Today when I was making a necklace, I wanted to use .024 Gold Wire because the Murano Glass Beads (as I wanted to use a lot of them) were a little heavy for smaller wire. Now do not be confused, I am talking about beading wire such as we use for stringing which is measured in inches contrary to wire for wire wrapping and head pins which are measured in gauges. Though admittedly many of the headpins convert the gauge to inches. Go Figure!
So when I found this formula, it makes sense to me. So for most Venetian Beads 19 gauge and anything with a higher number will fit.
My preferred sizes are always the 19 or the 20 gauge.
Multiply the outside diameter (OD) of the wire or cord by the number of times you will pass it through the crimp.
Choose a crimp bead with an inside diameter (ID) slightly larger than double the wire.
A simple chart might be easier. I know it is for me.
For example: if the OD of the wire is 0.013", and the wire will pass through the crimp bead twice,
the ID of the crimp must be slightly larger than 0.026" (0.013" x 2 = 0.026").
I wanted to use .024" wire because I am making a heavy necklace.
And I want to send the wire back through the crimp tube to secure the necklace.
So .024 X 2 = .054"
.054" = 1.37mm
So I need to choose a crimp that has an inside diameter (ID) slightly larger.