..Alright everyone bear with me here... I'm trying to get into the "nitty gritty" of polishing, sure I can make stuff shiny BUT!....I'm confused about the whole SFPM thing....

Caswell's manual shows a formula of (1/4 dia. of wheel X Motor RPM) =SFPM, and for best results use a SFPM speed of 3600-7500.....Here's where the confusion comes in: If you use a 6" wheel on a 3000 RPM motor, you're turning 4000 SFPM...if you use an 8" wheel on the same speed motor, you're turning 6000 SFPM. How can you have a higher Surface speed, if having a larger diameter wheel theoretically is turning slower than a smaller diameter wheel running with the same SPINDLE speed

Caswell's manual shows a formula of (1/4 dia. of wheel X Motor RPM) =SFPM, and for best results use a SFPM speed of 3600-7500.....Here's where the confusion comes in: If you use a 6" wheel on a 3000 RPM motor, you're turning 4000 SFPM...if you use an 8" wheel on the same speed motor, you're turning 6000 SFPM. How can you have a higher Surface speed, if having a larger diameter wheel theoretically is turning slower than a smaller diameter wheel running with the same SPINDLE speed

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