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RP-24.3 Axles
| Scale | A Axle Diameter max | Y+ Shoulder min | U Axle Length max |
|---|---|---|---|
| O | |||
| S (see Note 5.) | .063 | 3/32 | 1.310 |
| On3 OO | |||
| HO | .063 | 3/32 | 1.035 |
| TT | |||
| HOn3 | |||
| N | 3/64 | 3/64 | .562 |
+ When used.
- NOTES:
- Shouldered axles may be used to insure proper wheel assembly. Enlarged center section may be contoured similar to the prototype.
- Dimension "U" for the Type I axle is taken at the theoretical point of the cone. A blunted point will measure shorter.
- Surface finish of bearing surface marked dimension "A" and coned surfaces should be smooth, true and free from irregularities.
- Cone point should be concentric with dimension "A" within 1/2% of "K" measured as TIR.
- For S scale: Axle insulating bushings are optional and if used may extend beyond the outer face of the wheel. The maximum allowable distance over the outer faces of bushings shall be 1.064 inches.