Eyelet Science

[Slayer]

Does anyone know any of the science behind eyelet spacing and sizing? I'm building a $15 2pc 9ft 5wt and some spacing/sizing charts have the position of the first stripping guide almost 4 in. different than others (all with 10 guides 2pc). Some have the last guide before the tip top a size 1/0 and others a 1,2,or 3.
Does it make that much difference?

Why would some one use 8 guides vs. 9 or 10?

What would the difference in distance and accuracy be with sizes say:
1-1-1-1-1-1-3-3-4-12
vs.
1-1-1-2-2-2-3-3-8-12
vs.
2-2-2-3-3-3-4-4-8-12

If you use one of those oversized tip tops does this decrease accuracy?

P.S. I'm not looking for the "that's part of the fun, build it how you want" answers like I got 2 rods ago. I'm looking for the how and why's of spacing and sizing.

Thanks

[Norm]

accuracy has any thing to do with it in my opinion. I think the size of the guides has more to do with the asthetics of the rod. You don't want big bulky guides on a small, slender lightweigth rod. I put #1/0 on the first 3 guide spots from the tip then go to #1's then #2's then a #3 with a #10 agate stripping guide.

Norm

[Cary]

This is from my RB Outline, not quite a scientific paper, but maybe you can use some of this:

GUIDE PLACEMENT
A custom-built rod should have the guides placed at intervals determined by the flex of the blank. This is determined by conducting a stress distribution test. Most custom rod builders are in agreement that spacing charts provided by manufacturers should not be solely relied upon. However, several rules-of-thumb are needed to at least determine a starting point:
· Use spacing charts, and ignore above
· Start first guide 4 to 4.5 inches from tip
· Number of guides = Length in feet +1
· Stripper guide placed 28 – 32 inches from butt cap (less for folks with short arms, greater if casting distance is key objective).
· Place guides at a consistently changing rate along blank, i.e., add .75 of an inch for each guide interval.

To perform a stress distribution test, use masking tape to secure the guides to the blank. Tape or temporarily wrap the female end of the ferrule to keep from splitting the blank! Now, string up the rod using a highly visible string. A flyline wil do fine. Have a friend hold the blank at a 45 angle, and pull the string towards the butt, putting a deep flex (don’t over do it) in the rod. Note the angle of the string as it leaves each guide. Also note the distance between the blank and the string. The object is to even out the curve, and avoid abrupt changes in either, by moving the guides, or adding/ subtracting guides.
It’s a good idea to test cast before you wind the guides. What your looking for is any line slap that occurs during the cast. Line slap is when the line hits the blank when casting or shooting line, and can be eliminated by adjusting the guide spacing. Line slap will kill distance. I’ve found that with proper stress distribution spacing, line slap is quite rare.

[cheech]

Slayer- Just so you know, Cary and Norm are the rod building masters. Chris is probably in that category too. Cary should publish that last post:) What more do you need after that?

[Cary]

Cheech, your too much.

And don't forget, Slayer, I bought my last rod from Cheech.... Which, BTW, casts fine!

[chris]

Each blank, regardless of maker or material is unique. There is no exact science unless you get a lab going and start testing every blank over and over and over and over. I have found that the tip should always have a guide within 4" of the tip on 4 wt or smaller and just over 4.5" on 5 or larger but never made it to the next guide when it came to pure vintage analysis of numbers. The butt is less strategic unless you start measuring with specific reels in place and logging your data (much like a spot count) being that the line comes off different reels at different depth and speed but that is something most would not worry about. Torque and friction come into play with the length of the lever in each human body's hand and arm. The movement whether it be stiff in function or limber in ability.......

I try to keep the classes as basic as possible and have been impressed at the levels Walks, Slayer, Jason and others have taken this hobby. Build on boys, hopefully I did not confuse anyone.

Cheech, Masters we'll never become. We will only toil on the legacy others have built generations ago.

[Slayer]

Hey thanks for your input. Ya'll are great.