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Servicing a Hammond Bichronous Movement

Allan Wolff

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Mar 17, 2005
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This is my first time servicing a Hammond Bichronous electric movement. As I have found in previous threads, this one has the usual teeth missing from the fiber start wheel and the power cord is bad. It is also severely gummed up from dirt and dried oil. The backup power mainspring is very sticky and I would like to clean and re-lube it. Does anyone know how to get at the mainspring on these movements? The brass cap is attached inside somehow and both ends of the gear assembly appear to be pressed onto the shaft.
Thanks,
Allan

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Tim Orr

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Sep 27, 2008
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Good evening, Allan!

Ken Reindel of kensclockclinic.com is an expert on restoring these clocks. You might want to visit his website and contact him. He recently did a presentation for Chapter 21 in Denver (on Zoom) regarding these clocks, and it was recorded.

Best regards!

Tim Orr
 

Tim Orr

National Membership Chair
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Sep 27, 2008
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Good evening, Allan!

Here's the video recording of Ken's presentation:

Best regards!

Tim
 
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Allan Wolff

Moderator
NAWCC Member
Mar 17, 2005
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Tulsa, OK
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Tim,
Thank you very much for providing the link to the video. It contains a lot of useful information on repairing one of these movements. I've got it book marked along with Ken's presentation on overhauling electric clock motors. Please pass along my thanks to Ken for putting this excellent presentation together.

There was not a lot of information on accessing the mainspring, but Ken's advice on levering the cover off with a sharp screw driver pointed me in the right direction. I finally got the cover off. As you can see, the old dried oil around the rim made an effective glue. I've got a few pry marks on the cover to clean up.
Thanks again,
Allan

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