Student Activity Student Activity RPM 12 x CS \u03c0 x \u00d8RPM 12 x 720 \u03c0 x 0125 RPM

Student activity student activity rpm 12 x cs π x

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Student Activity
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Student Activity RPM = 12 x CS π x Ø RPM = 12 x 720 π x 0.125 RPM = 22,002 You need to cut aluminum on a mill with a coated carbide cutting tool. The diameter of the cutter is 0.125 inches. What is the correct, calculated RPM? Hey, 22,002 RPM is way to fast for most machines and setups! When the numbers seem high (for example, over 400 RPM for students), ask your shop professor if it is safe to run the machine at such high RPMs!
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You need to cut 4140 alloy steel on a mill with an uncoated carbide cutting tool. The hardness of your steel is 250 Brinell. The diameter of the cutter is 0.75 inches. Using the average cutting speed from the speed & feed tables in your Machinery’s Handbook, what is the correct, calculated RPM? Student Activity
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You need to cut 4140 alloy steel on a mill with an uncoated carbide cutting tool. The hardness of your steel is 250 Brinell. The diameter of the cutter is 0.75 inches. Using the average cutting speed from the speed & feed tables in your Machinery’s Handbook, what is the correct, calculated RPM? Student Activity RPM = 12 x CS π x Ø RPM = 12 x 25 π x 0.75 RPM = 127
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Since 12/ π is equal to approximately 4, the following formula can also be used for quick, rough calculations in the shop: RPM – Simplified Formula RPM = 4 x CS Ø
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In practice, there are several other factors that can affect cutting speeds: Condition and heat treated state of the workpiece material. Use of coolant, how it is mixed and how it is applied. Type and grade of tooling material. Operation being performed. Feed rate and depth of cut. Condition of machine and workpiece clamping. Desired tool life. RPM – Other Considerations
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It is common for highly experienced trades people to set speeds by eye. Students at Seneca College must always perform the calculations. You may be tested in this area both at the College and by the Ontario Government on the Certificate of Qualification Examination. RPM – Other Considerations
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The feed rate is the linear speed at which the cutting tool is traversed over the workpiece. It is sometimes referred to as, “table feed.” Although feed rates can be found in the Machinery’s Handbook, they are normally set in order to achieve a desired surface finish. High feed rates = Rough surface finishes Low feed rates = Fine surface finishes Experienced machinists and engineers will often set feed rates without calculating them, based on years of work experience. Feed Rates
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In order to calculate feed rates for a milling operation, the following information must be determined beforehand: 1. The RPM 2. The number of cutting teeth on the cutter 3. The depth of cut per tooth in ipr (inches per revolution).
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  • Summer '20
  • Milling machine, Lathe, Milling cutter, carbide cutting tools, HSS Cutting Tools

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