English Lever pocket watch problem

[MrWatch]

I am working on this English Lever pocket watch. While disassembling the watch, I noticed that at the lever a small brass pin is missing. (see picture below)
I don't know what function this pin has. Maybe it's for limiting...

Does anyone have an idea how to make a new pin?

I already tried to file a brass pin to the appropriate thickness. I can't get it, that the pin has a firm hold in the pin hole. 

It would be great if someone could help me.

Jens

[Nucejoe]

It is called guard pin, has no function, it's job is to go through the hollow in the roller, so to insure the impulse jewel is at right angulare position to receive energy( push) from the fork. If balance wheel picks up speed say by a sudden move of wrist the guard pin will hit the roller.

Google brings up host of articles on the subject, I never heard making such a pin, though similar looking pins were produced and possibly of use for guard pin.

 More response coming in will be of help to you.

[MrWatch]

Thank you for your help Nucejoe. What do you think, would the watch work without this guard pin?

[HSL]

Lets us say that the guard pin does not have any function in the time keeping. But I think it is an essential part if you want to wear your watch since it has a similar function as the incablock shock springs.
It's main function is as the name implies to make sure the horn isn't reaching the impulse pin and breaking it of or get jammed in any way.
If you look at a pallet fork under high magnification you can see that the guard pins distance to the roller where the impulse pin is seated is slightly shorter than the pallet horns.
This assures a safe operation if a shock is distributed to the watch, the smaller distance to the roller makes the guard pin hit the roller first.
Side shake can't be avoided since you want your pinions to run clear in the jewels, it is this side shake the guard pin protects against.
If you are making a guard pin you have to keep this in mind, the pin has to be slightly longer than the pallet horns but still have enough clearance to the roller to ensure normal function.
So i guess the answer to your question is , Yes the watch will work without the guard pin, but you might only use it in a static position otherwise it will stop now and then or stop permanently.

[MrWatch]

Thank you for your detailed explanation HSL! Now I know what function the protection pin has and that it's an important part of the lever.

Does anyone have an idea how to make a new pin? Do I need a special conical pin? Are those pins commercially available?

I already tried to file a brass pin to the appropriate thickness. I can't get it, that the pin has a firm hold in the pin hole. 

 

[Nucejoe]

Will run, but as HSL stated good for static position, on wrist however as I put it, by shake of hand balance wheel,s angular velocity can alter and get thrown out of design beat, that is ; not be at right position at the right time, so it misses energy reception in that beat, for next beat, if the wheel got enough speed/energy to release entery or exit pallet from escape, by the time the impulse jewel is timely  back in position to receive energy , it will receive energy, recovers and goes on, business as usual, if not it will stop. 

Regular  designs give one push to impulse jewel in two beats, Co-axial escape ( the smart design of the british designer) imparts one push in each beat so is less likely to stop without guard pin.

( I have loosely used the term angular speed for angular velocity.)

To make a long story short, you need a guard pin,.make sure the impulse jewel runs freely over the pin, not rub on the pin when runing through the horns.

 

[jdrichard]

I would make one out of steel or brass in a lathe and then perhaps shellac it in place

Sent from my GT-N5110 using Tapatalk

[MrWatch]

Hello jdrichard, thank you for your advice. There is my problem, unfortunately I have no lathe.

[rodabod]

You could buy some tapered pin and then use this. 

[StuartBaker104]

If you don’t have a lathe then you could improvise... an electric drill will suffice for a task like this. If the chuck is too large to hold the stock then hold a pin vice in the chuck. You can use a fine file or emery stone to remove material and just hold it gently againt the pin and move back and forth.

The end of the pin should be filed to a flat point, and set the length as described below

 

[MrWatch]

Hello everybody,

thank you all for your helpful advice.

Meanwhile I ordered a few brass pins. In the basement I found an electric drill (Dremel), which I have hardly used.

So I will try to make a new guard pin. I will keep you up to date and hope I will succeed. I'll do my best ...

Jens

 

[StuartBaker104]

Coincidentally I’ve been working on an English lever carriage clock platform with a solid guard today. Sadly the guard is worn to the point that sometimes the roller actually draws the lever round before the impulse jewel enters the horns.

The platform is silvered and otherwise rather nice, so I'd like to repair it.

The lever and pallet are two separate parts, and Gazeley says that the solution here is a new lever but I’m not sure I’m up for making a new lever (although it looks as though someone may have done previously). I think my best option here will be to file back the guard and drill a hole (perpendicular to the lever) to fit a brass pin.