{"id":3614,"date":"2025-03-07T17:42:54","date_gmt":"2025-03-07T17:42:54","guid":{"rendered":"https:\/\/www.slbbhi.co.uk\/?page_id=3614"},"modified":"2025-03-13T18:02:29","modified_gmt":"2025-03-13T18:02:29","slug":"pendulum-length-calculations","status":"publish","type":"page","link":"https:\/\/www.slbbhi.co.uk\/?page_id=3614","title":{"rendered":"Pendulum Length Calculations"},"content":{"rendered":"\n

TO CALCULATE THE WHEEL COUNT AND FIND THE EFFECTIVE LENGTH OF A PENDULUM<\/u><\/strong><\/p>\n\n\n\n

A spreadsheet to perform the calculations below is available. To download the spreadsheet click Pendulum Spreadsheet <\/a>
<\/p>\n\n\n\n

If you find the beat for a clock without a pendulum it is possible to calculate its length by proportion to a second\u2019s pendulum which is 39.14 inches.<\/p>\n\n\n\n

To do this follow the steps below.<\/p>\n\n\n\n

Count the number of teeth on Centre, Third and Escape wheels. Count the number of teeth on Third wheel and Escape wheel pinions. Put the figures into the formula below.<\/p>\n\n\n\n

 <\/strong>Z<\/strong> =    3600 X Number of pinion leaves in third X escape       <\/u><\/strong>
\n         <\/strong>Number of teeth in centre wheel X third X escape X 2<\/strong><\/p>\n\n\n\n

Note<\/u><\/strong><\/p>\n\n\n\n

The multiplier 2 is because there are two pallets on the escapement.<\/p>\n\n\n\n

3600 is the number of beats in an hour for a second\u2019s pendulum which is 39.14<\/strong> inches long.<\/p>\n\n\n\n

Effective Length = Z2<\/sup> X 39.14 inches, <\/strong>to get millimetres multiply by 25.4<\/strong>.<\/p>\n\n\n\n

Note<\/u><\/strong><\/p>\n\n\n\n

The effective length is from the bend of the suspension to one third down the pendulum bob. The rest of the length is assessed by adding 2\/3 diameter of the bob and the rating nut plus the threaded length.<\/p>\n\n\n\n

Here is a worked example<\/u><\/strong><\/p>\n\n\n\n

  <\/u><\/strong>3600 X 8 X 8<\/u><\/strong>       = 0.5<\/strong>\n
96 X 80 X 30 X 2<\/strong><\/p>\n\n\n\n

39.14 X 0.5 X 0.5 = 9.785 inches<\/strong><\/p>\n\n\n\n

       <\/strong>9.785 X 25.4 = 248.5mm<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

TO CALCULATE THE WHEEL COUNT AND FIND THE EFFECTIVE LENGTH OF A PENDULUM A spreadsheet to perform the calculations below is available. To download the spreadsheet click Pendulum Spreadsheet If … <\/p>\n

Continue reading “Pendulum Length Calculations”<\/span><\/a><\/p>\n","protected":false},"author":14,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-3614","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.slbbhi.co.uk\/index.php?rest_route=\/wp\/v2\/pages\/3614","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.slbbhi.co.uk\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.slbbhi.co.uk\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.slbbhi.co.uk\/index.php?rest_route=\/wp\/v2\/users\/14"}],"replies":[{"embeddable":true,"href":"https:\/\/www.slbbhi.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3614"}],"version-history":[{"count":6,"href":"https:\/\/www.slbbhi.co.uk\/index.php?rest_route=\/wp\/v2\/pages\/3614\/revisions"}],"predecessor-version":[{"id":3624,"href":"https:\/\/www.slbbhi.co.uk\/index.php?rest_route=\/wp\/v2\/pages\/3614\/revisions\/3624"}],"wp:attachment":[{"href":"https:\/\/www.slbbhi.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3614"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}