Clockmakers Aid

Historical Clock and Watch Research
Find the details of the maker of your clock or watch here!
www.clockswatches.com

Clockmakers Aid V3.0

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Copyright T Harrsion-Smith 2000

This page may be distirbuted freely, at NO-COST to the recipient, and it may not be amended in any way without prior permission form the author who may be contacted at clockaid@pattens.co.uk  

The original 'Clockmakers Aid'  was published as a DOS program in 1988 and was intended to provide a quick and easy access to the calculations that you only need occasionally but when you need them you need them right away without the hassel of searchin your library for them. This lated version has been written as an HTML page with no additional graphics so that it can be saved on your desktop and called whenever it is needed. I hope you find this version as useful as the original 2 versions.

To keep this page self contained the normal link buttons  have been omited. To go to the web site, click the link below

These pages have been tested on Microsoft's internet  Explorer V4.01 and Netscapes Navigator 4.0

Timekeeping

Pendulum details from a known gear train
Change in Pendulum Length to correct inaccurate timekeeping
Theoretical beats per hour for a pendulum length stamped on a clock

Wheel cutting

Wheel blank diameter and depth of cut
Wheel module
Cutting speed

Mainsprings

The amount to shorten an overlength mainspring

General

Show approximate current moon phase

Note: Gravity to be used in these calculations is cm/sec/sec Click here for alternative gravity values

Calculate Pendulum Details
(3 or 4 wheel train)

To check the timing of a clock or watch, you need to know the beats per hour. This page will allow you to enter the wheel counts and then it will show the beats per hour. There is no error checking, so make sure you enter the correct figures.

For a 3-wheel train, leave the FW and FP values at 1.

Enter counts for:-
Centre wheel teeth (CW)
Third wheel teeth (TW)   pinion (TP)
Fourth wheel teeth (FW) pinion (FP)(* See Note)
(* If you don't have a 4th wheel in your clock train leave the values as 1)
Escape wheel teeth (EW) pinion (EP)

Results

Back to menu   View Manual


Calculate Change in Pendulum Length to correct inaccurate timekeeping

Use this option after you have run the timepiece for a test period and noted the timekeeping error over that test period.

Duration of test period (ie. 36.5 hours) Hours
Error found during test Minutes      Lost Gained
Beats per minute or time of pendulum swing in seconds
Results

Back to menu  View Manual


Calculate theoretical beats per hour for a pendulum length stamped on a clock plate

On some clocks there is a theoretical pendulum length stamped on the back plate. With French clocks, the unit of measurement is Pouces with the whole number being to the left of the pendulum and the decimal to the right. On the more modern European clocks the theoretical pendulum length is given in cm. Thes figures can help in the setting up the rate of the clock.

Enter the unit of measurement Pouce cm
Enter the length stamped on the back plate
Results

Back to menu  View Manual


Calculate wheel blank diameter and depth of cut

These calculations will help prepare the blank and cutting machinery for manufacturing a new wheel or pinion. The correct depth is best found visually, adjusting the cutter in until the correct tooth shape is formed.

Module Required
Number of Teeth   

Results

Back to menu View Manual


Calculate a wheels module

This option will help you find the correct cutter to make a replacement wheel or repair an existing wheel. The correct depth is best found visually, adjusting the cutter in until the correct tooth shape is formed.

Wheel Diametermm
Number of Teeth   

Results

Back to menu View Manual


Calculate correct cutting speed

Find the suggested optimum rpm for machining metals. The rpm's are based on the assumption that sharp High Speed Steel tools are used. If you are drilling, I would suggest that you reduce the suggested speed by about 20%.

Diameter of work or cuttermm
Material   

Results

Back to menu  View Manual


Calculate Change in Mainspring Length

In the UK, mainsprings are bought by specifying the barrel diameter, thickness and width. Sometimes to get the correct thickness, a larger barrel size will need to be ordered. The spring supplied will then be too long. This page will calculate the approximate length that needs to be removed from the mainspring supplied.

Calculate amount of spring to be removed.
Enter supplied Barrel Diameter: mm
Mainspring thickness: mm

Enter the actual Barrel Diameter  

The amount of spring to be removed is mm

Back to menu View Manual


Show current Approximate Moon Phase

Within 2 days, today is day in the moons cycle. The next new moon will be in approximately  days time.

Back to menu  View Manual

 

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