A good while ago there was a discussion on thread strength of A vs D and I've been looking for it and can't seem to find it. What I was curious about was what was the difference in strength of wrapping, say, a 10mm guide foot with A thread vs D. The D is definitely stronger but you get less wraps than what you would obtain using A thread. So what would you use if you wanted the strongest wrap on that 10 mm foot?

Tom

Either, both are more than strong enough.
Norm

the number of wraps to cover guide foot times thread strength looks like it would give you the total wrap strength..we need to know each thread strength to figure the wrap strength..that,s just my guess..do you know the two thread strengts..

The butt end of your rod will break before the guide wraps do.

The reason I mainly asked is because one of my customers has had two wraps break on two different rods. The casting guides were in the power section of the blank. I was using Pro Wrap A nylon thread. Unfortunately I don't know the thread strength or where to obtain that information. He is very hard on his equipment that much I do know.

Thanks
Tom

When you say he had two wraps "break," do you mean the guide feet actually tore through the wraps? Or was this more along the lines of a guide shifting or moving under the wrap?

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

Tom Kirkman Wrote:
-------------------------------------------------------
> When you say he had two wraps "break," do you mean
> the guide feet actually tore through the wraps? Or
> was this more along the lines of a guide shifting
> or moving under the wrap?
>
> ............

Yes Tom the front wraps were cut through by the guide foot. it was a Fuji CLNAG -10 the guide was bent but not that bad.



Edited 1 time(s). Last edit at 04/24/2020 10:04PM by Tom Wewerka.

Tom here is a Gudebrod table concerning thread strength and weight. It may be of use to some people.
[96.30.27.81]
Norm

Thanks Norm I lost my copy and forgot where I found it to begin with.
.
Thanks again.


Tight Wraps & Tighter Lines

Bob,

New Bern, NC.

Is it possible that the guide was abused when pulled out of rod locker or was stepped on when on the boat deck? It may also be possible that the guides were too far apart in the butt section of the rod and thus did not spread out the pullout forces generated when the rod was fully loaded. In this case the angle of line would pull down on the guide ring bending it and lifting the toe of the guide foot which would either cut or pop a thread or two. This is just wild speculation on my part, but if true maybe an extra guide is needed to spread out the pullout forces. My best guess would be that the guide was abused.
Norm

Norman,
Copy that.

I agree that the rod was likely stepped on, or jerked out of a locker, thus bending the guide.

I am familiar with that guide and I don't believe that with the physics of the guide construction and the force direction of a line running through the guide could ever bend that guide before either the line broke, or the drag on the reel slipped.

If in doubt -- take another identical guide and tie it onto a broom stick using 2 layers of D thread. Then, put as much force as is possible for you to put on the guide by running what ever line you wish through the guide and see if you can get the guide to bend.

Unless, you have a manufacturing defect - I doubt very much that you will be successful in getting the guide to bend.

A double foot guide essentially forms a triangle - which unless one of the "members" is deformed, the triangle is impossible to deform.

Cut the guide off, clean up the rod blank, tie on a new guide, coat it, treat the rod with care and go back to fishing.

Best wishes.

p.s.
The strength of various thread sizes is somewhat akin to how much money can be held in a large plastic cup at a Casino from a coin operated slot machine.

It turns out, that for the classic plastic cup that casinos used to collect coins when they used coin operated machines as opposed to other types of machines would hold a given number of nickles, quarters, half dollars and dollars.

But the interesting thing about it is that - the cup held somewhat similar total values, no matter the coin that was in the cup. It all came down to the volume occupied by each coin. i.e. the cup was filled by the fewest numbers of coins when dollars were used, but the same cup took many many more nickles to fill the cup. Quarters and fifty cent pieces were in the center.

So, goes the process of wrapping a guide foot with size a, b, c, or d thread. Although a thread is much smaller than D thread, one can put many more wraps of a thread on the guide foot - hence giving somewhat comparable similar results with respect to attachment strength of the guide to the rod blank.

However - there is always an However -- the much larger diameter of the size D thread compared to the much smaller diameter of the A sized thread gives a very big advantage to the D sized thread - with respect to abrasion and rub wear on the thread when the rod is used as a rail rod.

So, if a rod is to be used for heavy fish, and is used as a rail rod, where the rod will normally be resting on a rail to assist the angler to land the fish - then the hands down choice for thread wrapping thread is the much larger diameter D sized thread.

If abrasion and rail rubbing is not involved - it is quite likely that the A thread will do just fine.

Especially in this case - with the particular guide in question, which is not a big heavy duty guide - the nominal choice for thread wraps would go to A sized thread.

Best wishes.

Got it Norm and thank you very much

Tom

Got it Norm and thank you very much. I copied the chart and am posting it for all to see.

Tom

[www.rodbuilding.org]

That works.
Norm

going by the thread diameter there would be 60 wraps of A thread to cover one centimeter and 40 wraps of D thread to cover one centimeter..and the D wrap would be much stronger..

ben belote Wrote:
-------------------------------------------------------
> going by the thread diameter there would be 60
> wraps of A thread to cover one centimeter and 40
> wraps of D thread to cover one centimeter..and the
> D wrap would be much stronger..


almost twice as strong as the A wrap

Ben,
Are you sure that the 40 wraps of D thread would be stronger than 60 wraps of A thread?

Try this test:

Take a broom stick which would be tough enough to withstand the rigors of testing.

Then take two identical two footed guides in a size - say 10 or 20.

Then, clamp the broom stick into a vice. Then take a 200 lb spring scale and using 200 lb test line, tie the scale to the guide and attach the other end of the spring scale to an expanding press. Turn the pressure up on the press and record the lbs pressure necessary to break the thread on the thread wrap for each of the builds. Let us know which one broke first.

My guess is that neither one would break with 200 lbs of force, but rather the 200 lb test line would break before the threads on either guide would break.

i..e. my point of the exercise is that you may be 100% correct with the thought that the D sized thread with fewer wraps is stronger. But, if the line that would be handled by the guide breaks well before either the A or D thread wrap breaks, does it make any difference?

Roger take a look at the posted Gudebrod chart. I’m sure their data is based on diameter and tensile strength calculation rather than actual breaking strength when wrapped on a guide. But the theoretically calculated data is clear. But you are correct in saying both are sufficiently strong enough.
Norm

like Norm said, i was just going by the gudebrod chart...

roger wilson Wrote:
-------------------------------------------------------
> Ben,
> Are you sure that the 40 wraps of D thread would
> be stronger than 60 wraps of A thread?
>
> Try this test:
>
> Take a broom stick which would be tough enough to
> withstand the rigors of testing.
>
> Then take two identical two footed guides in a
> size - say 10 or 20.
>
> Then, clamp the broom stick into a vice. Then
> take a 200 lb spring scale and using 200 lb test
> line, tie the scale to the guide and attach the
> other end of the spring scale to an expanding
> press. Turn the pressure up on the press and
> record the lbs pressure necessary to break the
> thread on the thread wrap for each of the builds.
> Let us know which one broke first.
>
> My guess is that neither one would break with 200
> lbs of force, but rather the 200 lb test line
> would break before the threads on either guide
> would break.
>
> i..e. my point of the exercise is that you may be
> 100% correct with the thought that the D sized
> thread with fewer wraps is stronger. But, if the
> line that would be handled by the guide breaks
> well before either the A or D thread wrap breaks,
> does it make any difference?
who knows what could happen if you should cross paths with Charlie tuna..lol.