Waltham Center wheel repivot project!!

[LittleWatchShop]

This watch (A Waltham 0 size) has been in my drawer for some time...must have bought it on ebay.  Started to repair it today and noticed right off that the center wheel pivot was broken and stuck in the cannon pinion.  It was easy to punch it out, so I have the reference for making a new one.

My plan is to turn down the post all the way to shoulder above the pinion and then drill a hole in the pinion and mount a new post.

Then I have to do some curvature adjusting to fit the cannon pinion.  Not clear how I will do that just yet.

No real downside because I dont have a case for the watch.  I must have bought it for a donor...just cannot remember.

 

Here is more detail on the model.

Edited March 2, 2023 by LittleWatchShop

[LittleWatchShop]

[LittleWatchShop]

OK, I have the old pivot removed and have turned a replacement.  What you see here is not final.  It is a friction fit, but I want to use Loctite to fasten it in a "reversible" way. 

I have Loctite 680 and 648 but not sure which is best.

 

Edited March 3, 2023 by LittleWatchShop

[nickelsilver]

648 is what I would use. Still good to have a light friction fit, but at least a "sliding" fit with no perceptible play.

[RichardHarris123]

58 minutes ago, LittleWatchShop said:

OK, I have the old pivot removed and have turned a replacement.  What you see here is not final.  It is a friction fit, but I want to use Loctite to fasten it in a "reversible" way. 

I have Loctite 680 and 648 but not sure which is best.

 

Excellent work. 

[LittleWatchShop]

48 minutes ago, nickelsilver said:

648 is what I would use. Still good to have a light friction fit, but at least a "sliding" fit with no perceptible play.

Super!  That is what I will use!!

_____________________________________________________

Done!

Edited March 3, 2023 by LittleWatchShop

[LittleWatchShop]

Here it is after clean and assemble with no optimization. 

_____________

Maybe I should start another topic but here goes.

I am making a 3D printed case for this watch since I was missing the case to begin with.

One thing I have never dealt with is the stem tube of a pocket watch.  It is important because it holds the stem and allows for the two positions (winding and setting).  I either have to create this function, or get a pocket watch stem tube insert.  Not even sure I am using the right terms here.

Edited March 4, 2023 by LittleWatchShop

[nickelsilver]

But how does the CP fit? The devil is in the details...

[LittleWatchShop]

1 hour ago, nickelsilver said:

But how does the CP fit? The devil is in the details...

Feels perfect. I got lucky.

[RichardHarris123]

8 hours ago, LittleWatchShop said:

Feels perfect. I got lucky.

I think skill, not luck. 

[LittleWatchShop]

2 hours ago, RichardHarris123 said:

I think skill, not luck. 

A bit broke...I was lucky it did not get stuck. Re CP, I went very slow and measured constantly.

[LittleWatchShop]

Well, an update.  I must confess my sin.

When I turned down the rest of the post before drilling and inserting the new one, I failed to notice the diameter of the pivot that rests in the bushing (the shoulder) was greater than the rest.  I illustrate what I missed below. The arrow points to the additional diameter that I missed.

So, rather than turn a new one, I stole the pinion and shaft from a donor (the wheel on the donor was broken in half).  This was not as straightforward as I hoped. The dimensions of the replacement part were larger and as a result, there was ZERO endshake (perhaps negative).  I had to turn down the part of the shaft that rests on the bushing to make it fit. 

Live and learn.

Edited March 18, 2023 by LittleWatchShop