I've noticed something on some '92 model 18s Walthams and wonder if anyone would have the answer.Some of them have a small hole drilled in the balance wheel recess, right alongside the hairspring stud.I checked on the Model 1892 research website, and there's no mention of it, as I said some have it, some don't.Just wondering why that hole is there and for what purpose. Thanks!, Ted.

The later model 1892's had a notch drilled in the side permitting working the balance screws without removing the Balance wheel. Very dangerous to try. Not recommended unless you are ready to replace a broken Balance staff.

I have had good luck with doing it that way. You just have to watch that the screws are not to tight. If they are then you can take the balance cock out and do it that way.

Regards,
Larry

Ted, it is mentioned on the Model 1892 site in Movement Variations as "The Groove"

Hi.
I think Ted is meaning the hole visible in this image from the same source.
http://www.model92.com/_/rsrc/...2020641%20CPRCr1.jpg
I've been wondering about that myself, but found no solution.

Regards, Krister.

I see, well that's a hole different story.

ewe funny

Maybe the hole is made to facilitate stopping the balance during adjustment?

Krister is right, I didn't mean the notch on the edge, which is to reach the meantime screws.I just can't figure out what that hole is for.I wonder if it's a locating hole for a dowel pin, or was for machining purposes.My 21J Vanguard and 17J Appleton Tracy have it,my 21J 845 does not.

I just noticed that the CPR that Dave pictured doesn't have the hole either, but that's a high serial number '92.Must have been dropped by then.

quote:

It is one of the two (2) locating dowel pin holes for the bottom balance jewel cock that is affixed to the backside of the train plate by a screw

This subject was discussed a couple years back right here on IHC185 !!

https://ihc185.infopop.cc/eve/f...523984677#9523984677

regards,
bb

Thanks Buster, I was looking for that as my 75 year old memory percolated back to mind a discussion of that once before. The bottom bridge for the balance wheel needed that in the early models.

Thanks to all, it never even occurred to me to search this site,I thought I was the only one to even notice it!I got a good kick out of the "oil hole" ideas...Ted.