Main spring

[Speedy Builder5Participant @speedybuilder5]

Smiths Mantle Clock

[Speedy Builder5Participant @speedybuilder5]

I have been asked to look at a Smiths Manthe clock dated 1 sept 1950, just 4 years after I was born ! Both the main and chime springs were overwound, but there doesn't seem to be enough Zing in the main spring to make the escape wheel to turn. If I take the escapement off, the wheel turns OK. I have cleaned and sparsely oiled all the bearings, but still not enough to make the escapement tick back and forth even without a pendulum.

Has the Zing gone from my spring – and can I get it back ?

BobH

[Michael GilliganParticipant @michaelgilligan61133]

More likely that the clock needs a good clean, and possibly some re-bushing.

Even a tired old spring should have the zing to move the thing

MichaelG.

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P.S. … a few close-up photos might help with our attempts at remote diagnosis

[Speedy Builder5Participant @speedybuilder5]

It all looks in a clean condition although the mainspring releases itself with a bit of a 'jump' every now and again. I assume this may be due to old oil causing the coils of the spring to 'glue' together, but before I take that out and clean it, I thought a few questions / thoughts may be in order.

Here are some photos, but don't know if they help. The clock is marked SMITHS Enfield and on one corner is marked HF. The wooden case is dated 1/9/1950

BobH

Edited By Speedy Builder5 on 08/07/2019 11:25:22

[Martin KyteParticipant @martinkyte99762]

Mainspring 'jumping' shows the spring is need of cleaning and relubricating. Do be carefull if you intend taking it out of the barrel although you should be able to do a reasonable wash out with solvent. Relubricate with a dribble of motor oil on the edge of the coil, it will work it's way in. You need to ensure that all the pivots are lubricated too with clock oil.

regards Martin

[BazyleParticipant @bazyle]

They must have made millions of those movements – I've got a couple sans case and some other bits. Look out for worn pinions where you might need to move the corresponding wheel along a bit.

I've always wondered why the plates are covered in that pinhole pattern. Was it some technique of flattening the raw stock?

[Michael GilliganParticipant @michaelgilligan61133]

Thanks for posting the photos, Bob

I see that Martin and Bazyle have already replied helpfully

From what I can see at that resolution, the movement looks relatively unworn

As for the pivots: They need to be very free-running, especially towards the escapement end of the train … Tip the movement onto its back, and then over to its front; all the arbors should move freely and 'click' as they contact the plates.

You are probably right to suspect gumming-up of the mainspring.

A strip-down & clean would almost certainly be effective.

MichaelG.

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@ Bazyle … Yes, the dimples are evidence of a flattening process.

[KWILParticipant @kwil]

Early TV and radio chassis were also similarly dimpled, not only flattens but more important, it stiffens the plate. They used very thin sheet steel in those days.

[Speedy Builder5Participant @speedybuilder5]

I suppose its too late to go back now !!

[Michael GilliganParticipant @michaelgilligan61133]

Well done, Bob

I suggest you watch this before re-assembling: **LINK**

https://youtu.be/ep4zBK2rmnk

[ sorry, couldn't find the embed link ]

MichaelG.

[Speedy Builder5Participant @speedybuilder5]

Thanks everyone, its been an interesting afternoon and have been talking to Meadows and Passmore. It is more than likely that the spring is weak and another is on order – Well, they do sell springs !

Watched the video thanks Michael and found this one too. **LINK**

I never realised just how clean bearing had to be, I suppose its the problem of working with an Austin 7 for the last 44 years!

BobH

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