Vincienti & Cie mantel clock movement - damaged wheel repair help??

[rjenkinsgb]

Hi,

I'm hoping to repair a friends late 1800s French mantel clock movement (Vincenti & Cie, diameter ~90mm).

This has lost some teeth  - or a chunk - from a wheel on the first shaft that runs from the strike spring barrel.

 

(Looking at that photo, I think it's ready for a service regardless.) It was generally working, but stopping at random intervals. I discovered the damaged wheel while investigating that. The dust & fluff may have saved it from worse damage!

 

I bought a large box of old clock wheels from ebay that appeared to have some very similar parts in it; that also arrived today.

 

There are a few wheels and parts in it that appear to be out of one of these specific movements, but I don't think there is that exact one - one very similar visually, the same distance between pivots, but it's possibly slightly larger I believe. No way to be sure until I strip the movement down and can measure them.

 

Failing a miracle and that being correct, my "Plan A" was to try and find one of the same pitch and same or very near diameter from the scrap parts, and use a segment of that soldered to the near side of the original damaged wheel. There appears to be just enough clearance from the end of the barrel to do that without any interference, plus it's a reversible change - if the owners ever want it properly restored, the solder can be cleaned off.

Plan B is to adapt the spare HP movement to the clock case, and keep the original movement separately? It would mean swapping the dial, bezel & other parts, which I'd rather not do if possible; my preference is also service the spare movement and just keep that as a last-resort backup.

 

Any suggestions, better repair methods or anything at all helpful very much appreciated!

Photos of both movements are in my other post in this section, relating to compatibility between makers.

Robert.

 

[watchweasol]

Hi. Can you post a picture of the backplate as there may be a makers mark on it.  The problem you have there is that a previous repair has failed the insert that was soldered in has broken away. The wheel needs replacing hence the makers name and pictures. By knowing the maker etc we may be able to find a wheel. Ihave a collection of scrap clocks.  The repair that has broken is a standard repair if such a wheel could not be found so an insert is fitted. As this wheel runs directly from the barrel there is a great deal of torque for such a repair to last for long and ideally be replaced.    So plenty of pictures and the makers name of mark please.

[rjenkinsgb]

Hi,

it's the first four pictures in my other thread, here:

 

[rjenkinsgb]

[From Watchweasol, in the other thread]

Measure the distance between the pivots and the pitch of the teeth  I might have one as I have a drawer with some french clock bits in  

----

The wheel outer diameter is 23.8mm, 72 teeth (including the three missing).

Rolling it over a piece of carbon paper, one full revolution appears to be 75mm. Thickness 1.08mm.

The pinion has 12 teeth and is 5.6mm diameter, over the peaks; 5.6mm long.

Total tip to tip length 34.27, the inner ends of the pivots measure 30.38

Shaft diameter 2.5mm, pivots 1.06 at the support end and 1.41 at the wheel end. The wheel is set about 0,5mm from the pivot shoulder.

 

Now I have that wheel out, the solder remnants are very obvious on the side that was against the plate. I did not know of that method, though it does not look good for a gear with high forces and shock loads, as that one experiences with the strike mechanism stopping dead at the end of each sequence! Would it have been silver solder rather than tin-lead??

(The approach I was thinking of trying was to take a large section of a similar pitch wheel, eg a quarter, and use it as a long "splint", centred on the damaged part at the side of the original teeth, so the stress was distributed over a large area).

 

As I understand it, the owners had this clock serviced at a jewellers about 10-12 years ago.

I'm not impressed! The pivots appear to have been greased, with something quite heavy? It smears on the plates. One of the springs looks filthy. When I was letting them down before dismantling it, both did a kind of shudder when part unwound, as if they were gummed up and only released when a lot of force had been removed - despite looking like they are dripping oil when I removed the lids.

 

I don't know what the proper lubricants actually are?

I guessed when I was doing the smaller movement, using molycote on the arbours and barrel walls, with 9020 on the pivots and a small amount of that, a couple of smears at opposite sides, on each spring coil end, before fitting the barrel lids.

 

 

 

 

 

 

[watchweasol]

Hi   It looks in a bit of a state (filthy). These clean up very well.  I use. Few dabs of a special grease for the springs, if I can remember it name I will let you know. The general lubrication usually use windles clock oil reputedly the best. Be careful of the pivots on these clocks they re glass hard and will not stand any rough handling. I will be in my workshop this after noon so will have a look see.

which bit of Sheffield are you at, I lived in Tadcaster and did quite a bit of work in Sheffield [Edgar Allens] and a few down Brightside, Rotherham and Conisborough. Meadowhall was a Saturday shopping, now in the North of Scotland Fraserburgh.

you will need a  mainspring winder to remove the springs for cleaning, have a look on the the net there are plenty of good DIY ones to make.  I made two myself that work very well.

[rjenkinsgb]

I'm in Worksop; I just use Sheffield online as it's a more recognisable city for people on international forums.

 

I've already serviced a smaller (82mm) Vincenti movement I got by mistake, thinking it was the same as the 90mm one based on the ebay photos:

 

I also picked up an appropriate size mainspring winder a while ago, which I used for the one above:

 

I admit I'm not sure of the correct way of using that - I wound the springs then bound them towards one side with stiff copper wire to hold them coiled until I transferred them to the barrels...

(I also recently got a similar design one in pocket watch size).

 

I've just found a Moebius lubrication chart that includes clocks etc.

Looking through that, it looks like 9020 is the correct oil for the lower load parts, plus D/5 (equivalent to Molykote DX, as I used) for the spring arbours.

Surprisingly (for me), they also recommend that for the gear train - so the grease on the plates may have been the correct stuff.

Their chart says 8200 for the actual springs.

(I'd prefer to stay with one make as far as practical, to avoid confusion between equivalents).

 

[watchweasol]

Hi Robert. Worksop was a regular haunt, machine at Panderol. Foundry that made railroad ties. Done well with the winders, there are lots for sale but don’t have the bits which is a pest. As there are no shells or spring retainers like the Ollie baker that’s the way I do it as well..   you will be ok with the lubrication, everyone has there own favourites just follow what the chart recommends, you obviously know what you are doing. 

[oldhippy]

To me it looks as if that wheel has been repaired in the past and the block of teeth that were soldered in have come out. In that box of wheels if you can find a wheel with the same teeth count and pinion count if every thing is the same you might be in luck, if not but the teeth count are the same cut out a piece of the wheel and solder it into the original and tidy up making sure the teeth are the correct height and spacing and depth and pitch try in for running free. When it is finished you shouldn't be able to hardly see where the block has been soldered in. 

[watchweasol]

Hi Robert.  Had a look at the bits I have, 90 cm clock by ADMougin strike barrel missing, size between plates is 30.36mm, the arbour is 2.3 mm , wheel diameter  31.2mm,  from thpivot ends  35.1 mm      Teeth 78.  Pinion leaves 12    As the tooth count differs  it’s a non starter I am afraid.. what I would do is to undercut the slot where the teeth are missing to a dovetail shape and them if to can find a segment the same size nd pitch  solder that in. Being dove tailed it will give a better hold regarding the rotational torque and be less likely to pull out. Once done cleaned up and polished it should be almost invisible.

[RichardHarris123]

I haven't done this before so I bow to your superior knowledge @watchweasolbut I  don't think there's enough material left to dovetail.  Could a piece be soldered in and a thin plate soldered on to add to the mechanical strength, as per my crap photo. The green highlight is the plate. 

[watchweasol]

Hi Richard if the edges of the cut are filed back to form a dove tail the the new piece  cut and filed to the same shape and pressed on fron the side then soldered it will work ok and can be finished cleanly. By fitting an additional piece on the side would look unsightly and not look very professional, not only that the additional piece would have to be cut and filed to shape additional work.

 

[RichardHarris123]

That makes sense, thanks. 

[oldhippy]

By the time you have cleaned it up with needle files and made the bottom level you will not have much left to play with, remember once you remove you can't put it back, if you have a good tight fitting block and both are nice and clean so flux will flow so will the solder and it should be enough to hold, no don't put a plate on the side as already been said it will look unsightly.

Edited March 22 by oldhippy

[Dell]

10 hours ago, RichardHarris123 said:

That makes sense, thanks. 

I have a couple of scrap French clocks I will have a look tomorrow to see if I have the appropriate wheel .

Dell

[rjenkinsgb]

Ok, I've found a wheel in the box of junk that has the same pitch but slightly smaller, as a donor for some teeth.

I stretched a section of it by pinching two of the spokes until the radius matched the damaged wheel, then cut a piece out and did a lot of filing.

It's in, it looks OK, but I do not trust it to be long term reliable in that particular wheel, as it effectively gets a hammer blow through the gear train every time the strike mechanism stop arm drops in to the pinned wheel & locks it up dead. I'm going to add a strip on the side to reinforce it.. Not pretty, but soft solder is removable if a better repair is ever done and no one is going to see it for hopefully several years - then possibly just me..

 

"Stretched" donor wheel:

 

Very close to the same curvature:

 

Spot the insert!

 

The solder is actually flat, the lumpy appearance is a camera effect.

 

Edited March 22 by rjenkinsgb
typo

[RichardHarris123]

Let us know how it runs, once reassembled. 

[oldhippy]

Is it meshing with the wheel? 

[rjenkinsgb]

Done! I added a small curved brace to reinforce the joint - I checked with my friend first, they said that was OK.

Trying it with just the barrel and two relevant wheels, it spun freely so I've fully rebuilt it and it's now working fine. I tried giving the strike barrel a half turn wind before I built up the dial side and it ran smoothly for around ten minutes before running down, so it looks to be fine under load as well.

I'll be going to put it back in the case tomorrow.

 

Thanks for all help and advice.

Back to watches now; the springs in these clocks are frightening!

[oldhippy]

Good and well done it's not that easy. You want to take out and English fusee clock spring, French clock springs are nothing. 

[rjenkinsgb]

So the movement was returned to home yesterday afternoon, and my friends who own it are delighted it's now running as is should.

(I've not got the whole clock in, as when I was far enough away to see the full height, too much of the room was visible and I did not want to invade their privacy like that).

 

[oldhippy]

That is very nice. You need a lot of space for that.