NOTES FROM THE BENCH
Clock Repair Archive - - Seth Thomas 115d:
The Seth Thomas 115d is a ships strike round mechanism. It uses a non - imported balance
wheel unit. It uses a cam on the idler gear connected to the minute wheel to make the odd
count ; it lifts the lever that catches the hammer causing the "odd" count on the half hour.
The rack uses a counter weight with a
return spring to facilitate it's operation. The return spring on the rack is .010 inches in
diameter. The rack has a spring loaded index end that will release if the mechanism is
allowed to run down , in case the hands are moved before the rack has cleared the snail.
The spring for this is .021 inches in diameter (brass). The strike trip lever return spring is
.013 in. diameter brass wire with a .010 wire inside the plate also. The hammer return
spring is .016 in. diameter brass wire. Be sure there is at least 180 degrees of rotation on
the warning wheel after the warning pin is caught (when the mechanism "loads" the strike gear train
prior to releae) before the hammer is picked up
or the odd hour strikes will be erratic because the hammer catch won't always hook.
Back to Notes From The Bench index
Page by: Perpetual PC's
Copyright (c) 2002 David Tarsi.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1
or any later version published by the Free Software Foundation;
with the Invariant Sections being no invariant sections, with the
Front-Cover Texts being no Front-Cover Texts, and with the Back-Cover Texts being
no Back-Cover Texts.
A copy of the license is included in the section entitled "GNU
Free Documentation License".
The content of this website and journal
has been prepared to provide information on the authors experience.
The information is not a complete source.
Use at your own risk. Any advice given by the author also is covered by this
statement. This website and journal is not endorsed by any manufacturers mentioned.
This website and journal has no connection whatsoever to any of the manufacturers mentioned.
Your use of this information and your use of any advice given by the author
is your acceptance of responsibility for all consequenses resulting in such use.
No legal liability attaches to the author, the website, or the isp for any inaccurate
or misleading information contained on the website and journal at any time or for the consequences
of any errors or omissions or for the use of said information. However if written
notice is given to the webmaster of inaccuracies or omissions, the author will endeavor
to establish the factual position and where necessary correct
the content of the website and journal in an appropriate and timely manner.