Dial Repairs


Repairing dials

Many dials become sluggish after a while, usually through dust and/or over-lubrication in the past. If you are lucky they will respond to a very small drop of light oil on the insides of the governor cup and on the governor worm drive.  DO NOT use WD40.   If this fails then you will have to do a full disassembly job (tedious!), followed by washing in white spirit.  Afterwards lubricate the re-assembled item with a minute amount of watch oil.  Maplin and other electronics component shops sell a micro-spout oiler containing oil and Teflon particles for a very moderate price.

If the problem is a broken spring, this advice from Steve Hilz will help. “You can rewind dial springs by carefully pushing the mainspring into the holder and working it into the centre as you go.  You have to watch out that you don't let the spring release, but it will go back OK with some patience.  Wear gloves so you don't cut yourself.   If you have a broken spring near the end, you can anneal it in a flame and let it cool gradually.  Then, make the bend that you want to be permanent.  Then, reheat the portion of spring that you annealed, until it is red, then quench it in cold water to restore the temper.”

Usual dial failures are:-

  1. Noise - Lubricate governor cup - a drop of light oil on the end of a small screwdriver.

  2. Slowness - Check for dirt and fluff on the gearing.  Remove and just dab a minute drop of oil on the governor spindle.

  3. Slowness - Lubricate governor cup and dial central spindle.  Central spindle can become packed with oil residue - complete strip down to cure this.  On reassembly use a very small amount of oil on the central spindle.

  4. Dial not returning - Firstly check for fluff and dirt.  Then check the spindle to see if seized.  To do this remove the governor and clutch.  If the central spindle still will not rotate or rotating very slowly then the dial is seized or the return spring is broken - complete strip down. 

  5. Dial not returning but spindle rotates - probably a broken dial spring  - complete strip down and replace the spring.

Tips:-

  1. Dial speed - dial the digit 0 and on it's return say "one - one thousand and one" at normal speech speed.

  2. Broken dial spring - generally all GPO dial springs from the Dials No's 10 to 30 will work in any dial.

  3. Do not dowse in oil.  A drop on the tip of a very small screwdriver is more than enough.  Oil tends to go sticky with age and gunge up!

Dial 10 - 11 adjustment Document

Dial 12 - 30 adjustment Document

 
 
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Last revised: July 13, 2020

FM2