damage that can be fixed with fine emery paper . If you burnish the points afterward there will not be any kind of dirt on the points . I have never heard of emery paper grit staying behind if you clean it off .

As usuall 10 guys in a room will do the same thing different .