How to install and remove hand bushings?

AvatarBob

Registered User
Jun 4, 2016
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Hello. This is a very basic question but I haven't been able to find an answer on my own. How does one install and remove (if removal is possible) the bushings from the holes in hands?

These are the hands I have now, front and back, but I'd like to replace them with custom hands. If I can remove the existing bushings and put them on new hands created with the correctly sized holes to receive the bushings, then great. But I don't know to remove the bushings, or if that's even possible after they've been installed on the hands.

IMG_2885.JPG IMG_2886.JPG

If the old bushings can't be removed, I think that the following are the new ones I need, but I don't see how I would install them on new hands. They are for a Hermle 1171-890 tubular chime movement, if that's helpful to know. The hands will go on an Urgos 03121 movement, but I've confirmed that the old hands fit on both movements with a little squeezing or expanding of the hour hand's bushing's tube, so I think the new 1171-890 bushings should also work on the 03121.

HourHandBush6_5mmDia.jpg MinuteHandBush3_7mmSq.jpg

Thanks in advance for any insights.
 

Willie X

Registered User
Feb 9, 2008
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That little protruding rim, on your first photos, can be filed away a bit at the outer edge/side. Use a fine flat file with a "safe" edge. You will still leave scratches on your hand. You may be able to leave enough meat to stake, or peen, the hand back on.

If you have a lathe, it's usually easy to make the bushing shoulder a little deeper to allow a better stake/peen.

No lathe, just do the best you can and finish with a tiny bead of CA glue. A toothpick is a good tool to apply and spread the glue.

Make sure the minute hand is properly positioned for correct drop-off point at the hour, before the final step/s are taken.

Willie X
 

RJSoftware

Registered User
Apr 15, 2005
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Making hands and hand bushings is enjoyable but a bit of work.

First think you may notice is there is an over abundance of softer aluminum hands from quartz clocks. Totally no go for mechanical clocks. Hands should be made of steel. Because time adjustment is often done by turning minute hand with fingers.

Some people cut some really elaborate hands using scrap spring steel. It's not rocket science but certainly skill to admire. To top it off then the hand is heated to beutiful blue.

As to cutting the hand bushing, I start with some brass round stock and turn outside diameter first. I take a measure of square end of minute hand arbor between two flats parallel. I lock that measure on my caliper and then find a matching drill bit that fits. I drill hole through center with brass stock in collet and lathe assures center ( stock turns, bit held stationary). The lathe forces drill bit to drill center.

Then it's time to file the 4 corners. The file is small watchmaker rat tail file with 4 corners but it tapers to a point. What I found is even though the file is small to begin with, it needs to be even smaller. So knowing that I only need two sides to make one corner edge, I grind away the opposite side corner with diamond wheel dremel. Plus since the bushing doesn't have far to reach in, I only grind about 1/2 inch long from file tip.

This gives me a file with a small thin portion that I can file the 4 corners inside the drilled hole. The process is file-test-file repeat...

Also forgot to mention I deliberately leave a lip on bushing so brass protruding from hole in hand just above hand surface so I can peen bushing in center and lock hand to bushing, but I do this after I fit bushing on arbor and turn to 12: oclock position.

I use a round nose punch to peen in center of bushing. Just enough to grip. A little touch up filing and done.
 

AvatarBob

Registered User
Jun 4, 2016
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Thank you, RJ! I appreciate the details!
 

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