How do you find the optimum location of the first stripping guide on a fly rod?

The first, or butt guide, on a fly rod is the stripping guide. If you'll locate it about 31 to 32 inches from the butt of the rod, you'll be just about right for nearly any fly rod, length, line-weight, etc.

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Tom,
With a Spey or switch rod, would you measure from the end of the reel seat, or the butt end of the rear grip?

End of the reel seat. Everything has to be done in relation to the fighting hand and reel location. So let me rephrase that to read, about 31 to 32 inches from the butt of the reel seat.

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Tom,
By fixing the length to a specific number you aren't taking into account the length of the users arms.

I agree. If the stripping guide is too close to the reel seat, you are limited in the amount of line that can be "stripped" in. If it is too far away from the reel seat, (toward the tip), the user has to bend and, stretch and reach for the line. For me personally on my own rods, I put the stripper guide where the line is an easy full arms length reach with the reel seat located at my hip. Works for me without tiring after bending/reaching all day or getting short changed on the amount of line I can strip in.

That fixed number is based on years of taking into account the user's arm length. In nearly all cases, unless we're talking abnormally short or unusually long, you'll find that amount suits just about everybody.

In the book I did for Amato I penned the concept of holding the rod with a 90 degree bend in your elbow and then reaching out with your other hand and seeing about where it touched the blank without stretching or doing anything unnatural. The thing is, for most people this ends up being about 31 to 34 inches.

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Place the stripper guide at 29% of the distance from the reel to the rod tip.
This takes into acount shorter rods (6 foot) and two hand or switch rods where extra length is taken behind the reel seat.
Same number results proportianate wiht usable rod length.
31 to 32 assumes the rod is a 9 foot single handed more or less standard length rod.

No, that number will be correct no matter what the rod length. The criteria involved in setting the first, the stripping or butt guide, does not change with rod length. That distance and what takes place there is unaffected by the overall length of the rod beyond that point.

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