datakoll wrote:
> Jim,
> "Effective Rim Diameter. This is the rim diameter measured at the
> nipple seats in the spoke holes, plus the thickness of the two nipple
> heads. The E.R.D. is needed for calculating the correct spoke
> length." - Sheldon Brown's Glossary - I assume Sheldon read thru his
> calc software.
> Not where Andrew Muzi leaves his spoke ends.
> Notice is this definition Sheldon, rarely incorrect, writes "is NEEDED
> for calculating THE CORRECT SPOKE LENGTH" not is the correct spoke
> length. Knee dead. NE sense of humor. Gotta measure the knee dead
> here or ura over the 1.5mm murphy error spectrum.
> You are fired dude! try the plumbing MO.
> we'll throw a rope down tomorrow morning.
I wasn't suggesting _everyone_ calc spokes as we do, only explaining why
we choose this format for wheelbuilding here.
Moreover, any length between seat of nipple (photo) and top of nipple
(Jobst's suggestion) is perfectly functional. There's no good reason to
anguish over a 2~3mm variance in spoke length within that range.
Others have exhaustively explained various rim ERD measurement methods.
In short, since you've built it and found your spokes 6mm* long, choose
a length 6mm* shorter than that and build it!
In the days before painlessly accessible computer spoke calc programs,
we used a wall chart**. That's an excellent method. Once having built a
wheel, one records the hub, rim, drill, F/R, cross and length. Even if
the length is not ideal (2mm long for example) one may can record the
ideal length for next time.
* or whatever it was
** We still have and use them. A chart is quicker than any program.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971