Winding Drum Sprocket
Circumference at top of teeth 1523
D-tooth top 484.786 Radius 242.393
Groove depth 6.85
D-groove bottom 471.086
D-chain roller 7.8
D-center of chain roller 478.886
Chain pitch:
Circumference of pitch circle 1504.465
Number of teeth 118
Chain pitch 12.7497
Access holes in sprocket:
D-access hole 100
Distance from tooth top(?) 64 <-- is this from top of teeth?
D-access hole center 128.393
Questions:
1. I have two measurements for sprocket thickness, 6 at teeth, and 16 at access holes. Where's the transition?
2. I got the sprocket tooth shape using information on sprocket-tooth layout on the web. Maybe these teeth aren't
so shaped.
3. I have answered 1. But there is a discrepancy. I have two dimensions on either side of disk, where the disk thickens just below
the teeth. On the outside: 1.87 , on the inside: 4 . With a disk thickness of: 6 , that gives
a thickness of the disk at the access holes of: 11.87 . But I measured: 16 . Where's the discrepancy?
4. What is OD and ID of thick hub at center of sprocket? ID should be shaft diameter.
5. Also, I don't think I have an end-to-end dimension on drum.
6. Or dia of drum.
Cable drum
Model grooves as circular arcs:
Number of grooves in sample 10
Distance btwn crrspndg pts 84.97
Single distance 8.497
Gap btwn grooves 1.45
Groove width 7.047 mm
Groove depth 1.85
Half width of groove (b) 3.5235 Page 6 of Owen notebook
phi 62.29846
theta (groove arc angle) 55.40309
r 4.28042 mm
Circumference to top of lands 1422
D-top 452.6367
R-top 226.3183
R-bttm 224.4683
R-center of arc 228.7487
Ctr above blank 2.43042
Drum length 298
No. grooves 35.0712