Fiberglass Fly Rods: Old Glass vs New Glass Rods

Fiberglass fly rods- in the 70’s they were a big deal, but with innovations in rod design (read: Winston, G-Loomis, etc.), there was about a two decades where glass rods became few and far between.

However, check any fly rod catalog today, and you’ll usually see a few glass options listed. So for this episode of Ask North 40, we break it down and answer the question on everyone’s minds-.

What’s the difference between old fiberglass fly rods and new fiberglass fly rods?

Old Fiberglass Rods Vs New Fiberglass Rods: Do Blanks Matter?

If the glass in the new age rods is different, chances are you won’t be able to tell. The modulus may be a bit higher- meaning more stiffness in the rod and less weight- and based on what we felt when trialing old and new glass, this could account for the smoother feel.

So if most newer blanks can achieve a higher modulus versus old glass rods- What does that actually mean? Welcome to the great e-glass versus s-glass debate-

What you need to Know about "Modulus" and Fiberglass Rods 

First let’s go to Gary Loomis - one of the world's foremost authorities on rod design and founder of the G.Loomis Corporation, in an interview from 2009, Loomis broke it down like this: 

"What an angler needs to understand is how the word ‘modulus’ pertains to- rods. Modulus is not a thread count, as many would have you believe. Modulus basically equates to stiffness." 

"The higher the modulus, the stiffer the material is by weight, meaning less material is needed to achieve the same stiffness of lower-modulus materials. This results in a lighter product-"

And when it comes to new fiberglass rods versus old fiberglass fly rods, it’s all about that modulus number because it effectively amounts to overall weight, something we noticed in trialing the 70’s versus the Teen rods.

Modulus info for Glass Geeks: Old Fly Rods versus New Fly Rods

Older glass rods were usually built with e-glass (electrical fiberglass) with a rough modulus of 80 GPa with a density of 2.55 g/cm³- compare that to the new S-glass rods (currently advertised as "fast-action glass" or unilateral/unidirectional glass") with a rough modulus at 89 GPa and a density of 2.49 g/cm³.

What’s that mean? It means newer S-glass rods are less dense (read: lighter) with a higher modulus of elasticity (read: stiffer).

So if the raw material for the newer rods is both a) lighter, and b) stiffer- that means you can get the same "action" in the rod WHILE achieving an overall lighter blank. S-glass is being used regularly in fly rod construction this will definitely be a difference over (most) older glass rods that use e-glass construction.

What else makes new glass lighter- and faster? The components parts are also different on newer fiberglass fly rods.

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Component Parts of New Glass Rods Compared to Old Glass Rods

The componentry of new-age glass rods in comparison with older models of fiberglass rods is one of those differences.

If you check out the weight on new rod guides- besides having glass spey options, there’s a new era in stripping guides, snake guides, reel seats, ferrules- almost every piece that comes on to a fly rod AFTER the glass is ALSO lighter and more advanced than those pieces on rods from the 70’s- that doesn’t mean those rods are obsolete, it just means the level of technology available to fiberglass rod manufacturer’s now has become much more advanced.

Grip & Handle Evolution in New Fiberglass Fly Rods

Another noticeable difference between 70’s fiberglass rods and new fiber glass? Definitely in the grip game.

In most of the old model fly rods we trialed, it felt like the handles were almost upside down compared to today's fly rods. This might have to do with might have to do with market preference- but it’s probably because the cork quality and manufacturing techniques have advanced quite a bit since the 70’s.

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The taper shape on new rods is much more pronounced making for a lighter and better fit in the hand compared to the bigger, heavier cork in the older model of fiberglass fly rods we tested.

So that’s all good- but how does new glass compare with casting when set up against the older fiberglass fly rods of your dad’s age?

Differences in Old Fiberglass Rods & New Fiberglass Rods: Action

If you watch the video below, you’ll see what Cameron from the Fiberglass Manifesto has to say about older fly rods versus new fiberglass rods. It’s basically this there are phenomenal glass rods available from the 70’s- but one drawback to buying and USING old glass rods is that if you break them- chances are you aren’t going to be able to replace the piece you broke since they are most likely out of production.

You can listen to the entire interview on our Soundcloud profile here, or download it from iTunes right here

Now if you buy a NEW glass rod for the same price, you’ll probably be able to replace it or at least the pieces you break- so there’s that, but it doesn’t really answer what that action FEELS like check out the video below for some in depth break downs on the differences in old glass action versus new glass action and what both rods actually feel like


Fiberglass Rods Old & New: Philosophy & Return

Now who started the resurgence in fiberglass, why are they back- those questions are up for debate and if you have any ideas, feel free to throw them out here in the comments- we will enter the fray that ensues and reach out to industry experts if it comes to it.

A great place to get your feet wet with all things fiberglass fly rods (even anecdotal and philosophical matters) would be here, at Cameron’s Fiberglass Manifesto.

Interested in glass fly rods?

We’ve got fiberglass spey rods and single hand options available to purchase right here-. They even ship free. There’s no time like the present to go for glass

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#AskNorth40 is our weekly show where customers bring us their toughest questions, and we go find the answer from experts in the field here in the Northwest. Why do you feed flax seed to horses? If you learn your frost lines, can you grow more food? Where can we fly fish in the dead of winter? If you’ve got a question, use any social media platform and ask us with #asknorth40—we’ll be putting a new one out every week, so keep the questions coming. Click the #AskNorth40 name in this profile for a list of our latest episodes!

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