Technology of Rod Construction

High Performance RodsMade in the USA, Furnace Bay Rods believes in the phrase "made in the USA" and that is why from start to finish, everything about Furnace Bay Rods (other than quality components from Fuji) is American-made. We also build our rods to order. We do not warehouse except for a few often ordered models. So you can be assured that your rod is basically custom and has been built to our exacting standards.

Rod Terminology Refresher
The "Power" of a rod blank is the amount of pressure it takes to flex or "load" a rod. The "Action" relates to where the rod flexes along the blank when loaded. For instance, if a rod flexes close to the tip when loaded the faster it will recover after loading. So if you have a rod that has a "Light Power" and a "Moderate Fast Tip" the rod will not take much pressure to load, and about 40% the tip will flex with a moderate recovery time.

"Furnace Bay Rods are extremely lightweight and incredibly sensitive, without giving up strength. These are the best rods on the planet! Period."
Brien Witham - Pro-Staff

Rod Design
The buzzword for rod making today is "Modulus" which is just a term for the shear strain testing of the graphite fibers used. Most consumers believe that the higher the modulus rating in a rod the higher the quality must be. Yes the higher modulus fibers help to add certain positive performance qualities to a blank. Qualities like quick recovery time, crisp actions that cast well with more precision and less effort. But, the higher modulus rating comes with a price. The blank will be very brittle and prone to failure.

A more important factor, and ignored feature of modern graphite fabric is the "Strain-Rate". This is just a term that relates to the amount of stretch a fiber can take before it breaks. High modulus graphite fibers have a low strain-rate and are prone to failure where most Intermediate fibers have a high-strain rating. This creates a problem for rod makers. How to design a rod that has a light physical weight, high modulus, and a high strain-rate. The answer is engineering and design. We have engineered a rod design that uses a mixture of graphite materials and resins, placed just right in a pattern that enhances all the good qualities desired, plus smooth taper transitions for the durability and performance required by the pros and the weekend angler.

Effective Spine
Every fishing rod blank that is manufactured by rolling material around a mandrel will have a hard side (or stiff side). This hard side is call the spine (or spline). There are forces generated during manufacturing that cause this hard side to drift throughout the length of the blank such as epoxy resin curing, material wraps in any given place, and of course the consistency of the material being applied.

To assemble a balanced rod one must find what is called the"Effective Spine". This is the average of all those forces that are creating the hardness on one side of the blank. In other words there will be a line from butt to tip that will be "stiffer" than the rest of the blank and this area will resist bending more than the rest of the blank. We identify the "spine" in our blanks by using a Spine Finder, a piece of equipment that has raceway roller bearings in a 10" tube that is set at a 45 degree angle. The blank is place inside this tube and down pressure is applied to the tip of the blank sufficient enough to mimic the weight needed to load the blank as in a cast or fighting a fish. The spine will roll to the top every time this is done. We then mark the blank for assembly.

Placing the spine in the top position when you assemble a rod is very important to it's performance. For example: when building a casting rod you want the guides to be place on the same side as the spine. Why, because the blank (spine) will always roll or torque away from the load. In fishing rods the load is always "down", so if you put casting guides opposite the spine, every time you cast, set the hook, or fight a fish the rod will want to turn in your hand and roll to the top. This makes for a very uncomfortable day. Have you ever had a rod that would cast to one side or the other no matter where you aimed? Well if the spine is off when you load the rod to cast it will torque to one side or the other every time you load the cast.

Now on the other hand, a spinning rod's guides need to be placed opposite the spine. Spinning guides are on the bottom of the blank or towards the load. So if you put the guides on the spine side, which would put the spine down, every time you worked the rod the spine would torque away from the load, or up.

To summarize, the spine must always be place on top away from the load. Unless of-course you cast backwards over your head and fight the fish upside down????

Power Rating
Furnace Bay Bass and Inshore rods are given a power rating based on an industry standard incorporated years ago. The standard is basically the amount of force needed to bend a certain rod to its’ full flex point held at a 45% angle. To make it simple this is done by placing the blank locked at a 45% angle and then certain amounts of weight are applied to the tip until the blank flexes to the theoretical full bend.

Once this test is performed a rating is applied to the blank that correlates to a line class. This means that a power rated rod should flex under strain using the lowest line weight in that class without breaking the line. The upper end of the weight scale is an estimated line weight that the rod can handle without the blank breaking.

The rod can be used outside of the line class ratings but it will not perform as well or load properly outside of those parameters. This means, yes you can use 6lb test for a rod rated for 8lb test, but you are now below the line class rating and a hard hook set can break that line as well as not flex easy enough to fight the fish properly and you could break off. At the high end of the line class it is possible to use heavier line but the warning should be that you can overstress the breaking point and blank will break before the line will under severe flex. Like anything else these are guidelines to assist you in making the proper decision when choosing a rod to the specific technique you will be using. If a manufacturer finds out you are using heavier line than recommended they will void your warranty. But, most rod designers build in a little cushion for those who like super lines. Just be careful and keep track of the amount of strain you are putting on the blank.

Modulus Terms

Modulus- A measure of applied load (stress) that it takes to deform a material in its finished process state.

Flexural Modulus- measurement of elasticity, or flex under stress, of a certain fiber used in the manufacture of a part. (i.e., Carbon, Graphite, Glass, Boron, Aramid, etc.)

Tensile Modulus- measurement of shear strength or stiffness of a part which is made from fiber, relates to stiffness of a part made from that fiber. As modulus increases, stiffness increases.

Modulus is most commonly used in the terms to describe the performance properties of prepreg tape made from fiber such as carbon, or graphite, but does not relate to the actual performance design of the blank pattern.

Prepreg Tape- tape roll of fibers woven, weave, or layered. Then impregnated and coated with resin. Rod Patterns are cut from prepreg and rolled onto a mandrel to form the shape and taper of the rod blank.

 

Furnace Bay Rods Competition Rods

Using upgrades in Graphite / Carbon composite and (new to the fishing industry) epoxy resin lay-up we have improved strength to weight ratios for greater performance and stability. Our blanks have a Carbon scrim (sheet film) for control of the main fiber orientation and will add additional stability and "hoop strength".

Graphite Strand Modulus - 58 MSI
Carbon Fiber Strain rate - 41 MSI (Toray)