What's happened here..

[dnhb]

Dismantling a 'family' clock. Managed to remove the stuck-on ceramic dial without cracking it & found what looks like an inventive previous repair. Grateful for views on what might have happened back then & what the original part was.

[oldhippy]

I need to see the whole movement please photos of the back and front and between plates a photo of the case would also be good 

[dnhb]

36 minutes ago, oldhippy said:

I need to see the whole movement please photos of the back and front and between plates a photo of the case would also be good 

It's in bits now: hope the attached pics help. The back plate bears the words "....British United Clock Co Birmingham  England". Thanks for your interest.

[nevenbekriev]

3 hours ago, dnhb said:

Dismantling a 'family' clock. Managed to remove the stuck-on ceramic dial without cracking it & found what looks like an inventive previous repair. Grateful for views on what might have happened back then & what the original part was.

Nothing seems modified or not original. What are You concerns?

[dnhb]

10 minutes ago, nevenbekriev said:

Nothing seems modified or not original. What are You concerns?

In the top (original) photo there is a coil of wire between the plate and the lower wheel which I thought might not be original....

[oldhippy]

It is all original and you do not have missing parts.  

Those movement were cheap to make so they are rough and ready. To help with the action of the balance make sure both balance tips (points) are sharp like you would have if you sharpened a pencil you need a lathe to do this and a small Arkansas stone and a drop of oil. The two cups must be clean and roughness in side remove with a fine countersink and re-oil, don't have to much end shake.

Edited April 8 by oldhippy

[rjenkinsgb]

I suspect that may be a friction drive between the movement and the hands / motion works, to allow for time setting?

Something broadly equivalent to the cannon pinion friction drive in many watches.

 

[watchweasol]

Hi @rjenkinsgb  is correct hand set friction clutch, best not to dismantle unless the center hole needs bushing.

[nevenbekriev]

11 hours ago, dnhb said:

In the top (original) photo there is a coil of wire between the plate and the lower wheel which I thought might not be original....

The coil of wire is a spring that is there to press and create friction for the 'clutch' that slips when the time is set.

[dnhb]

Thanks for your advice, guys, which, as a newbie, I respect. However, please excuse my offering the following observations: while the spring is completely compressed, as the original photo indicates,  it shows no sign of expanding when pressure is applied to reduce the compression; there is no evidence of any torsional force; it is not uniformly cylindrical & its ends do not have the form I'd expect those of a manufactured spring to possess. To my inexperienced eye it looks just like a coil of wire that's been created to achieve the desired spacing between 2 components.

[watchweasol]

Hi. It may look like a coil but it is compressed enough to provide the tension to enable you to move the hands.

the coil is compressed via the bush under the plate on the arbour. In better quality clocks a three leaf spring is used in the same way again compressed via a bush. Bear in mind these were mass produced and lacked many refinements and in large numbers. Most probably ended up scrapped as the repair costs was more than the clock.   If you take into consideration the quality, the plates are poor the wheels are rough which is commensurate with mass produced movement.

[rjenkinsgb]

You won't see any obvious movement with it as it is - but if you apply a bit of force, you should find that the small pinion at the top end in the first photo can be turned relative to the large wheel, but with significant friction.

 

All conventional clock and watches must have some friction slip "clutch" mechanism. to allow the hands to be set without breaking the movement; without that clutch, the hands could not be set, other than by stopping and starting the whole movement.

These are some other examples, from a box of scrap clock bits I have; the first uses an overgrown cannon pinion style setup, with a sleeve that's been pinched or twisted slightly to make it grip the shaft - you can see the steel shaft through the slot in the brass sleeve.

The others are spring loaded, more open variants of the one you have:

 

[dnhb]

16 hours ago, rjenkinsgb said:

You won't see any obvious movement with it as it is - but if you apply a bit of force, you should find that the small pinion at the top end in the first photo can be turned relative to the large wheel, but with significant friction.

 

All conventional clock and watches must have some friction slip "clutch" mechanism. to allow the hands to be set without breaking the movement; without that clutch, the hands could not be set, other than by stopping and starting the whole movement.

These are some other examples, from a box of scrap clock bits I have; the first uses an overgrown cannon pinion style setup, with a sleeve that's been pinched or twisted slightly to make it grip the shaft - you can see the steel shaft through the slot in the brass sleeve.

The others are spring loaded, more open variants of the one you have:

 

Thanks for the education RJ. I did find, in line with your comment, that I could move the pinion & wheel independently & now understand why being able to do that is important to time-setting. However I remain convinced that on my clock the friction has simply been achieved by an ad hoc 'cylinder' of wire of the length necessary to achieve the desired effect: it is not a 'manufactured' part like the springs in your helpful picture.