The Craftmans Shop > General Crafts

Regulator Clock

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smiffy:
Several years ago I started to build a regulator clock to a design by John  Wilding . This is along the lines of the  of clock George Graham used to check the going rate of clocks that he was repairing .
It is fitted with  maintaining work as designed by John Harrison . The idea of maintaining is to keep a steady pressure on the drive train during winding .
This is  achieved by there being 2 ratchets working in opposite directions inbetween the the winding drum and and drive wheel and the drive from the second ratchet is transmitted to the going train via a spring .
 In normal operation the spring is held under tension , as soon as you start to wind the clock the inner ratchet is locked by a pawl anchored between the frames and the drive to the clock is maintained by the spring ,the second ratchet can then allow the winding to commence with no loss of power to the drive train.
 The spring has enough energy stored to run the clock for about 1 minuet.

I never completed the clock as I was not happy with the escapement so today I made another one and cleaned the rest of the clock and fitted it
I forgot to take any pictures until I was getting ready to assemble it.
The clock is also fitted with stop work so it can not be over wound

The pallets I cut from 4 mm gauge plate filed to shape and finished the pallet faces on my Clarkson tool and cutter grinder .
Unlike a recoil escarpment which is fairly forgiving this is fitted with a dead beat escarpment which needs to be a lot more accurate

I hope everyone is coping with the present situation  I consider myself very fortunate as I have a large garden ,several workshops and no neighbors  and according to the better half I have been self isolating in one of my sheds for the last few years .

Sorry about some of the photos .the double image on some of them its reflection from the polished plates

Sea.dog:
A beautiful piece of work.

smiffy:
I tried to take some better pictures but found it impossible due to the reflection from the plates.
 
As i still need to do more polishing and cleaning I striped it down and took some more photos

The escarpment is fitted with adjusting screws to allow for final setting on to the pallets .One screw opens the pallets up and the other closes them up  . The pallet arbor is also fitted with eccentric bushes  .
 
Once set up is should be capable of keeping time to a few seconds a week
 
The second photo shows the spring that maintains the power during winding

smiffy:
I spent most of today finishing small parts such as 8 ba screws with over sized heads and blueing them
 
I blued them by heating in a bed of brass turnings . This gives a good controllable even heat . When the parts are a good colour I quench them in clean oil .

I made a brass screw driver so the screws do not get marked when fitting  also finished the winding handle and pulley for the going weight

 The 8 ba screws I fitted into a jig for slotting the heads   A bit overkill but I did them on my XYZ 1500  milling machine
 
Most of these parts I had started to make about 15 years ago so about time that I finished them  off

The 2 small screws in the  in the brass turnings are 10 ba and 8 ba   I have also used some 12 ba  to mount the wheels on the collets and for the 2 adjusting screws in the pallets .  No much fun tapping 12 ba 6 mm deep in gauge plate

I still have plenty more too do to finish it including making the case , 

 I will look at silvering the dial tomorrow but my silvering salts are a bit old and they might not be any good

smiffy:
I dont know how many people are interested in clocks but they fascinate me .  The type of regulator clock I am building was developed mainly but George Graham a student of Thomas Tompion and became a mentored to John Harrison who finally solved the problem of determining longitude while at sea.

George Graham worked in London as a clock  and instrument maker starting in the late 1600s. This regulator would have been used to check the accuracy of  other clocks.

The pendulum was mounted  on a stout iron frame and would have been fixed to a wall to in as much as possible isolate it from any undue vibrations that a clock mounted on a wooden floor might suffer from .
 
The clock was mounted on the same frame and the power to the pendulum is transmitted via 2 adjustable pins on the crutch
Usually the pendulum would be hung directly on the clock frames .
 
To save on friction there is no motion work as on normal clocks this allows second hour and minuet to all be mounted at the same place on the clock face .

On a regulator there are 3 separate dials  . The top dial is seconds the center shaft and longest hand is the minuets and the bottom dial records the hours .

Behind the dial the minuet hand is fitted with a counter balance  weight .

On most clocks the pendulum weight is supported on a nut which is used to lower or raise the pendulum to alter the time keeping
On this clock there is no rating nut . Instead there is a pin through the pendulum rod on this a brass tube rests and there is a pin through the pendulum that rests on the brass rod .

This is too compensate for expansion and contraction of the rod and pendulum . as the rod expands down the brass rod expands up and in theory equal each other out .

By the pendulum weight being supported in the middle it will expand  and contract equally  and not affect the going rate .

The rod length can be adjusted by placing shims on the brass rod or shortening it which ever may be the case.

For final adjustment there is a weight tray on the pendulum . Here small weight can be placed for final adjustment  .

A 6 ba nut will alter the rate by 1 or 2 seconds a week 

The weight is for testing when I have worked out how much it needs to drive it I will cast some lead in a brass tube

 In some of the photos I forgot to remove the winding handle

 I hope some one will find this of some interest

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