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For you Rockford Fans

PatH

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Nice bit of Rockford history. Thanks for sharing it. It's likely obvious to watch or tool folks, but I have to wonder what it is called and what it's used for? Some sort of indexing? As always, many thanks for helping educate neophytes.
 

DeweyC

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Nice bit of Rockford history. Thanks for sharing it. It's likely obvious to watch or tool folks, but I have to wonder what it is called and what it's used for? Some sort of indexing? As always, many thanks for helping educate neophytes.
Pat,

I truly apologize, You are right, to me it is second nature. This is a factory made micrometer and was assigned tracking number of 868 for calibration purposes. The dial rotates so you can zero it with the pointer.

But the attention to finish is the story. The mechanism uses very heavy bridges (like a chronometer) and finely cut pinions and rack. If there is interest I will take it back apart and do pics
 

PatH

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Thank you, Dewey and Darrah!
 

musicguy

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As per a members suggestion I am moving this thread to the
Horological Tools thread


Rob
 
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DeweyC

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I'll save you the trouble Dewey. Here is an inside view of mine.
View attachment 721819
OK.This is NOT micrometer that measures metric or imperial. Went to use it and got very strange numbers. Checked with metric imperial feeler gauges and against other mikes. Did Rockford have their own system of units:???:??
 

Dr. Jon

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FRom its jaw shape it looks like it might be a mainspring thickness gauge and may be calibrated in mainspring strengths
 

DeweyC

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FRom its jaw shape it looks like it might be a mainspring thickness gauge and may be calibrated in mainspring strengths
Nope, not Mainspring gauge. It is a ratio scale (50 IS twos time 25) but I have no idea what the system of measurement. Nothing has been modified or replaced. The racks and pinions are not modified.

Curious.
 

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