grit question

[FrankenPC]

Is there a breakdown somewhere of the effects of grit on various metals? For instance, 600 grit aluminum oxide sandpaper against hardened steel at X feet/minute with Y pressure in lbs/inch of grinding will yield a net loss of .001 inches/minute. Or equivalent type chart.

Probably sounds like a silly question. But I would like to know generally what I'm getting myself into before I begin a sanding/grinding process.

Thanks for any info!

 

[Tony Wells]

And if you get rough with it, and it's critical, you'll have to cool it back to room temperature to measure.

I've not seen anything like a chart either. It's probably better to cut close to size, and only polish for required finish. If you can't hit the size, you may have to polish it in, or get rid of some taper. In any case, a little practice, or machine maintenance would be good.

 

[FrankenPC]

Good question, FrankenPC. I've not seen such a chart, but I will say it takes a long time to sand of a couple thou off an oversized part with fine paper. If you sand just until it's shiny, you'll take off mostly high spots. I get best results if I wet it with some kerosene or WD-40, and keep the sandpaper moving back and forth constantly. I use emery cloth, then wet/dry 500 or 600. If the OD is critical, you might practice on some scrap, but I think you'll find you do more stopping and measuring than you do removal of OD.

Thanks for the reply.

Does Kerosene cause any problems with Granite surface plates?

 

[Tony Wells]

No damage, but it will leave a little oily film on it that will attract dust. I usually clean mine and just leave it dry, and gather little dust that blows/wipes right off. I know people that use GoJo on their plate, and like the shine. I like clean and dry.