Chain making article sans editing

Common chain terms

AR – Aspect Ratio

ID – Inside Diameter

OD – Outside Diameter

WD – Wire Diameter

AWG – American Wire Gauge (In the United States, includes but not limited to: copper, sterling, gold, gold-fill, Argentium, aluminum, craft wire)*

SWG – Standard Wire Gauge (in the United States, includes but not limited to: stainless steel, galvanized steel. In the United Kingdom & Canada includes precious metals)

Starters

Knowing how to weave rings into intricate patterns is only half of the craft of making chains. To make a great looking chain you must know the optimal ring size to highlight the chain pattern. If your rings are too large, your chain is floppy and the pattern is lost. Conversely, if your rings are too small your chain is inflexible or may not be able to be woven at all. Many times you’ll see references to ring sizes in books or websites, sometimes referred to as Key numbers or more commonly, Aspect Ratio (AR). The AR is the relationship between the Wire Diameter (WD) and Inside Diameter (ID) of the ring. As important as the AR is for chain making there usually isn’t one AR for any particular chain weave. With few exceptions there is usually an AR range for most chains, what number to use in the AR range is a subjective decision. When you see an AR range for a chain the lower the number in the range indicates the tighter weave, conversely the larger number in the range indicates an airy weave. One important thing to remember and the real beauty of AR is that the ratio remains the same regardless of the wire you are using; gold to copper to galvanized steel, AWG or SWG the AR is always the same.

Finding the Aspect Ratio

To get a chain’s AR you need…math – sorry, math. However, the formula is very easy and you will find yourself using it over and over when making chains.

Here’s the basic formula: ID / WD = AR

Same formula:

WD*AR = ID

Ditto:

ID/AR = WD

[So, how does it work? ] Let’s say you want to weave a Byzantine chain that you saw in a magazine but you prefer to make it with a larger or smaller wire than shown. Looking at the AR formula you can see there are only three data points needed to make all your chain fantasies come true.

DisclaimerI strongly advise making just enough rings to weave a sample chain and make adjustments to your ring sizes as needed or desired – remember AR is only one piece of equation.

Let’s say the magazine chain is: 16awg copper rings with an ID of 4.25 mm, using this information you can do the AR calculation. For your convenience, I’ve included a chart that lists some common wire diameters** (WD):

AWG

Fraction

MM

12

.0808

2.05

14

.0641

1.63

16

.0508

1.29

18

.0403

1.02

20

.0320

.813

22

.0253

.643

To find the AR of the magazine chain (16awg =1.29mm & 4.25 ID rings), plug the numbers into the formula:

ID / WD = AR à 4.25 / 1.29 = 3.29

Now you know the AR of the magazine chain is 3.29. To make a larger chain, let’s say with 14awg wire. You would use the basic formula, re-arranged to use the numbers that you know to find the new ring ID for the 14awg wire – it’s not hard.

Finding the Inside Diameter – Increasing the wire gauge

From the chart above, you know the diameter of 14 awg is 1.63mm and from your previous calculation you know that the AR for the magazine Byzantine chain is 3.29. Plugging in the known numbers into the formula, you can get to the new ring ID for a Byzantine chain using 14awg wire.

WD * AR = ID à 1.63 mm * 3.29 = 5.36 mm

Next, use the provided [separate] chart to find the mandrel to use for a 5.36 mm ID ring. There isn’t a perfect match; you can round down and 13/64th (5.15mm) mandrel or round up and use either a 5.5mm or 7/32th inch (5.5mm) mandrel. I usually round up when I can’t find a perfect match (see Disclaimer above). The ring size for a Byzantine chain that I finds looks the best using 14awg wire is made with a 7/32 (5.55 mm) mandrel. Make a small chain sample before cutting all your rings!

Finding the Inside Diameter – Decreasing the wire gauge

Let’s go down a wire gauge (18 gauge) and determine a new ring ID, the WD for 18 awg wire is 1.02mm and the AR for the magazine Byzantine chain is 3.29

WD * AR= ID à 1.02 mm * 3.29 = 3.36 mm

The ring ID for the 18awg wire comes out to 3.36 mm; using the provided chart to find which mandrel to use based on your calculation you can see that there isn’t a 3.36mm mandrel or equivalent imperial mandrel in that size. You may want to go down to the 3.25mm mandrel or up to 3.5mm mandrel. Your mandrels, your wire, the wire temper, or simply your preference will ultimately determine which size ring you think is perfect or not. Again, make a small sample chain and adjust as necessary.

AR, Wire, Mandrels & Experience

Admit it…it wasn’t hard after all….

Admit it…it wasn’t hard after all….Most of the time the AR you use to determine the ring ID works fine, but sometimes you will find that your chain is a bit tighter or a bit looser than expected despite the fact that you’ve double checked your math. What happened? Your unexpected results could have been caused by a number of things including the real gauge* of the wire, your mandrels or the wire temper.

You will find that not all wire is created or labeled equally, sometimes your wire measures perfect when using a standard wire gauge or, sometimes it’s a tad bigger or smaller than what it’s labeled. Silver, copper and Argentium are all measured using the AWG in the United States, in Canada and the UK the same wire measured using the SWG system. Add in the sad fact that the same gauge wire in different metals or, wire from different companies don’t always measure out to the same size*. ACK!

If you use wood dowels for mandrels, each time you use them they compress and will get a wee bit smaller which further complicates the task of determining the ring ID for the chain you’re trying to weave. You can buy steel mandrels made specifically for making jump rings or you can buy a set of Transfer Punches (available in both metric an imperial sizes), or use aluminum knitting needles to use as your mandrels.

Wire temper is another part of hitting this seemingly moving target of ring ID. Dead soft wire wraps up nice but since it’s soft it tends to dull your saw blades a bit faster than other wire tempers. Occasionally you’ll have to defend your decision to use dead soft wire; some people don’t think it’s strong enough for chain making without soldering (so far, knock on wood I haven’t had any problems using dead soft wire for chains, note: I tend to weave chains at the lowest AR possible). Half hard wire is easier to cut, but ‘springs back’ a bit when you release the tension from your coil making your rings a little bigger than rings made from dead soft wire. Hard wire will spring back even further than half-hard – and don’t get me started on Spring Hard wire (YIKES!).

{Geez…I’ll just buy my rings, this is too much trouble…} Determining ring ID and making rings is time consuming, but making your own rings frees you to create your chain.

Personal Weave Notes

Here are my favorite Byzantine sizes using dead soft AWG wire

Weave Gauge ID

Byzantine 14 7/32

16 4.25mm

18 3.5mm

Romanov 18 3.5mm

Byzantine Web 16 4.5mm

Box Chain 16 15/64th

Byz Wave var. 18 3.5mm (caution: uses loads of rings)

Final words

My all time best piece of chain making advice is to buy some copper wire in a number of gauges and make prototypes of your chains (document your favorite sizes). The time and wire used for making samples will serve you well; you learn the weave without worrying what your rings will look like after you’ve opened and closed each ring several times, you will find your optimal ring and, you will have a small piece of chain or tail to use to start the chain instead of having to start anew

* When in doubt, use calipers.

** Wire diameter source: The Complete Metalsmith by Tim McCreight

*** I tend to weave chains at the bottom of the AR range, there just isn’t much leeway at low end of the range.

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~ by khmetalwork on July 27, 2008.

5 Responses to “Chain making article sans editing”

  1. THANKS!!! And I love your chosen picture for the header of your blog – way cool. 🙂

  2. Cool info! ~M

  3. Karen, this was a FANTASTIC article. I’ve been meaning to post it on the Chainmaillers’ Guild blog that one of ours was published, and then before I knew it another issue was out! (they never sent mine so I ended up getting it late from the newsstand). I think I will still post a mention on the blog with a link to this blog post, if that’s okay.

  4. Karen thank you for this great article. I hope you are feeling ok. You are always so kind and generous to answer questions. Am looking forward to looking at your beautiful pieces in 2009

  5. Karen, Thank you for the great article it answered my questions. Now off to the work table I go to see if I can put it all to good use.

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