Are there any building techinques or processes that will speed up the action of a blank? New to building and am just curious. I have read that by cutting down a blank from the butt end that it effectively slows the action some. Is that tru and if so is there something you can do to speed the action up?

Cutting the blank from either end will slow the action. Extending the blank from the butt will generally make the action faster.

Do make sure you are not confusing action (where the rod initially flexes) with speed (reaction and recovery time).

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thank for bringing this to my attention I was actually refering to the speed of recovery not to familiar with the use of rob building jargon yet.

James.
The unencumbered blank has a given recovery rate. Any weight added reduces that rate. So in order to preserve the most recovery keep the components as light as possible. Generally means no ceramics as runners. Use guides like REC Recoils.

Herb



Edited 1 time(s). Last edit at 08/15/2015 07:51AM by Herb Ladenheim.

James;
If you will take the time to click on the "Glossary" button above it will give the definitions of most rod building terms. Taking the time to read them will greatly increase your understanding of rod building jargon and substantial decrease your learning curve.

If you shorten the blank, you would likely increase the speed (reaction and recovery) but I'm not sure what that gains you against just buying a blank in the length you want to begin with. And if you're shortening it to a point less than what you need lengthwise for your type fishing and casting, then increasing the speed won't have been worth it.

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Herb Got it! I have a hard time using anything but Minima's for guides. Heavy ceramics just feel like they ruin the blank when built side by side.

Thanks - Marc

Keep it simple - that's all I can handle!

James,

Do you have a particular application in mind where you are trying to make a blank recover faster, or are you posing the question as a hypothetical?

In general, the recovery rate is inversely proportional to mass and length with mass added closer to the tip slowing the recovery more as the added mass gets closer to the tip. Similarly, as a rod gets longer, the center of mass moves farther from the fulcrum giving the rod more rotational inertia, making it harder to start and stop, thus leading to a slower recovery time.

The recovery rate for blanks with identical length, action, and power made from different materials will be directly proportional to the modulus of elasticity of the material, i.e. a high modulus blank will require less material to duplicate the action and power allowing for a lighter build and thus a faster recovery rate compared to lower modulus graphites and fiberglass.

If you want a measurement that corresponds to the recovery rate, you can measure the resonant frequency of the blank, but some care needs to be taken. As you increase the deflection of the tip, the frequency will go down, as a fishing rod is not an ideal system. If I remember correctly, the CCS system outlines a technique for measuring the frequency with a load used to simulate casting a fly line. This allows the builder to be able to tune a rod to an angler's preferred casting stroke, if desired.

In terms of action, action is often described in two ways. The first is where the rod first begins to flex. In this scenario, the action is determined by looking at a blank and determining at which percentage of its full length that it begins to flex. As you trim from the butt, the flex point does not change, but because the blank is shorter, it represents a greater percentage of the blank length, and thus a slower action. When you trim from the tip you are removing the most flexible portion of the blank, making it more difficult to load the blank. This will drive the initial flex point deeper into the blank thus slowing the action.

If you want to make the action of a rod faster, extend it from the butt. The initial flex point of the rod does not change, but as the rod gets longer, the distance to the flex point is a lower percentage of the total blank length and thus the action is faster.

The other description of action measures the angle of the tip with respect to horizontal when the blank is loaded by deflecting the tip a percentage of its length, as described by the Common Cents System (CCS), and in a different from with RDA as used by Point Blank. The greater the angle, the faster the blank.

Joe

Not planning on shortening a blank just trying to get a better understanding of the cause and affect of actions and component choices that i make when building. Thanks all for the information the gears are turning now.