Bicycle Mechanics - Need help on spoke legnth info needed for my wheelset build-up.

First of all, I found out that wheel buidling services from my LBS isn't that cheap if I have them do the whole thing, so I will be lacing up my own wheels as I had done back in college to cut down on some labor costs. Used to let my LBS figure out spoke legnth to lace up my own wheels back in college. They don't seem to be as sympathetic about giving me a free spoke legnth calculation as I am way past my poor college kid days..I guess. I would also like to use the information to shop around in the net for spokes if I have to.
Tried to figure out how to use the spoke calculator found on-line but ended up being totally confused by the Excel spreadsheet and I'm afraid I'll just end up getting the wrong legnths.
The hubs I will be using are 32H Mavic 500 front and 550 rear hubs, with the standard 100mm spacing for the front and the 80's standard 126mm spacing for the rear.
The rims I will be using are 32H Mavic G.E.L. 280s tubular rims. Planning to use 14/15/14 DB SS spokes from DT.
What spoke legnths do I need for the front and rear wheels? Are there any requirements for washers at the eyelets/nipples which I seem to hear about some certain rims?
Any other advice on my wheelset build-up will be appreciated.

Thank you,

Chombi
84 Peugeot PSV
85(?) Vitus Plus carbone 7

Have you tried using the DT Swiss on-line spoke calculator?

GEL 280

700c R = 615 mm

Mavic 500 Front

r = 40
c = 28

SL = 300.72 mm


Mavic 550 Rear

r = 45
c = 37
c = 19

SL = 300.89 mm
SL = 299.21 mm


=8-)

I assume you're doing three cross:

Front 300.4mm
Rear left 300.8mm
Rear right 299.0mm

Looks like my numbers match with Mr. Rabbit's. Spoke head washers are only needed if there is a large difference between the spoke hole diameter and spoke diameter at the head (check for play). Good luck with the build.

GEL 280

700c R = 615 mm

Mavic 500 Front

r = 40
c = 28

SL = 300.72 mm


Mavic 550 Rear

r = 45
c = 37
c = 19

SL = 300.89 mm
SL = 299.21 mm


=8-)

Thank you very much mrrabbit!!

Chombi
84 Peugeot PSV
85(?) Vitus Plus Carbone 7

Your'e welcome. Be sure the nipples allow 1mm of spoke past the top...gives you a little 911 overhead...otherwise you'll be okay with 301's and 299's from DT. No washers needed...

=8-)

I assume you're doing three cross:

Front 300.4mm
Rear left 300.8mm
Rear right 299.0mm

Looks like my numbers match with Mr. Rabbit's. Spoke head washers are only needed if there is a large difference between the spoke hole diameter and spoke diameter at the head (check for play). Good luck with the build.

Yes Yan, I forgot to mention that. Three cross.
Looks like I got some solid numbers to work with from you guys!
Thank you!

I'll post up pics of the resulting wheelset once I get them done!

Chombi

Here's the easiest calculator I've seen. Quite accurate by all accounts:

http://lenni.info/edd/