Sterling M5 restoration (Updated 1-23, new pics)

[Mac]

I just checked it... All of the lock tabs are bent straight up and out of the way...It just doesn't want to go anywhere. The nuts read "N-07" on one side and 18T on the other...None of those on ebay- suggestions as to where I may find one? I'm not going to cut these off until I know I can replace them.

[Westgate Thunderbolt]

I don't know what the 18T number is. The N-07 is the nut size. The lock washer number will be W-07. They are still available. I go to a bearing supply house for them. Give your local bearing supply house a jingle.

Like holler stated earlier, it may be left hand threaded. By the nut number you just gave, I don't think it is though. Left hand threaded nuts have an NL classification not just N.

[landmobile]

Do you know what year yours is,

Not really sure, all I have to go by is the motor ID:



Since it was originally a 2 phase motor I"m guessing the siren dates from the twenties or early thirties. It was rewound for 3 phase operation prior to my rebuild, but I don't know when.

There is also "8038" stamped on one of the stators.

[holler]

Mac's was probably made the in the 40's-50's, since his has the Peerless ball bearing motor.

Chris's siren is much older since it has the Howell sleeve bearing motor, complete with those damn oil wicks that would petrify after 60+ years.

[Mac]

The motor is now completely apart. The armature looks pretty good and so does the rest of it.... Is there anything I can use to clean it off (just to make it look a little nicer), or even repaint it?

[holler]

Awesome, so how did you get the lock rings off? Care to share?

As for the armature, you can clean the segments with a brush seater stone, and then go down between every single one of the grooves with a toothpick and scrape out the carbon and other crap that has accumulated.

Post some pictures of it too if you don't mind.

[Mac]

Sorry it took me a little to get around to this.

I rotated the shaft until it was in the position it locks up in (it spun freely most of the way around, but got stuck in one part. It was having difficulties starting \ running well, I'm sure this was part of the problem). I then drilled a small hole into the side of the nut over the slot in the threads (as to not damage them), and continued to drill it out larger and larger. Once the hole was very large, I took a large steel wedge and mini-sledge and gave it a few whacks until it spun free. Pulled the whole thing out, stood it on the ground so it couldnt spin, and gave the other one a few whacks until it came loose.

Once it was all apart I popped the bearings out to see if they were the problem- they were. They grind and catch at one part.. I soaked them in gas to clean them off and they still aren't smooth. Both bearings are different- one reads "L-07" and the other "N-07", just like the nuts... The bearing supplier said these aren't bearing numbers and don't make sense to be on the bearings. I just noticed a 4 digit long number (smaller) on the inner ring- could this be the right number? If I can't find replacements, what should I use to re-grease them? What is a good bearing grease for sirens in general?

Next problem I found, I'm sure contributing to the poor running of the siren- only 1 brush worked. Of the 4 brushes, 2 were seized above the commutator, 1 was broken and seized, and 1 worked ...okay. I removed the brush holder assembly and completely dissembled it to the last screw and washer and polished \ smoothed every piece with a dremel wire-wheel.... used 400grit sandpaper to clean in the springs. They are all reassembled now (no picture) and work perfectly... but I still have 1 broken brush and the other 3 could stand for replacement.... Am I going to be out of luck finding them? They have a word on them I can't make out with a large "43" under it.

[holler]

If I were you, I would repack the bearings with a good grease and reinstall them. For future reference, that 4 digit number on the inner race is the bearing number.

As for the brushes, get the dimensions and go to a motor shop. Give them an old brush and see if they can find one for you. If all else fails get some slightly oversized brushes and work them down with sandpaper until they fit. Also, put that brush holder ring back in the EXACT position it came from, that is where you adjust the angle of commutation. I hope you have reference point to line it back up to.

Also, clean the commutator with a seater stone and clean between the copper bars with a toothpick. Also, don't run that motor on 240 with no load, because it will overspeed.

I just hope you can get that brusholder ring rotated back to the right spot, look for the mark made by the set screw. Seat your brushes on 120 with no load also.

[Mac]

Will do. Where do I get a seater stone & what type of grease should I put in them? I only have White Lithium at the moment- not sure that is thick enough.

I was worried about taking them off and not being able to figure it out- but after I took one off to take a look, the rods actually have pitted \ raised lines where the brush holders clamp together- so they pop back exactly as they were.... Then the whole assembly itself had 2 setscrews that were well tightened and left some good marks- I hadn't even thought about those needing to be the same spot though.

[Mac]

I've had some down time as i replaced everything in my sand blasting cabinet, but I'm back up and running! Here is a small update

Progress:

Brush holder mounting ring \ washers. Cleaned, Sandblasted & primed (Sticking with primer- I love the color)


Re-assembled


End of housing blasted clean


Bearing \ grease caps blasted (& primed- no photo)


Primed


New wire vs. old wire


Re-screening the housing end


Everything back in the exact same spot


Done & waiting for grease stem