: Hi Mike,

: Yeah, ounces per square yard is a heck of alot easier to
: understand.

: For most fabrics the old number system is thankfully going away.

: Bill H.

Hey Guys, Just thought I would help clear up some confusion on duck cloth/ cotton canvas weights. The wikipedia shows an outdated measuring system. Most of the weights on there aren't manufactured anymore. First there is a significant difference between " Ounce Ducks" and "Numbered Ducks".

Ounce ducks as the name suggests, are categorized by their approximate weight in oz. per square yard. (7oz 10oz 12oz.) Ounce Ducks are a single fill. Meaning, it's weaved using two single yarns. Single fill (SF) ducks have a looser weave and are more flexible in nature.

Numbered ducks on the other hand are referred to by the strange numbering system that probably made sense at one. Numbered Ducks are "Double Filled" or "Plied Yarn". Meaning, they are weaved with 2 double strand yarns. This makes for a much tighter weave, making the canvas much stiffer,stronger and durable. Weights of numbered ducks sold in the USA can vary but are approximately: #1 (30oz), #4 (24oz), #6 (21oz), #8 (18oz), #10 (15oz), #12 (11.5 oz)
http://www.bigduckcanvas.com/categories/numbered-ducks

I hope I've cleared that up for someone. We recently had a customer buy 100 yards of canvas for making kayaks as a boyscout project, he asked for 10oz but what he really needed was #10 and he realized his blunder once its arrived. That's when i began reading up on this topic. He sent us some plans to build so I think i might do this with my boys.

Best regards,
Shawn