Hello,

What does 80 million modulus mean? I don't recall ratings on rods 20 or 30 years ago; we just picked what felt good in the weight and rating desired. I therefore have no frame of reference for modulus count, IM6, 7, 8, etc; or ton.

What do these mean in practical application?

Can anyone help?

Thanks!

Josh

It is just marketing lingo for the most part, the same way 30 ton ,40 ton, IM6, IM7 and so on.  From what I read somewhere is that the original IM designation came directly from the source of the graphite but since there is no industry standard and companies use different sources for materials, they are pretty much free to say whatever they want.

Basically the higher the modulus count the stiffer and more sensitive the blank is, but it could come at a cost on the durability.

55 minutes ago, georgeyew said:

Basically the higher the modulus count the stiffer and more sensitive the blank is, but it could come at a cost on the durability.

 

1 hour ago, smalljaw67 said:

It is just marketing lingo for the most part, the same way 30 ton ,40 ton, IM6, IM7 and so on.  From what I read somewhere is that the original IM designation came directly from the source of the graphite but since there is no industry standard and companies use different sources for materials, they are pretty much free to say whatever they want.

Thanks guys.

So what's a low modulus?  20 million?  What's considered high modulus?  What's the highest and lowest modulus on the market today?  If I have a range, I might be able to work this out in my head.

Thank you,

Josh

The lowest graphite I've seem is 25 tons (Abu Garcia) and IM6 . The highest is 90 Million (BPS) and IM10 (Shimano). I think different brands have their own version of the rating.

Here is a write up from allfishingguy.com:

High Modulus

Carbon fibers are classified by the tensile modulus of the fiber. Tensile modulus is a measure of how much pulling force a certain diameter, in other words how much load per square inch of cross section ("stress") the material can tolerate before breaking. The English unit of measurement is pounds of force per square inch of cross-sectional area, or psi. Carbon fibers classified as "low modulus" have a tensile modulus below 34.8 million psi (240 million kPa). Other classifications, in ascending order of tensile modulus, include "standard modulus," "intermediate modulus," "high modulus," and "ultrahigh modulus." Ultrahigh modulus carbon fibers have a tensile modulus of 72.5-145.0 million psi (500 million-1.0 billion kPa). As a comparison, steel has a tensile modulus of about 29 million psi (200 million kPa). Thus, the strongest carbon fiber is about five times stronger than steel. 
The term graphite fiber refers to certain ultrahigh modulus fibers made from petroleum pitch. These fibers have an internal structure that closely approximates the three-dimensional crystal alignment that is characteristic of a pure form of carbon known as graphite. 
    Modulus is a measure of stiffness, how far the material stretches for a given stress. Modulus is the ratio (espressed in millions of psi, "pounds per square inch", a measure of a force on an area) between stiffness and weight of the graphite blank. The higher the modulus, the more energy the rod can store and release. The energy is a way of saying the speed and the power of the rod. Think of a swimmer on a diving board and try to imagine to variate the properties of the jumping board and you will see what it is. Some also simply by saying that modulus is resistance to flex and the higher the modulus the stiffer the rod. Beware, though, the higher the modulus, the more expensive is the blank and also more brittle the rod after an impact. 
    There are many types of carbon fibers: IM6, M8, M55, M40, M40J, M46J, T300, HR40, and more. Each have their own properties: which are the modulus and the strength. Good fishing rods have generally speaking a high modulus, a high strength, and intermediate percentage of fibres. 
The modulus is given as force per unit area, for a material, so saying 33 million modulus or 33 Msi means 33 million pounds per square inch of material.

• High-modulus, type HM (modulus between 350-450Gpa).
• Intermediate-modulus, type IM (modulus between 200-350Gpa).
• Low modulus, high-tensile, type HT (modulus < 100Gpa, tensile strength > 3Gpa)
• Superhigh-tensile, type SHT (tensile strength > 4.5Gpa).

The less a material will bend before it begins to fail the higher the modulus. 
High modulus materials can be used to make soft rods, and conversely, low modulus material can be designed into making stiff rods.
The higher the modulus of graphite, the higher the stiffness, the lower the strength. A 57 million modulus graphite rod will be lighter and stiffer (therefore more brittle) than a rod rated at 44 million modulus.

• IM 6 graphite is approx. 33 million modulus
• IM7 graphite is approx. 44 million modulus
• IM8 graphite is approx. 51 million modulus

Modulus alone does not make a good Rod. 80mm is way too high to be use 100% in a Rod. Just marketing. 

I look at the graphite numbers simarly to speaker manufacturers who call their speakers like "400 watt speakers" vs "1000 watt speakers" = no relation to actual performance or quality.

Hold it, hold it, hold it, bu,bu,bu, we´s got ´nother rating ! HMG

Of course as DVT said, HMG or IM rating pretty much mean little when it comes to performance, feel or sensitivity.

It's not irrelevant but is way over hyped. Graphite modulus , scrim, resin , mandrels, design all come together to make a Rod blank what it is. At least modulus is a real thing. IM, SC, RX .... Are all subjective terms. 

The strength of the fiber doesn't indicate the strength of the composite without considering the percentage of resin to fiber that holds everything together into a tubular construction.

Scrim is net or pure resin holding layers of fibers together, Scrimless means no net resign layers instead nano bonding is used. Every rod blank makers has their state of the art technique to achieve light weight construction that is both durable, flexible and transmits vibration easily.

Tom

 

Thanks guys.  Lots to go through here!

Regards,

Josh

Well if it feels good...I buy it.

Here's a good thread from way back at the beginning of BR.  Make sure you click on and read the links.

 

As I recall, it was a blank company called Hexcel that started using the IM6, IM7, IM8 designation for their rod blanks.  Rumor had it that it took them 6 tries t get a blank they liked, so that's where the IM6 came from.  Don't know about that part.  Anyways, as is typical in business, other companies saw that designation and saw it as a good way to market their rods. Problem is, there is no standard for what each designation means, so all IM6 rods are not created equal.  Consumers started buying into that way of rating, and it has caused plenty of confusion.  In general, it means nothing, unless you are familiar with that particular companies was of rating.

 

Modulous rating and ton rating are both ratings of strength of the graphite, with Ton being a worldwide "standard" and Modulous being a US "standard."  I say "standard" because, similar to IM ratings, there are no standards to who uses what in rod building.  In general, the US blank manufacturers use Modulous rating while other countries use ton.

 

Finally, Modulous refers to the Modulous of Elasticity.  This is the measurement of force per area (I believe rod ratings are PSI) which is required to cause elastic deformation failure, in plain English that means it will stretch and break.  The higher the modulous, the less graphite is needed to get a similar "stiffness" which leads to a lighter and more sensitive rod.  However, as mentioned above, it is far from the only consideration in selecting a rod or blank.  As you get higher in modulous, the blank will also become more brittle, which is where scrim and resin make a big difference.  What it comes down to, is finding a rod (or blank) lineup whose characteristics meet your needs.

All in the links of my post.

13 hours ago, Florida Cracker2 said:

Well if it feels good...I buy it.

Me too.  Problem is that some of the best feeling rods haven't been the most durable.  I recall one from BPS I had once -- the thing was really light but snapped quickly.

The Jimmy Houston rod (80 million modulus) I just bought for $10 on clearance originally sold for $60 to $80, and I expected it to bust.  Spent a day trying to break it and couldn't.  Still trying, though!

Regards,

Josh

Just curious if u know the modulus count on rt3 graphite have a salmon rod made from rt3 graphite.