You are a tool and die maker for a fabrication shop. A big part of your job involves operating the machinery needed to create metal tools and forms.

Today you're making a tool out of low-carbon steel. Your next step for this tool is the drilling machines -- you want to make a number of smooth cuts through the steel.

Since each surface reacts differently to a tool, you will need to find out how quickly the tool will move through the steel. To get the smooth finished surface you need, you'll need a drill that cuts at least 600 revolutions per minute. Anything slower would make for a rough surface.

You know low-carbon steel has a cutting speed of 80 feet per minute. Using the cutting speed formula listed below, figure out what the revolutions per minute will be for a one-half inch drill on this surface. Is this quick enough for your needs?

The simplified formula for figuring out revolutions per minute (RPM) is:

RPM = cutting speed (feet per minute) x 4 / diameter of cutter

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