Be patient. I just ordered a set of spokes today for my first wheel build. I'm reusing an old Miche front hub to be laced to a Sun CR-18 rim.

This much I can say: I've taken measurements for everything instead of relying on anything anybody says and when I plug the SAME numbers into the three spoke calculating websites that I know of,

http://www.wheelpro.co.uk/spokecalc/ ,

http://www.bikeschool.com/tools/spoke-length-calculator and

http://lenni.info/edd/ , I find that the difference between the shortest and longest calculated spoke length is about .3mm.

It's when I read the measurement instructions at these three websites that I can see where things can go awry.

It's not just the definition of ERD that can be different. It's also the definition of the measurement from the center of the hub to each flange. How should you factor in the width of the flange?

The only reason flange thickness doesn't appear as critical as is how to "properly" measure ERD is that it changes the spoke lengths that I've calculated get by only about .2mm at most.

One thing that I have done is to use a digital micrometer to measure the depth from the top of the nipple to the bottom of the driver slot. Turns out that the two nipples that I used for measuring ERD have two different depths. When added together I get about 2.8mm.

Now what I've done for myself is to take an ERD measurement based on using the bottom of the driver slot and use that to calculate the LOWER limit for spoke length and round UP to the nearest integer above.

I then add 2.8 to my measured ERD, run the numbers through for an UPPER limit and to see if this integer millimeter length that I've chosen is less than that and become confident that I didn't f**k up.

Give me a week for the spokes to come in the mail and for my finding out if this will be the reality.