I am building my first large diameter rod. It will be a heaver. I have been reading the posts here, some books I own and researching thread strength between the various sizes. In general my understanding was that D was not necessarily stronger than A - that it was the actually the overall number of wraps on a guide that provided the inherent strength. It makes sense and I agree. What I assumed is that A was stronger because it provided more wraps per inch than D and its relative break strengh relative to D exceeded D's break strength on a relative width basis. What I have read is most use D because of its ability to better withstand abrassion but was not neccessarily stronger than A. But there are others that have just plain said -- nuff - D is stronger. So being the curious type I looked up all the information and here is what I found. (you can go to gudebrod and do a search and get the same info). I didn't look up other thread mfr's to see if there was a similar difference;

Regular Nylon thread
(Size)/(Dia (mm))/(Break Strength (lbs))
A / .152 / 2.7
D / .264 / 7.4
E / .305 / 11.6

It takes roughly two winds of A to equal one wind of D. However the relative break strength of A is roughly only 1/3 that of D. So two winds of A are still only 2./3 break strength of the one wind of D. So A when compared to D on relative width is not as strong. It falls roughly 2lbs short. Worse yet is that two winds of A is slightly wider (.16) of that of D so the actual break strength on a relative width basis is even less than 2/3.

Please review my math -- but it seems that not only is D stronger than A on a per thread basis -- but on a comparative width basis, D is still stronger than A.

Anyway -- I use mostly A as it finishes much nicer than larger diameter threads. However -- I have decided on truley rugged rods -- I will use D -- stuff appears to be just plain ol' tougher than A in every way.

Feedback / Comments welcome & encouraged. Would like to get others input. If my math etc is wrong please let me know.

Thanks
Mark

Mark - you did an awful lot of work and I admire your tenacity. There are a lot of myths in our profession but being a rather simple man I just say "If it works for you then don't change it just because someone says you should." Botton line on this issue is that either A or D and anything in between will hold up to fishing pressure if it is done corrtectly.
I do an awful lot of rods out her for fishermen who go after the big Yellowfin Tuna caught down in Baja I usually do an UW in A then a first over wrap in A or C/D and a final over wrap in C/D. I have also done everything in A and have never had a failure. Thanks for your hard work the facts are what they are. I for one give you a 10.

I'm with you. Give me D. I use A for underwrap, then D for the guides.

I've used nothing but A for all the guide wraps for over ten years with no failures, I do coat each layer with rod finish however. This is on strictly saltwater rods used offshore S. Calif.

The problem is, the breaking strength of thread is not relevant here. You can't pull a guide off a rod, whether it's wrapped with A or D thread. It's a non issue.

The only advantage you get with larger thread is greater protection from abrasion.

If you want to do a relevant test, wrap 50 guides each with A and D thread. Suspend the rod and hang weight or nylone twine with scale on the guides and see how much force is required to actuall pull the guide off the rod by breaking the thread. What you're going to find is that you will completely deform/destroy the guide before you'll bust either thread.

.........

I am lost Tom when you are talking about abrasion. When there is enought abrasion to get to the thread wouldnt damage cause by water getting into a semi closed environment be the real problem. You are right about pulling a guide off though it would take mega psi. I think Marks point on this issue is more a wake up call to all of us who hand out answers with out a factual basis ie "debunking the myth" I dont know I am probably wrong here too. I live in a world of keep it simple.

I understand, it's just that I never understood the argument over which is stronger or which makes the stronger wrap as it doesn't matter.

I've had some of my big trolling and stand-up rods used on charter boats where they get very rough treatment. I've seen some that had been bumped, abraded, etc. to the point that gouges had been cut down into the thread. I was glad that those rods had been double-overwrapped with D thread.

But as far as keeping a guide on the blank, we're not having failures with A thread wraps. Guides aren't being pulled out or through the wraps. Thread isn't busting. So while it's an interesting discussion, it's not particularly relevant insofar as the type strength needed on a fishing rod for a guide wrap.

But it is nice that Mark took the time to gather this info. One more bit of rod building info we'll have if we ever do need it.

..................

Thanks all -- I am glad I was able to stir up some interesting dialogue. I think Doc made a great point about giving out answers without clearly articulating the basis for the recommendation. I have probably been guiltly of it myself from time to time. It is interesting that in all the books, articles and posts I have read not one articulated the "why" clearly -- i.e. insufficient detail in the reasoning. This is the first time that it has been explained to me in a manner that actually makes sense and at least for me puts the controversy away once and for all. If anyone had previously said to me -- you don't need to care about the relative strength of A vs D because either when applied with sufficient number of winds and finish is stronger than the guide, maybe even the rod itself would have been sufficient for me to understand the point and move on.

To summarize (and correct me if I am wrong)....

- A finishes nicer - use most applications
- D is recommend for use on rods that will receive rough treament (handles abrassive wear better)
- A guide finished properly with either A or D will not break away from the rod. The stress required to break a guide through the thread will break the or deform guide or break the guide or break the rod before the thread will fail.


All great info -- I think others will find this useful. Thanks!

Mark

Now I need to figure out this guide thing! .....LOL

I think you summerized it very well.

.......

Prior to the internet and some other recent things, there was very little way to get rod building information spread around. What did get out came from the few books published and a little club magazine called the Rodcrafter journal. For all the good it did, the journal also did some very bad things. Most all the myths such as the one you mention here got their start in the journal. The trouble is that they just ran whatever somebody submitted. It didn't have to be true or accurate. You submitted it and there was a pretty good chance it would run in order to fill the pages with something. All today's misunderstanding about having to put the spine in a certain place started with the journal. It was wrong, but it will take a lifetime to get all the bad info beaten back down. The myth on thread holding power also came from the journal. You can go on and on and on with all the bad info that came from there. Don't get me wrong, some good info came from there too. But the bad stuff has solidified and will take years and years to wipe from the face of rod building. Remember, if it's in print, it must be true.

Best thing about Rodmaker IMO, is that most of what ends up running there is actually true.

Size A looks better than D....but D is quicker.

I love the fact that I had the Rodcrafters Journal as a learning tool and would never bash such a publication on an open forum. That publication introduced me into rodbuilding.

Today is a different story.

Like the responce to this thread. Now sense it was decided which weight thread to use. What about adding this to the equation . Is it better to use multiple coats of thin finish or one coat of high build?
Good Wraps Bob

I didn't see anyone bash the Journal. In fact they only said exactly what the journal said in an older issue. "This is not an engineering journa;, it's a rodcrafting journal and you should not believe everything you read here." That is a direct quote from the journal about 8 or 9 years back. I bought some old back issues from a guy getting out of the business and was more than a little surprised to read that, but it's right there in black and white from the journal editor. So it's not bashing it's just mentioning that a lot of the information in it isn't necessarily accurate. That's not bashing.

I would never bash any publication or person either. At least we agree on that. Stating facts in a civil manner is not bashing. Let's also keep that in mind.

Heck, suffice it to say, "We're on the road to improvement." And Tom's site and Rod Maker Magazine are definitely helping us onward and upward.

Amen!

This is what this site and RodMaker is all about discussing on how and what to do on certain situation. Just remember in many situations there is more than one way to do a application and one way is no better than the other. Where the difference come in play is the one who is doing the job. One application maybe easer for one party than another. So lets all share what we know and decide for our selves which is the easiest and improve that method. Ijust wish we had a spell check here. I hate going to word perfect to correct my miss spelling
Good Wraps Bob

Ditto Bob! I think one of the most repeated answers on this forum has to be, "You have to practice and discover what works best for you."

Since finding this site, I have learned more in a short time, than my father did in most of his life time. It use to be, you learned from someone, then you went off and done that way forever, or until you either discovered or someone showed you a better way.

I have tried many of the suggestions I have read on this site. Some I have entered into my everyday arsenal. Others, I have dismissed for one reason or another, but have read VERY little, that I have not considered either worth while, or at least information worth pondering.

Thanks for the thread!

Regards......Doug@
TCRds

AMEN to the various realities that have been discussed above regarding thread tensile strength and wrapping restraining strength. Myths DE-BUNKED !!

Mark Gordon, you have independently brought to a conclusion an explicit solution which has been alluded to countless times in rod-building. But you are the first Author I have seen who actually persisted to the point of completing the essence of the math. THANK YOU for your diligent pursuit of the Truth.

The Old Myth was that E-size wraps were not only stronger than D > C > A > OO-silk, but that the heavier threads were NECESSARY. Then somewhere along the line (probably in the 70's when Dale Clemens & RodCrafters did to rod building what e-mail did to personal communication), someone created a New Myth that said: A-size wraps are "just as strong" as D or E. And by EMPIRICAL evidence, all the rods built with A thread that had not failed served as evidence that this "just as strong" clause was true.

The Truth is NOT that the wrap strengths are EQUAL, but that ANY of the thread wraps have a strength that is more than SUFFICIENT for our rod-building applications in an overwhelming majority of the circumstances, forces and hazards actually encountered.

Most of our rods are built well above the threshold of failure, and only rarely come close to experiencing forces capable of producing failure. Rough handling of a rod, or accidental bashing or "high-sticking" probably puts more force on a guide wrap than most fish fights. And even then, that force is limited by the weakest link in the system, which is the fishing line itself and the regulator of that tension, which is the reel's drag (which is assumed to be operating properly - LOL). Overbuilding the components of a rod is basically the industry standard. It's bad for business & pleasure when things break.

Back around Labor Day weekend 2004, while I was here in Northern Florida waiting for Hurricane Frances to hit, there was a discussion that asked what the proper thread tension should be.
[www.rodbuilding.org]

In it I attempted to derive an expression for the absolute pressure on a wrapped guide, but soon realized that without having a reliable device to actually measure the thread tension, and the resultant pressure around the rod tube, that all my pontificating would be just so much speculation. And we had enough of that already.

Mark, you managed to limit the mathematical expression to the essential variables (thread tensile strength times the # threads per axial length) and provide a relative expression for making a valid comparison, devoid of the other elements in the system (blank diameter, guide-foot length) which are constants which just drop out of the equation for a given guide mounting. Thanks. You're not the first in history to do that, but you are the first I have seen at RBO to put up some numbers.

The note on which I would like to end is that the laws of physics and chemistry underlie a great deal of what makes rod-building work. Those laws are operating 24/7 whether we are aware of them or not. Careful understanding and application of their underlying principles makes for better rod-building. Craftsmanship should be a logical and artful design-related application of those principles, and not simply a propagation of the status quo. Knowing what does - or what doesn't - make a difference will streamline our rod-building and (some of) our discussions.

-Cliff Hall, Gainesville, Florida-U.S.A.-