Interesting Balance Staff Issue

[jdrichard]

I had to make a balance staff for a 16S Hampden PW. Cutting the balance was the first step.

The next step was to stake on the roller table, that also holds the balance.

I then had to mount the balance on the roller table. Because I had to cut the material off to take it off, the only option was to glue the balance arms to the table. I used some krazy glue and on the arms, Aligned the balance and then staked it on.

All good except one issue. I forgot to ensure the impulse jewel was at 90 deg to the balance arms. It is under one of the arms which means if I need to re-shelac it in: very difficult. So next step will be to true the balance and then work the pivots down to the right size. The last step will be to stake on the safety roller and then adjust and Mount the hair spring.

 

Will report if it works and if it does not work and I need to start again. All good....learning to step back and look at the big picture as well:)

 

 

Sent from my iPhone using Tapatalk Pro

[jdrichard]

Update. When I was truing the balance the balance unglued front the roller table so I cleaned everything up and re-glued it. Now I need to wait until the glue sets before bending anything


Sent from my iPhone using Tapatalk Pro

[jdrichard]

Sent from my iPhone using Tapatalk Pro

[azkid]

Cool. Looks like good progress!

 

Asking pardon for my ignorance... [emoji4] Normally one "rivets" the balance on with a little brass washer type thing? (Except friction fit balances). Does the CA hold well enough? I have several broken Elgin balances I could fix this way. Thanks [emoji4]

 

PS: I wonder if CA accelerator spray would work?

 

Sent from my Pixel 2 XL using Tapatalk

 

 

 

 

[digginstony]

Somebody likes his pocket watches [emoji3]
Azkid is quite right. The balance wheel is attached using a staking set. Start with an appropriate hollow rounded tip stake and finish with a hollow flat tip stake. Great care to be taken not to distort the arms whilst hammering. GLUE of any sort does not belong in a watch movement [emoji852]
The roller table can easily be removed and adjusted to 90° with the correct tool. I'm away at moment but will post picture of tool on this thread as soon as possible so you know what to look out for. I purchased mine of ebay years ago but should still be possible to find. It's basically a chuck that fits into the base of your staking set and has a set of separate jaws that fits over the balance arms, onto the back of the roller table and using a stake you tap the roller table free. This tool is an absolute, when dealing with double rollers.


Sent from my SM-T585 using Tapatalk

[khunter]

I've never seen a roller table that sits between the balance and the staff shoulder, are you sure this is correct? You might want to check some other staff diagrams to make sure before you proceed..

[khunter]

4 hours ago, azkid said:

Cool. Looks like good progress!

 

Asking pardon for my ignorance... Normally one "rivets" the balance on with a little brass washer type thing? (Except friction fit balances). Does the CA hold well enough? I have several broken Elgin balances I could fix this way. Thanks

 

PS: I wonder if CA accelerator spray would work?

 

Sent from my Pixel 2 XL using Tapatalk

 

 

 

 

Most balances are riveted on, but there is no washer. The rivet shoulder of the staff is slightly undercut so it will spread out when stuck with a round faced punch, then the rivet is flattened with a flat faced punch. There are lots of videos online showing the procedure, including Mark Lovick. 

DON'T USE GLUE IN A WATCH!!! (Except maybe the crystal)

[azkid]

Most balances are riveted on, but there is no washer. The rivet shoulder of the staff is slightly undercut so it will spread out when stuck with a round faced punch, then the rivet is flattened with a flat faced punch. There are lots of videos online showing the procedure, including Mark Lovick. 
DON'T USE GLUE IN A WATCH!!! (Except maybe the crystal)

Thanks for that! I have seen some videos but must have missed the part about the staff itself being deformed. I feel a bit daft for my questions.

Sent from my Pixel 2 XL using Tapatalk

[clockboy]

15 hours ago, jdrichard said:

Sent from my iPhone using Tapatalk Pro

I have made that mistake a few times. You should only remove balance staff material. The method I use is to remove a little of the balance staff rivet then I use a Platax tool too finally drive the old staff out. The problem you will have now is getting the balance poised. For this reason using glue is not a good idea. If it was me I would make another balance staff with a fatter shaft and then fit using the normal fitting procedures.

[rogart63]

Looks a little different this balance wheel. It's sitting on the roller table . Other balances is riveted on the axle. So i guess there is no other option but to glue it on. Or make a new roller table. 

i would probaly use loctite instead of superglue. A hard setting one like loctite 603 or something similar? 

[khunter]

34 minutes ago, rogart63 said:

Looks a little different this balance wheel. It's sitting on the roller table . Other balances is riveted on the axle. So i guess there is no other option but to glue it on. Or make a new roller table. 

i would probaly use loctite instead of superglue. A hard setting one like loctite 603 or something similar? 

I believe the roller table isn't installed properly, it should be under the shoulder of the staff, not on top. It's a standard American pocket watch design. NO LOCKTITE!! LOL

[rogart63]

26 minutes ago, khunter said:

I believe the roller table isn't installed properly, it should be under the shoulder of the staff, not on top. It's a standard American pocket watch design. NO LOCKTITE!! LOL

Maybe. But almost sure Jdrichard is doing the same as the original balance staff. Not an expert on pocket watches and hasn't seen a lot  PW balances. But see what you mean. Will have to wait and see what JD says  

The balance staff should look a little more like this? Roller table from the bottom and the balance wheel riveted on from the top.  Then the hairspring collet on the thinner part. 

 

Edited February 19, 2018 by rogart63

[khunter]

Here is a crude drawing of a balance staff and where everything goes. This is for a double roller, a single just doesn't have the second step at the bottom. The roller table and safety roller are both friction fit on a taper. The cutaway view of the balance rivet shows the undercutting required for riveting. 

Edited February 19, 2018 by khunter

[khunter]

There is a caveat, a friction fit staff, as in the later Hamilton 992B and quite a few Walthams is simply that, friction fit into the balace. There is a tapered collet fixed inside the balance hole and the staff is simply driven in or out, after removing the roller table of course. The collet provides the spacing required for the roller table. Special stakes and anvils are required to do it safely. 

[khunter]

Here's a photo from my staff catalog with dimensions for Hampden staffs. It's not a blueprint but it gives an idea of the different major measurements (in mm)

[digginstony]

This is the best tool for safely removing the roller table. Mines by C.E. Marshall. Which quality wise I rate as good as Kendrick & Davis.
With the hairspring removed, you place the jaws over the split balance arms.
The jaw ends fit onto the back of the roller table.
As seen, the jaw shafts are threaded and rotated in the chuck (want of a better word)
The jaw diameter is reduced to give a better fit.
A stake is placed over the lower pivot onto the staff and given a light hammer until the roller table loosens.
Anyone interested in old pocket watches should keep an eye out for this type of tool. They do come up on auction sites



Sent from my SM-T585 using Tapatalk

[digginstony]

I have made that mistake a few times. You should only remove balance staff material. The method I use is to remove a little of the balance staff rivet then I use a Platax tool too finally drive the old staff out. The problem you will have now is getting the balance poised. For this reason using glue is not a good idea. If it was me I would make another balance staff with a fatter shaft and then fit using the normal fitting procedures.

Ideally the staff should be cut and removed using a lathe. Failing that, this is the best tool for removing the staff and avoiding serious damage to the split balance wheel.
I've no idea what a Platax tool is ? A picture would be greatly appreciated [emoji16]

Sent from my SM-T585 using Tapatalk

[khunter]

A platax tool is basically a fancy staking set, they come up on eBay every now and then, and cost a fortune!

I have both tools you have pictured, and they work like a charm. Pretty cheap investment if you do staffing frequently. 

Edited February 19, 2018 by khunter
Additional thoughts

[digginstony]

Ideally the staff should be cut and removed using a lathe. Failing that, this is the best tool for removing the staff and avoiding serious damage to the split balance wheel.
I've no idea what a Platax tool is ? A picture would be greatly appreciated [emoji16]

Sent from my SM-T585 using Tapatalk

Poops wrong instructions. Will do a couple of pictures.

Sent from my SM-T585 using Tapatalk

[digginstony]

Here we go. Balance staff remover with correct instructions [emoji16]

Sent from my SM-T585 using Tapatalk

[jdrichard]

Looks like the glue does the job and the weight is in the center on the balance so it should not impact timing


Sent from my iPhone using Tapatalk Pro

[jdrichard]

Looks a little different this balance wheel. It's sitting on the roller table . Other balances is riveted on the axle. So i guess there is no other option but to glue it on. Or make a new roller table. 
i would probaly use loctite instead of superglue. A hard setting one like loctite 603 or something similar? 

Good suggestion. If the balance falls off, I will clean off the Krazy Glue and replace with loctite 603


Sent from my iPhone using Tapatalk Pro

[jdrichard]

Here I am sizing down the pivots.

Sent from my iPhone using Tapatalk Pro

[jdrichard]

Here is a crude drawing of a balance staff and where everything goes. This is for a double roller, a single just doesn't have the second step at the bottom. The roller table and safety roller are both friction fit on a taper. The cutaway view of the balance rivet shows the undercutting required for riveting. 

It is not a traditional balance staff. The roller is shaped like a top hat where the balance staff actually fits on the top part of the hat. It is intended to be friction fit i think.


Sent from my iPhone using Tapatalk Pro

[jdrichard]

Sent from my iPhone using Tapatalk Pro