Hi all, I just acquired a complete set of pocket watch timing washers covering size 6 thru 18. Boy are they tiny. They are all made by C&E Marshall and are metal, and the vials still contain lots.
The box has a chart and when I add one washer to a timing screw I have to add the same to the opposite screw. On that chart it shows that by adding one washer the movement slows down by a given amount.

For example if I add 1 number 36 washer in 24 hours the watch looses 4 minutes. That seems excessive doesn't it?

I'm amazed that you can play with the timing that much. I got the washers so I could wind in some of the timing screws that right now are turned out from zero to say 3 turns as the movement was running to fast for the regulator to compensate for.

Luckily I've only got about 4 movements that I'll install the washers on.

Roland, You said;
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I got the washers so I could wind in some of the timing screws that right now are turned out from zero to say 3 turns as the movement was running to fast for the regulator to compensate for.
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Those "Timing screws" are Mean time screws. DO NOT "wind them in", they Belong where they are.

The small amount they are "wound out" allows for precision adjustment of the watch timing!

Hi David. So those are the screws at the end of the yoke and then 90 degrees to those, so 4 in total.

I thought that those were the only screws that you did adjust either in or out for timing and that the rest were for poising the balance.

You may remember about a year ago an Elgin BWR that ran way too fast. I ended up adjusting only the yoke screws and it now runs very close to RR in 4 positions.

That is one of the movements that I wanted to add the washers to that would then bring those 2 screws back in closer to the balance.

So do I have the use of timing washers wrong and they are only meant for the other balance screws?

Roland.

Roland, the timing washers work fine for what you want to do. I would put them on the first two pairs of balance screws nearest the mean time screws on the yoke so you do not mess with the temperatyure adjustments. Then as you have noted the watch will slow a little and you can compensate for that by using the mean time screws. I use the Hamilton chart for figuring out the mean time screw adjustment

Thank you David, very handy chart.
On this chart I assume for example that 1-full on 4 screws = 6 seconds/hr can go either way. Turn in and gain 6 seconds, turn out and loose 6 seconds.

Again thank you.

Roland.

David thank you the wealth of info I learn from your post. Is there any way you could email me a copy of this chart so I can download it. I have no found out to down load from the posts.

Thank you
Gene Buffard

genebuff@charter.com

Gene, I tried unsuccessfuly to send the picture to your e-mail address; genebuff@charter.com

to save pictures directly from a posting in IHC185;
1. Put your cursor on the picture and right click.
2. Put your cursor on "save picture as" in the grey window and left click.
3. Put your cursor on the folder with a green "up" poiinting arrow at the top right of the listing window and left click a few times until "desktop" appears in the "save in" wiondow.
4. Hit "save"
5. The picture is now downloaded to your desktop.

David : I always read your comments with great interest. And I learn a lot. I'm still trying to understand the dynamics of balance movement.Would it be true to say that whenever timing washers are added the balance should be poised.
Thanks again for all the great information you so freely provide our group. Regards,, Don

Don, Timing washers are used to slow down a watch that is running too fast. They extend the "length" of the timing screws ever so slightly which has the same effect as letting down the pendulum weight to slow down a clock.

Timing washers have the opposite effect on "poise". If more than a few pairs of timing washers have to be added, the watch loses it's "poise" (balance) and has to be re-poised.

During re-poising, some will use a timing washer to correct the balance. I prefer to slightly undercut the Balance screws, because (for me) it is usually more effective to regulate a poised watch that is a little fast.

David: I'll try to be more specific, I have a old s18 Omega that runs 12 min fast in 24hrs,it was 1.5 hrs slow until I tightened the cannon pinion. I've checked several positions it's very consistent. I believe the hair spring is wrong . The meantime screws 4 are all screwed into the rim. If I add timing washers should they be added to the meantime screws.I'm trying to avoid repoiseing, that's beyond me and my modest tools right now. Don

David : One more detail I have tried de-magnitizing this movement, no change. Thanks again for your thoughtful advise.
I believe a little knowledge is dangerous to watches and other mechanical things.