these gears have TAPERED center holes; approximately:
1 7/16" - 1 11/16"

about 1" thick

as an example the 47t was about 6 1/8" OD, the 53t about 6 7/8".

tnx,
barry
carson city nv




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Barry Tuttleman
Carson City, Nevada
websites:
industrial/manuals/slots/aircraft:
http://home.att.net/~btuttleman/barrysite.html
electronics:
http://home.att.net/~btuttleman2/electron.html