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Thread Size

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11 replies to this topic

#1 bass master

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Posted 26 November 2018 - 09:40 AM

For us new tyers I think thread size is harder to understand than hooks. I came across this article in Fly Tyer magazine online. It helped me out a lot and I printed out the chart for a handy reference. I think its a good read and help.    https://www.flytyer....ng-thread-size/

#2 SilverCreek


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Posted 26 November 2018 - 11:55 AM

Thanks for posting.



"Discovery consists of seeing what everybody has seen and thinking what nobody has thought"..........Szent-Gyorgy


#3 redietz


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Posted 26 November 2018 - 08:50 PM

For us new tyers I think thread size is harder to understand than hooks. I came across this article in Fly Tyer magazine online. It helped me out a lot and I printed out the chart for a handy reference. I think its a good read and help.    https://www.flytyer....ng-thread-size/

It was ok until until it said "Denier gives us an exact method for comparing the thicknesses of different threads".  It doesn't.  It gives us a method for comparing the weight of different threads.  Since different materials have different densities, two threads with the same denier may have different thicknesses and two thread with the same thickness may have the same denier.


#4 tjm


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Posted 26 November 2018 - 10:28 PM

Yes, that article neglects to say that denier only gives comparative size within a material, as redietz points out, It also neglects to say that the naught system only compares diameters  within a brand, because there is no standard industry wide. Neither system is more accurate or less accurate than the other, because both are relative, If anything the naught system might be more accurate if the brand includes threads of several materials and all use the same units. All 72 denier threads may weigh the same but won't all be same diameter, one brand 6/0 might be equal to another brands 8/0.

For accurate communication we need to include brand name and material in our descriptions. (although for most work any thread would work) 

I'm not sure that some writers and editors understand either system because I have seen several pieces promoting the accuracy of the denier system that did not account for the different mass of different materials.

This guy has made a chart of some common threads for comparisons;


#5 Bryon Anderson

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Posted 04 December 2018 - 04:39 PM

This is precisely why I decided a long time ago to pick a brand and stick with it. I picked Uni-Thread and it has been my go-to for the entire 20+ years I've been tying.


I have recently branched out a little -- I prefer UTC 210 for streamers and bass bugs, unless they're deer hair, in which case I go to GSP 130.


Oh, and I do have a spool of 16/0 something-or-other that I use for tying Parawulffs, because otherwise the wing posts just get too bulky for the #16 hook I like to tie them on.


Hook choices -- same deal. I was a Mustad man for decades, except for a few forays into eBay/knockoff territory (some of which I deeply regretted). I've lately been turning to Wholesale Fly Co. for hooks -- can't beat their prices and they're strong, sharp, well-made hooks.


FWIW, there are valid studies that show that when people are offered too many choices, they report feeling more unhappy. :)

"... trout do not lie or cheat and cannot be bought or bribed or impressed by power, but respond only to quietude and humility and endless patience." -- John Voelker (aka Robert Traver), Testament of a Fisherman

#6 Woodenlegs


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Posted 23 December 2018 - 08:14 AM

What issue is this article in?

#7 utyer


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Posted 23 December 2018 - 12:02 PM

Thread:  In fly tying threads, there are two commonly used terms related to size.  The ought term was used back when most threads were silk, and the more oughts the finer the thread.  In fly tying thread that looked like this 3/0 thick, 6/0 finer, 8/0 very fine, and so on.  


Denier began to be used as threads of different fibers were introduced.  The denier was a measurement of the weight not the diameter of the thread.  Different thread material would have different weights, and two threads of the same denier might not be the same thickness.  


Both these measurements were a product of the thread industry and simply adapted by the vendors of "fly tying threads"  


I was introduced to a DIFFERENT thread about 10 years ago that is not from any fly tying vendor.  Since that time, I have not purchased any "fly tying" thread.  What I am now using is Gutermann Skala thread.  This is a polyester multi-filament thread, which comes in 3 sizes.  It does NOT come on standard fly tying size spools.  For me that is not a problem since I use a Nor-vise Autobobbin, and re-spool all my thread anyway. 


This thread is available in LARGE spools up to 21,000 yards, and the smaller spools are 10,900 yards, and 5,400 yards.  While they do comes in dozens of colors, buying any single 10,000 yard spool is a lifetime supply.  I simply buy white, and use a Copic or Sharpie marker to color as needed.  


The big advantage is the cost.  A 5,470 yard spool sells On-line for  8.25 from the distributor  (Oshman Brothers.)   The price works out to be  15 Cents a hundred yards.  The three sizes that this thread is sold in are equivalent to  135, 118, and 72 deniers.  The measurement system used for this thread is a "Tex" number which when multiplied by 9 is about the denier.  In use, I find the thread are a bit thinner than what you would expect, and more than strong enough for my needs.  


One "other" thread or floss if you prefer, that I use is Gutermann Bulky Nylon.  This comes from Joann Fabrics, on a 1100 yard spool, and with a coupon is usually costs less than 4.25.  This cost per 100 yards is less than 40 cents per hundred.  I do by this in several colors, and use it in place of floss for bodies, and for tying larger flies for Bass and Saltwater fish.  

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#8 Ephemerella


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Posted 24 December 2018 - 10:05 AM

And to add to the confusion, in addition to denier (weight) and the ought system (diameter from same manufacturer), the construction of the threads differ from manufacturer to manufacturer, and from thread type within the same manufacturer.


For example Danville is spun (twisted) nylon, which can be un-twisted, to get a flatter lay of the thread, but is consequently weaker. Other manufacturers use bonded polyester, where the strands are twisted, like Danville, but then bonded (I'm guessing using heat) so the thread cannot untwist. That thread construction is a little stronger, but can never be untwisted to get flattened. And then there are the various gel-spun products and Kevlar...


Perhaps buying a few spools of each kind of thread (really they're only a buck or two) and find what you like for each purpose. You may find you like one size and construction for one purpose, but another for a different fly. Thread preferences are a bit like religion or politics - you understand and like yours, but that of the other people remains a mystery...


#9 flytire


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Posted 24 December 2018 - 10:45 AM

as bryon anderson wrote above "This is precisely why I decided a long time ago to pick a brand and stick with it."


i use 2 brands of thread - veevus 12/0 and danvilles 6/0. i no longer have to worry about aught vs denier of which i really dont care too much about

The fish care less than we do!

#10 tjm


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Posted 24 December 2018 - 12:18 PM

We can make it as complicated as we want or just use one thread or follow the recipe given in a pattern, but I doubt any of us will understand the thread sizes or need to.

It gets more confusing the more brand-material-sizes  you look at because long ago each community set it's own standards and had separate standards for each fiber.
Tex and denier are both metric mass based systems, with denier being mass of 900 meters and tex being mass of 1000 meters so conversion from one to anther is simple arithmetic, but there are also a weight system, a cotton count system, Government thread sizes, linen count system, wool count system, Commercial thread sizes, Gunze Count system, ticket number system, far east size system, silk twist system; all of which are only meaningful when compared to the same material in the same system. Conversion charts have to be specific to the material, and none of the common systems of sizing are diameter based.
I have never really known what size system rod winding threads, "A"-"D"-"E", relate to, silk most likely but maybe another system specifically for rod building.
The Tex system is the least ambiguous and most logical system to use when communicating a thread size but until there a world wide agreement on that we can only find a brand-material-size that suits our purpose and stick to that thread or go by the thread brand-material-size specified in the pattern recipe.


#11 CasualAngler


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Posted 24 December 2018 - 03:42 PM

I use what's recommended in the Fly recipe. So far, that's been mostly UNI 6/0. The 3 spools of UTC I bought
(1-70d, 2-140d) were mainly for Color. UNI works with my hamfisted tying style better than the UTC does.

Alan :o

#12 Poopdeck


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Posted 24 December 2018 - 06:30 PM

I agree with tjm! thread need not be complex. I use 6/0 and 8/0 uni, 70, 140, and 210 Ultra thread. I tie down to size 20 flies and up to 6 oz buck tails with these.

Utyer, I have been using skala for my furled leaders for years. Never though of tying with it. I'll have to give it a shot.