Hi Brett,
This ('scape) wheel was cut from silver steel using a single point fly cutter similar to Russell's setup.
The cutter was (also) silver steel, hardened and tempered. With a dividing head in a mill/drill, I cut the teeth in two distinct passes to get the angles right. In other words, the cutter was not full-form. You can get an idea of this from the roughness at the bottom of the teeth.
Initially, this profile was cut a short distance along the bar of silver steel before parting off. Subsequently, the wheel was itself hardened and tempered
The diameter of the wheel overall is 3/4" (19mm) and the eventual thickness 1/16" (1.5mm)

Hope this adds more confidence re cutting the teeth in steel.
Regards,
Sam