Seconds Hand Fitting Tools Advice

[chrisbuxton27]

Ok so I have a cheap Chinese hand pressing tool but I'm not happy with its build quality. It's fine for fitting hour and minute hands but there is play in the shaft which becomes worrying when fitting the seconds hand. As we all know how susceptible the seconds pinnions are to breaking. Also a lot of the vintage omegas are spring loaded or have a jewelled bridge at the rear. Is there anything available for supporting the jewel whist pressing the seconds hand on with a precision tool. I've been using a minute wheel attached to the base of the hands pressing tool to support the jewel and praying while pressing the hand on... Any thoughts or tried and trusted methods please

[Marc]

I actually use a staking set to install hands.

 

For the hour and minute hands I use a hollow flat stake, choosing a hole size that just fits over the minute hand arbor for the hour hand, and one that just fits over the seconds hand arbor for the minute hand, and pushing down gently by hand (no hammers). That way the stake comes up against a positive stop when the hand is in place and the tendency to push the hand too far down the post is eliminated. As a result there is almost always sufficient clearance between the hour hand and the dial, and between the hour and minute hands, the hands always go on square, and the only time any adjustment is necessary  is if a hand is bent out of its correct shape.

For the seconds hand my staking set has a stake with a plain, flat, brass tip and a plastic ball on the top (so designed for pushing by hand rather than hitting with a hammer).

 

As far as supporting the other end of the seconds hand arbor, this has never been an issue for me. As a rule, if you have to apply a lot of force to get the hand on to the post then its probably the wrong size hand. It should really only require light pressure to get it to seat, but nowhere near enough to damage the supporting bridge or jewel. If the movement has an indirect driven centre seconds hand with a tension spring bearing on the end of the arbor then this should flex enough to allow the shoulder of the arbor to contact the jewel or bridge for support without any harm coming to the spring.

 

The exception to this is chronograph centre seconds hands. When you reset the chrono the seconds hand rotates back to zero very fast and comes to a sudden stop. Because of the length of the hand and the speed of rotation, inertia is likely to cause the hand to slip around the post when the post stops at zero so unless the hand is a tight fit, it would be constantly going out of alignment.

For this reason  you should always use the correct movement holder which will have the proper support for the lower bearing built in to it.

 

Basically, use the right movement holder for chronos, and a light touch for everything else.

[Lawson]

This is a very good question Chris.  I'm looking into the same thing.

Using the standard Horotec hand fitting tools is fine for basic movement; but as I move on to more and more expensive movements (some these days over a thousand dollars), I'm not happy using the standard tools for fitting the hands.

 

I was considering this tool from Horotec, and any input from the seasoned veterans would be most appreciated...

 

[chrisbuxton27]

Thanks for the detailed reply Marc. I've just bought a staking set with a red nose on the top and a brass pin at the base. Will give it a try. As for the chronos it's not always viable to purchase a movement holder for every repair job. Think I will invest in a 7750/1164 as its a very popular one.