Columbia AJ motor issue

[cosmo666]

I recently acquired a Columbia AJ side wind phonograph that was pretty much intact and original. One of the governor springs was broken in shipping so I could not test it until I got a replacement. Once that was fixed I wound it which worked ok but it would not hold the tension. I found that the worm gear that drives the governor was spinning inside of the gear that comes off the drive. After dismantling I saw that the worm gear fits inside the other gear with splines so they rotate in unison. unfortunately those splines are stripped. Can I,
1. JB weld the 2 together.
2. Solder the 2 gears
3. Nickle plate the gear with the splines to add some metal and press them together.
4. ?
All the gear teeth are in good shape and they are all brass. I know this is kind of long winded but I thought anyone that has worked on early Columbia motors has encountered this and be able to send me in the right direction. Thanks.

[JerryVan]

#2, Solder the 2 brass gears together.

[cosmo666]

Sounds like a plan. I was wondering, it looks like an intentional fail spot to maybe protect another gear or could they not figure out how to machine 2 dissimilar gears as one.

[JerryVan]

Sounds like a plan. I was wondering, it looks like an intentional fail spot to maybe protect another gear or could they not figure out how to machine 2 dissimilar gears as one.

If I understand correctly, the other gear is the bevel gear, correct? If so, then you're correct in that the bevel can't be cut while the worm wheel is sitting right next to it. There has to be clearance for the gear cutter to pass through the bevel. (Technically, it could be made with the 2 gears side-by-side, but way more difficult and not worth it.)

[cosmo666]

Yes, the other gear is a bevel gear. After messing with it a little longer it looks like that worm gear was made that way so it would only turn in one direction. I guess we'll never know. Anyway I'm going to solder it together and get this machine to play some music!

[startgroove]

The gears are made with a zero tolerance when assembled and it is quite unusual for the gear or shaft to become stripped. Just to be safe, look carefully for a tiny crack in the gear. If it is cracked and you solder it onto the shaft, there could be a hiccup every time it passes over the two teeth where the crack is. If it is not cracked, then disregard this message. Cheers, Russie

[cosmo666]

Thanks for the tip.

[cosmo666]

Just a note of caution to all you home repairers, the worm gear is a FIBER gear. What it's made of I don't know but don't put any heat to it. I recall reading something, maybe on this forum, awhile back that Columbia used a fiber gear in this area to quiet the machine somewhat. I don't know. Since the gear I have is ok I'm just going to JB weld it and should be good to go. Thank you for your time.

[JerryVan]

Just a note of caution to all you home repairers, the worm gear is a FIBER gear. What it's made of I don't know but don't put any heat to it. I recall reading something, maybe on this forum, awhile back that Columbia used a fiber gear in this area to quiet the machine somewhat. I don't know. Since the gear I have is ok I'm just going to JB weld it and should be good to go. Thank you for your time.

I was a little skeptical when you stated brass, but then I have seen brass worm wheels before, so...

Happy you discovered it before applying heat!

[startgroove]

Yes, me too. I was questioning it when you said you could solder it in your number 2 option. Now that we know it is not a bronze gear, JB weld makes more sense. Not to be picky, but the proper terminology for the pair is the worm screw and worm wheel. That helps in discussion of which is the problem. Cheers, Russie