Loose Centre Wheel Arbour

[mooseface]

I am working on an unidentified pocket watch movement believed to be Schild Freres circa 1895 (see my earlier post if you want to try to identify the calibre). It has a couple of problems with the centre wheel arbour. First of all, the arbour is loose and easily pushed out of the pinon. Secondly the arbour is slightly bent. Bearing in mind that I do not yet have a lathe or a staking set, what advice would you give me to fix this problem?

[watchweasol]

Hi  Try putting the arbour on a flat surface and rolling it with a little pressure  it may help in straightening it.  do it gently but firmly. What you are trying to achieve is a reforming of the arbour slowly,   As regards it being loose in the wheel  one can always use loctite. It is used when pivoting clock arbours when fitting the new pivot so I guess its a legitimate fix.  There are several types of loctite depending on what it is being used for so some research regarding the best type to use would be in order.       Cheers

[Marc]

Do not straighten that pinion, it's supposed to be bent!!!!!!

That is the canon pinion set up on a lot of old pocket watches. The bend in the pinion is to create the slipping friction clutch function to allow the train to drive the hands, but also allow the hands to be set without sending torque back into the train.

This has been discussed fairly recently but I can't find the thread, however have a look here for more detail.

[Klassiker]

1 hour ago, mooseface said:

the arbour is loose and easily pushed out of the pinon.

 

22 minutes ago, Marc said:

it's supposed to be bent!!!!!!

So not bent enough, then?

[nickelsilver]

It doesn't need much friction to run the hands, but if it's really loose it should be made tighter. For that you really need a staking set.

[mooseface]

1 hour ago, Marc said:

Do not straighten that pinion, it's supposed to be bent!!!!!!

That is the canon pinion set up on a lot of old pocket watches. The bend in the pinion is to create the slipping friction clutch function to allow the train to drive the hands, but also allow the hands to be set without sending torque back into the train.

This has been discussed fairly recently but I can't find the thread, however have a look here for more detail.

If the pinion is bent doesn't that cause the tip of the minute hand to take a sinusoidal path as it rotates and risk it interfereing with the other hands, or is the bend so small as not to matter?

1 hour ago, watchweasol said:

Hi  Try putting the arbour on a flat surface and rolling it with a little pressure  it may help in straightening it.  do it gently but firmly. What you are trying to achieve is a reforming of the arbour slowly,   As regards it being loose in the wheel  one can always use loctite. It is used when pivoting clock arbours when fitting the new pivot so I guess its a legitimate fix.  There are several types of loctite depending on what it is being used for so some research regarding the best type to use would be in order.       Cheers

I was already tempted to use Loctite but it just didn't feel right. Having said that spending a few hundred on a staking set doen't feel right either although very tempting :-)

 

 

[Marc]

25 minutes ago, mooseface said:

the bend so small as not to matter

Correct

[nickelsilver]

Since the hand turns with the center wheel (which runs true in its bearings), if it is set parallel to the dial it will remain that way. And even during setting, the shaft rides in the hole in the center wheel, which is the guide and is straight, so no problem.

Hold your arm up at a 45 degree angle, and hold a piece of cardboard parallel to the ground, now pivot around 360 degrees, the cardboard doesn't nutate, despite the dramatically bent part.

[mooseface]

33 minutes ago, nickelsilver said:

Since the hand turns with the center wheel (which runs true in its bearings), if it is set parallel to the dial it will remain that way. And even during setting, the shaft rides in the hole in the center wheel, which is the guide and is straight, so no problem.

Of course. I had not pictured it properly. Obvoius now but not at all obvoius half an hour ago. 

[watchweasol]

Hi Mooseface    Sorry I ballsed up there In 60 years never had one of those, Maybe about time I quit and retired, sorry.

[nickelsilver]

Hi Mooseface    Sorry I ballsed up there In 60 years never had one of those, Maybe about time I quit and retired, sorry.

Don't fret-I've seen a number of them and still space out and mangle my levers trying to get the canon pinion off before remembering 'ah it's the old one!' sometimes.

[nickelsilver]

Of course. I had not pictured it properly. Obvoius now but not at all obvoius half an hour ago.  [emoji38]

If it was a common modern style canon pinion and the long pivot of the center wheel was bent itwould be an issue, when setting.

[mooseface]

45 minutes ago, watchweasol said:

Hi Mooseface    Sorry I ballsed up there In 60 years never had one of those, Maybe about time I quit and retired, sorry.

No problem. Definitely not a severe balls up, and anyway, why quit while you are still learning . Just goes to show how much there is to know in the world of watch repair, let alone horology. I look forward to gaining knowledge from your sixty years of experience.

[mooseface]

While I have several experienced members on this thread, are any of you able to to indentify the calibre of the moevment. I origianlly posted that question, with pictures, here.

[mooseface]

Thank you all for your help in getting this watch back in working order. I thought you might like to see some pics of the finished result.

[Rustinbox]

On 6/5/2020 at 11:41 PM, nickelsilver said:

It doesn't need much friction to run the hands, but if it's really loose it should be made tighter. For that you really need a staking set.

Resurrecting this thread. I have similar situation - arbor is loose but not detached from the seconds wheel. Any good advice what and how to use staking set tool? Stakes or punches or maybe pin vice? Thank you!