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Clock Project

pilotingpete

Registered User
Oct 18, 2014
8
0
1
Hello All,

I've been contemplating designing/building a clock movement for some time now. And despite a fair amount of reading, I must admit I don't have all the answers.

Thus far I have been able to work up the attached spreadsheet for the going train. When working out the ratios I wanted to keep with a single module, and common pinion leaf number to keep cutter cost down. I believe I will end up needing a cock for the intermediate wheel due to its neighbours diameters.

I am wondering if anyone has feedback on the selected ratios shown?

Also, when manufacturing a clock from scratch, and with known module cutters, would one still use a depthing tool for layout or would you place the bushing at the theoretical ideal location instead.

Thanks

Screen Shot 2019-02-18 at 4.17.16 PM.png
 

John MacArthur

Registered User
NAWCC Member
Feb 13, 2007
365
34
28
laplaza.org
Pete - you would definitely do best with a depthing tool. Once I get the wheel/pinion pair depthed correctly, I measure the inside and outside arbor distances, and divide by two. Then you know the exact center distance. This is called "field verify all dimensions" on blueprints and such. I then draw circles in CAD of each distance, and the intersection of the two circles for each pinion/wheel pair will give you coordinates, which you can then drill. This will usually vary somewhat from the theoretical. I assume you have a DRO on your mill, or you wouldn't have mentioned "theoretical ideal location". Good luck, and keep us posted. BTW, the answers don't all come from reading books, they come from trial and error. I have bushels of mistakes.
Johnny
 
Last edited:

pilotingpete

Registered User
Oct 18, 2014
8
0
1
Pete - you would definitely do best with a depthing tool. Once I get the wheel/pinion pair depthed correctly, I measure the inside and outside arbor distances, and divide by two. Then you know the exact center distance. This is called "field verify all dimensions" on blueprints and such. I then draw circles in CAD of each distance, and the intersection of the two circles for each pinion/wheel pair will give you coordinates, which you can then drill. This will usually vary somewhat from the theoretical. I assume you have a DRO on your mill, or you wouldn't have mentioned "theoretical ideal location". Good luck, and keep us posted. BTW, the answers don't all come from reading books, they come from trial and error. I have bushels of mistakes.
Johnny
Thanks, Johnny. That is an interesting idea to use the depthing tool in that manner - I hadn't considered that.
 

Hessel Oosten

Registered User
Apr 26, 2017
33
4
8
The Netherlands
Country
Hi Johnny,

I'm so sorry, but I did not understand the procedure.
The depthing is clear of course.
This procedure gives -one- right distance between the 2 centers (of course).

But then your sentence...: "I then draw circles in CAD of each distance".
I don't understand what "each distance" is here. We measured ONE distance before.

Or... may be, do you have a small picture, probably the best way for explanation this seemingly simple problem ?

Thanks,

Hessel
 
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