As longtime members know, I have commented a number of times about misleading thread sizing. I didn't make too big a deal over it because, also as many people know, I have a connection with UNI Products. Moreover, it was impossible for me to contact other brands to ask specific questions (although I had measured samples). Denier is the weight in grams of 9000 meters of thread, so threads of the same material and denier are the same "size."
Now a neutral observer, Chris Helm, has published a chart in Fly Tyer based on information from the brand companies. A few examples: Polyester Threads: Bennechi 12/0 --- 70 denier Griffith 14/0 --- 72 denier UNI 8/0 --- 72 denier Bennechi 10/0 --- 120 denier Gudebrod 10/0 --- 45 denier The smallest of the polyesters? Gudebrod 10/0. The smallest spooled thread (monofilament)? UNI Caenis --- 20 denier. The smallest, strongest, thread? 3-way tie, all 50 denier gel spun: UNI Cord 12/0, Bennechi Ultra Strong, Wapsi GSP. Unfortunately, for those who have the full table, there are a number of errors in the "nylon" categories. UNI 6/0 (135 denier) and UNI Big Fly (440 denier) are polyester, not nylon, and UNI has a 70 denier nylon (omitted). cheers, Paul http://www.galesendpress.com Paul Marriner Outdoor Writing & Photography. Owner: Gale's End Press. Member: OWAA & OWC. Author of Stillwater Fly Fishing: Tools & Tactics, How to Choose & Use Fly-tying Thread, Modern Atlantic Salmon Flies, Miramichi River Journal, Ausable River Journal, and Atlantic Salmon.
