Techniques for regulating 8 day clocks?

[Bill241]

I’ve been working on some vintage Swiss alarm clocks and desk timepieces with 15 jewel 8 day hand wound movements. These are 50s-60s era Imhof and Looping clocks- robustly built, terrific quality and as cheap as chips- can you even buy things like these now? I remember seeing these nice little clocks disappear in the 80s in favour of cheap quartz examples. 

When I service these I try to put in a new mainspring where possible (Cousins sell some of the Imhof ones for less than £3) but even then, I find the timekeeping can be a little variable- sometimes gaining to begin with, and then losing time towards the end of the wind. I guess this is the effect the fusee and chain was designed to counter, but I am trying to figure out how best to regulate it. 

My first thought was to let it run for four days, and then regulate as finely as possible at that point- hoping that the gain in the first four days would be countered with the loss afterwards. This assumes that the loss of torque from the spring is perfectly linear over the 8 days, and even if it works, the clock will only be working exactly to time at one point in the cycle. 

Is there a technique to all this or must I simply correct the time every couple of days? 
 

Thanks,

Bill
 

 

[oldhippy]

How are you cleaning the movements. What oils are you using. £3 for a new mainspring that is cheap I'm wondering if they are a poor quality. Another good make is Swiza have you repaired them. 

[Bill241]

I strip them down and clean off accumulated gunk and dust, then peg the pivot holes to remove congealed oil. When I buy these, they have often stopped or run sluggishly due to this.
 

Then I clean the parts in my Elma Super Elite (rinse 1, Elma 1:9 and rinse 2, distilled water). The third rinse is in IPA in a sealed container in an ultrasonic (not the pallets). I use Molycote DX on the barrel arbor pivots and winding/setting works, HP1300 on the centre wheel and third, then 9020 on the fourth, escape and balance wheel pivots. 941 on the pallet stones/ escape wheel teeth. Before the rebuild I demagnetise everything. 

Admittedly the first replacement spring was rubbish and slipped as the bridle isn’t a separate riveted section, just the spring bent back on itself at the end. The second one is doing better. The amplitude is very good in all cases, and the beat error negligible (well below 1). 

I’ve seen Swiza clocks but have never worked on one. I think they are pin pallet? The Looping 811 is my favourite as logically constructed and almost silent in operation. I can never usually get on with mechanical alarm clocks as the ticking is too loud! 

[oldhippy]

Try using Windles clock oil for the mainspring and arbor. A good pocket watch oil on the train and a good watch oil on the escapement, just a touch on the pallet stones and that will work around the escape wheel teeth.   Molycote DX is to be used on things with a heavy load which is not for clocks. Yes Swiza do have a pin pallet movements but they are very good movements they come in 30 hour or 8 day mostly with alarm but you can also have them in just a timepiece. 

As you are using a watch cleaning machine you should use a recommended cleaner and the correct rinse. I always used L & R. 

Edited October 13, 2023 by oldhippy

[Bill241]

Thanks, I certainly will get some Windles. And I will pickup a Swiza.
 

I tend to regard these travel alarm clock movements as a large pocket watch, and use the appropriate oils. 

I’m not sure about the alarm works, however. What’s the best procedure there? 

I have an Elma Super Elite cleaning machine, from 1959, which still works perfectly. It came with the original instructions which say to use 1:9 in rinse 1. I don’t use the petrol as suggested, as I work in a confined space and value my eyebrows. I’ve always used isopropyl alcohol as a final rinse for all parts other than those with shellac to dissipate any trapped moisture. But I will obtain some L&R. 

[oldhippy]

I've had and used a few cleaning machines including Elma a good little machine. To avoid damaging parts held by shellac clean them in Ronsonol lighter fluid it is harmless to shellac, have a small pot with a screw on lid as it evaporates very quick.  

[Bill241]

I read your advice in a post a while ago and clean the balance in lighter fluid kept in an essence jar.

[JohnR725]

On 10/12/2023 at 5:31 AM, Bill241 said:

My first thought was to let it run for four days, and then regulate as finely as possible at that point- hoping that the gain in the first four days would be countered with the loss afterwards. This assumes that the loss of torque from the spring is perfectly linear over the 8 days, and even if it works, the clock will only be working exactly to time at one point in the cycle.

It would be nice to have a picture or a better description of what you're working on. The reason is I noticed to use the words pallet stones versus Penn pallet escapement? The reason I ask is that this is a nicer eight day clock it's basically an eight day pocket watch. Possibly with a standard lever escapement. In which case you could use a timing machine the same as used in watch repair.

Then the assumption of what the mainspring will do is problematic. A lot of what the mainspring will do is determined by how was manufactured and the curvature it has. Usually mainsprings will have what's called the back curve and a lot of the stun is to live in their eyes the force that it produces. But with manufacturing techniques the way they are we tending a lot of variations in the shape of the spring which is going to translate to variations in power.

Plus if this is a standard lever escapement and you properly adjust things it should be more immune to amplitude variations. This is why when you look at the specifications for lever escapement watches they will actually have the specifications of fully wound up versus 24 hours later you should be within a range.

 

On 10/12/2023 at 11:10 AM, Bill241 said:

2, distilled water

You might increase the number of rinse to two of them versus just one. Typically with solvent-based cleaners the first was a cleaner followed by two separate rinses and somewhere in the discussion group for discussing the water-based cleaners it was suggested by others that you want to do something similar and have a second rinse of water before going to your isopropyl alcohol. 

 

 

[Bill241]

I’m currently working on a Looping cal 51. It’s a really lovely quality item and is also a barometer and thermometer. 

I’m not sure if the brass ‘star’ wheel in the alarm mechanism is meant to be lubricated? 

[JohnR725]

30 minutes ago, Bill241 said:

Looping cal 51

Found some information on the caliber 50. Basically looks like a really big watch you should Be able to a use a watch timing machine the regulated. Also the same rules would apply like a watch for how you set up the regulating pins the escapement etc.

https://calibercorner.com/looping-caliber-50/

You will have to use a translation program possibly depending upon your language skills and towards the bottom there is a picture of the parts list

https://forumamontres.forumactif.com/t39683-mouvement-looping-51-8-jours

Once I realized that there was a parts list available I found you some parts listings. One of the unfortunate problems of the existence of parts list is that conceivably there was servicing information. But typically we only get parts listing because that's all people care about.

 

1893_Looping 50, 51.pdf 3728_Looping 44,45,50,51,62,63,65.pdf 4380_Looping_ClockParts.pdf