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1.6 Do Machinists Do Math?

D.M. Donner

Students frequently ask if they have to do math. There seems to be a general reluctance to perform basic math (Aguilar, 2021). It could be due to a negative experience in high school when math classes seemed to have no relevant purpose. Re-learning basic math skills during your training will help you solve real-world problems, making math seem more relevant than it did previously.

This question about doing math is a two-part question; do I have to take math during my training? And do machinists have to do complicated math in the industry? The answer is Yes, and No. Yes, you will need to take a math class during your training at a community or technical college. These math classes are usually “math for the trades” or something similar where you perform functions like measuring the area of a piece of sheet metal or calculating the volume of a cylinder. Addition, subtraction, multiplication, and division are the principal skills necessary for an entry level machinist.

A CNC bed mill has a vise bolted to the worktable with a 3 by 6-inch piece of aluminum secured in its jaws. An engraving tool contacts the stock surface and engraves letters onto the surface of the metal.
Figure 1.11. A machinist used addition to calculate the size of the font necessary to fill the piece of aluminum. / Image Credit: Damon Donner, CC BY 4.0

Machinists perform math to determine whether their parts are within tolerance and to calculate how much to compensate a tool to achieve the desired dimension. These tasks require the ability to add, subtract, multiply, and divide. If you need to calculate how much further to compensate an 82° spot drill to achieve the desired diameter chamfer, you can use a trigonometric calculator.

It is this author’s opinion that you use the tools at hand. Gone are the days of slide rules and trigonometry tables. The calculator on your phone, a website, or, better yet, a simple free app downloaded on your phone can provide all the math assistance you need until you are comfortable performing these basic functions yourself.

Attributions

  1. Figure 1.11: A CNC bed mill by Damon Donner, for WA Open ProfTech, © SBCTC, CC BY 4.0

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Introduction to Machining Copyright © by SBCTC is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.