Fractional and metric to decimal inch chart

Let’s try this again. Here is a handy sheet when you need to quickly convert fractional or metric values to decimal inch.

DecimalChart.pdf (200.1 KB)


Someone else just posted one they made with the cnc but I can’t find the post for the life of me. Really liked that version so would love to make one similar as I found it was very easy to read and not too busy. If anyone saw that post can you send it to me? Roughly 3 more weeks before my Woodworker is received. Thanks in advance!

I made a chart. I thought I had posted it here… But must have only posted on the FB page. I really like the Amana 45772-K 30 degree engraving bit. It does a fantastic job.

CNC Information board – digital copy – Silentmars Workshop


One other thing I found is that white oak is the best for the doing very detailed work without it being a pain to clean up.


Thanks Frank! I like that your design has more than just the measurement conversions.

Hey @FrankP, I didn’t check all of the fraction/decimal/metric conversions but I do notice that it looks like you may have accidentally converted 1/64 into CM instead of MM.

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Good catch!
As a retired machinist I just do it the old fashioned way
MM/25.4=inch or inchX25.4=mm. Always have a calculator handy. Although after doing it for 40+ years, most common sizes are in my memory. One bit of trivia, to calculate drill size for metric taps, Diameter-pitch= drill size. Example for M5X.7 tap, 5-.7=4.3, drill size=4.3mm

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Looks like I was copying the wrong part of the chart I found online the first two where wrong. I have updated it now, Thanks.

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Machinist here too but I learned differently.
Inch to metric… inch divided by .03937 = metric value.
Or, mm times .03937 = inch value.

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Too Cool! Keep’em comin’ :+1:

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Both ways work, but 25.4 is exact where as .03937 is actually rounded from 0.03937007874015748031496062992126
Not that it matters unless you are working on atoms:)

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Hey Frank, do you have the actual file so we can print larger, crisper copy?


I have the file available on my site if you click the link above. :slightly_smiling_face:

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Thank you very much Frank.
Idaho Falls, Idaho

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You could try this one. I made this up in Carbide Create.

CNC Useful Info

I am cutting it right now to see how it comes out.

CNC Useful Info.pdf (1.6 MB)

Here is a PDF of my “Cheat Sheet” I’ve made for anyone who is interested. Includes Makita RPM, Basic Conversions and Joystick Controls.Onefinity Cheat Sheet.pdf (508.9 KB)


I like what you did there with the Joystick controller so I misappropriated it. I am thinking of engraving this on a pull out I have in my top drawer for mousing. Here is how it carved. This was done on a scrap piece of MDF with a few coats of Pecan Poly satin stain.

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