Flywheel, 3" Diameter, 6 Heavyweight Straight Spokes, Bronze

- Cast bronze flywheel
- Highest quality made by Martin Model & Pattern
- Fully Annealed
The flywheel casting is oversize so you can finish it to the specified diameter.
Photo shows the flywheel partly machined. This flywheel has a rim width of 0.779", a rim thickness of 0.285", a hub diameter of 0.715", and an overall hub length of 1.212".

All Martin Model & Pattern castings are fully annealed for easier machining.
When molten iron is poured into a sand mold, it cools very quickly where it contacts the cold sand. Quick cooling being the formula for hardening iron, this results in a very hard surface, or skin, on the casting. It's commonly known that you must address this hard skin when you start machining a casting.
But Martin Model castings go through another heat treat process. After the castings have cooled, they are once again heated to a high temperature, but this time they are cooled slowly. This ensures that the castings are evenly soft throughout, and that there is no hard skin on the surface
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