17 Handy Calculators and Reference Charts for CNC Machinists [ Free! ]

cnc machinist calculator charts reference tables

Do you refer to Machinery’s Handbook a lot for the quick reference charts? Do you use online Calculators of various kinds to figure out your machining problems?

I used to, but then I got tired of leafing through thick handbooks and trying to find things on the web at the last minute. Yes, they’re great resources, but I wanted things to be a lot closer to my fingertips. I wanted a higher concentration of useful tools.

To make that happen, I started building what would eventually become this page. I hope you get as much use out of all these free resources as I have. One thing you’ll notice is most of the free calculators are built right into our G-Wizard software. That’s no accident, but you’re probably wondering how something built into a piece of paid software can be free? I’m glad you asked!

If you do the G-Wizard free 30-day trial, when it ends, you’ll still have access to all the free calculators. The only thing you lose if you choose not to buy at the end of the trial are the Feeds and Speeds-related functions. That still leaves a huge amount of territory–useful time saving tools that are listed below.

Bolt Circle Calculator

Bolt Circle Calculator: Generate the coordinates for a bolt circle quickly and easily with this handy free calculator.

Feeds and Speeds
Calculator

CNC Feeds and Speeds Calculator: Get the industry-leading Feeds and Speeds Calculator used by thousands of the best manufacturers in the world and improve your tool life, cycle times, and surface finish today.

Machine Hourly Rate Calculator

CNC Machine Hourly Rate Calculator: Figure out what hourly rate to charge for your CNC machines.

Drill Bit Tap and Size Chart and Calculator

Drill Bit Tap and Size Chart and Calculator: A full drill index, recommended tap drill sizes, thread percentages vs strength, free calculator, and more!

Feed Rate Calculator

Feed Rate Calculator: A quick free calculator for feed rates when milling.

G-Code and M-Code Reference

GCode and MCode Reference: Need a handy reference chart for all the GCodes?. Look no further. There are charts for Milling GCodes and Turning GCodes. And, there are Tutorials and Sample data from our Free GCode Tutorial too!

GD&T Symbols Chart and Calculator

GD&T Symbols: Geometric Dimensioning and Tolerancing Symbols in a convenient chart with tutorial information on the symbols from our Free GD&T Course too!

G-Wizard also has a GD&T symbol chart with links to tutorials and a True Position Calculator.

Hardness Conversion Charts

Hardness Conversion Charts: Hardness Conversion Charts, Free Calculator, and information for Rockwell, Vickers, Brinell, Shore Scleroscope, and more Hardness Scales.

Lumber Sizes

Lumber Sizes: Ever notice a 2 x 4 doesn’t measure 2 by 4 inches? Here’s the scoop on the actual sizes for lumber, despite what we call it. There’s even a free calculator for weights and volumes based on the actual sizes.

Polar to Rectangular Calculator

Polar Coordinates Calculator: Convert from Polar to Rectangular (Cartesian) Coordinates easily.

Sheet Metal Wire Gauge Sizes

Sheet Metal Wire Gauge Sizes Chart / Table and Calculator: Sheet metal gauging is somewhat arbitrary, but we’ve got full reference charts plus a nifty free calculator to help right here.

Steel I-Beam, Channel, and Angle Sizes

Steel I-Beam, Channel, and Angle Sizes: Complete Guide to Standard Sizes for Steel I-Beams, HSS, Channel, and Angle.

Surface Finish Chart Tables

Surface Finish Chart Tables: Complete Guide to Surface Finish Charts, RA, RZ, Measurements, Callouts and Symbols.

Tap Speeds and Feeds Calculator

Tap Speeds and Feeds Calculator: Quick Calculator for tapping feeds and speeds.

UN & ISO
Thread Calculator

G-Wizard’s built-in Thread Calculator is loaded with features and information, and it’s completely free. Just sign up for the 30-day trial and the Thread Calculator is yours forever.

Vacuum Table Pop-Off Calculator

Vacuum Table Pop-Off Calculator: Quit scrapping parts because they pop off your vacuum table.

Drill Feeds and Speeds Calculator

Drill Feeds and Speeds Calculator: A quick free calculator for drilling feeds and speeds. Plus an advanced industry-leading feeds and speeds calculator for more serious work.

Fits and Tolerances Calculator

A quick Free ISO Tolerances Calculator based on ISO 286, ANSI B4.2, and DIN 7172.

Drill Bit Size Chart

drill chart bit sizes

Drill Bit Size Chart: A quick free drill bit size chart, downloadable pdf, and drill size calculator for more serious work.

Metal Weight Calculator

Metal Weight Calculator: Calculate volume and weight for a variety of materials and metals with our free calculator.

Yup, it’s true, you got this far and didn’t find the information you were looking for. Happens to the best of us. When all else fails, I always turn to Machinery’s Handbook to look for information.

One more sneaky trick: buy one or two editions back–not the latest. Most of the info hardly changes and you’ll save a bundle!

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