How to Make a Sizing Gauge

Sizing Gauge Header

Hey all,

Most of you know, I am a tool and gadget junkie. I like things that make my jobs quicker and easier. In the next few posts, I am going to cover ring sizing, both sizing up and sizing down. If you have been making jewelry for any amount of time, you have friends and family that bring you their jewelry that is broken, bent, bruised, dirty, or that doesn’t fit correctly.

So in the next few blog posts, I will show you an example of sizing a ring down first, then sizing up. First though, I am going to show you how to make a quick tool that will make this job a little easier. We are going to make a sizing gauge that you will make once, mount on your bench, and have and use forever.

I have mentioned to you before, I don’t really work in sheet metal gauge, I work in mm.  People ask me all the time “What gauge sheet or wire did you use on this”….. well, I broke down and purchased a Sheet Metal Gauge so I can reference the thickness from time to time for you.

I started this project with a 0.8mm (20 gauge) piece of brass that I had laying around. Feel free to use whatever metal you like.

General gauge Sizing Gauge-1

Next, cut and file to size, in this example, I used a piece that is about 1.25 inches (31.75mm) x 0.5 inches (12.75mm). I filed the pieces and sanded the edges a bit, just because I like things that are finished looking.

Sizing Gauge-2 Sizing Gauge-3 Sizing Gauge-4

The next step I did was to trace a line down the center of the piece with a Fine Sharpie and a 6″ Steel Rule, because I want this to look nice and even since I am going to have this on my bench for a long time.

Sizing Gauge-5

Starting from the center of the brass piece, I scribe a point at the center mark with a Scribe or Awl, and along the one edge, then joined the dots with my scribe.  With a 3 Inch Divider I measure the distance of the opening of the dividers at 2.5mm, and make a series of marks (dimples) along the center line and along the edge. 2.5mm is the measurement for 1 ring size. I am going to scribe a line in the brass from the center points to the edge points. I could scribe all the way across from the top to the bottom, but that isn’t necessary, I like the look this way.

 Sizing Gauge-7 Sizing Gauge-6

Sizing Gauge-8 Sizing Gauge-9

 Now what I did next was to scribe another line, half the length, in between the scribed lines. This is for 1/2 sizes. You will be dealing a lot with 1/2 sizes and even 1/4 sizes (but I don’t find 1/4 size marks necessary)

Sizing Gauge-10

The last thing I did was to drill 2 small holes into the gauge and mounted it to the front of my bench. Oh, I also rubbed the surface with 600 Wet-Or-Dry Sandpaper to give it a satin look, and give a contrast between the face of the brass and the scribed lines.

Sizing Gauge-11

Many Ring Mandrel have a sizing gauge engraved into them, but most of them don’t, so if you make one of these handy dandy gauges you will have it for years and it will always be right in front of you. In the next blogpost, I will show you what to do with this.

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Now go make something useful!


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5 Responses to How to Make a Sizing Gauge

  1. Linda S August 31, 2016 at 10:56 am #

    Another great tip! Thanks!

  2. Mary August 31, 2016 at 11:20 am #

    Thank you! Very interesting; I look forward to the next blog!

    • Doug Napier August 31, 2016 at 4:38 pm #

      Thanks Mary.

  3. Lori August 31, 2016 at 12:53 pm #

    18g is 1mm….

    • Doug Napier August 31, 2016 at 4:38 pm #

      Thanks Lori, …… see the reason I don’t work in gauge. haha