Related Web Pages
- Adjustable Ring Size Chart
- Ring Size Conversion Chart – Convert your ring size to the ring size used in other countries.
- Q&A: Rings
- Ring Blank Chart
- Ring, Bracelet and Bezel Mandrels
- Saddle Ring Pattern
- Stones and Stone Setting
- Texturing Metal
Determine your ring size and find the inside diameter of that size.
If you are trying to determine the diameter of your ring size, using a ring sizer, ensure that you measure exactly in the center of the horizontal and vertical lines – otherwise, your measurements will be off (you’ll frequently get different numbers) – especially with plastic sizers.
There are several charts, out there in the interweb world but, of the five, that I surveyed (and I only checked one size – 11), four of them had different numbers from one another. There are international standards set by ISO (a worldwide federation that sets international standards). The standards for ring diameters are found in publication ISO 8653:1986. It costs about $38.00 US. I’ll guess on diameters for now – or use one of the many charts (whether right or not, is anybody’s guess) available online. Just search for: inside ring diameter chart or something like that.
Determine your sheet metal gauge and use a chart, like my B&S Gauge Chart, to determine the size, in mms of your metal gauge.
Add .5mm if the metal used is over 4mm wide.
To figure out your own sizing (instead of using the chart) here’s the formula: (A [inside diameter] + B [metal thickness])* pi . Pi is(3.14159265359+). You can round Pi down to 3.14 if you want. In summary, the formula is: (A + B) * Pi = blank length (+ .5mm if over 4mm wide).
Other considerations: how much metal you remove from the ends, how you mark the metal, how cleanly you cut the metal so, sometimes we need to stretch (or shrink) our ring blanks – all contribute to size variences. This is, just one of the many reasons, why I make adjustable rings. Not only is the sizing iffy but, people’s fingers change size throughout the day, month and year – not to mention over a lifetime!
Want to skip the math and too tired to look at the chart? Here’s a Ring Blank Calculator by Mordent Design.
Check out these books for further information:
- Jewelers Resource: A Reference of Gems, Metals, Formulas and Terminology for Jewelers (Revised Edition) (Jewelry Crafts) by Bruce Knuth.
- Jewelry Concepts and Technologies by Oppi Untracht.
Or visit my Links: Books page for other great jewelry making books.