Spoke Length

[Hopping]

Ok guys, i have a problem, im at work, and have to build up a wheel for a guy (workin at a bike shop obviously) but we have a Alex Supra V rim (36h) and a Rear XT Disc (36h) hub. what spoke length do i need? we have built it up 5 times now! and we cant get it laced properly, ive build tuns of wheels so its not like im a rookie at this, but we cant get this spoke length figured out. has anyone got an idea?
thanks guys

Ryan

[kidwoo]

Are you making the hub and rim measurements yourself or going from charts?

AND

What calculator are you using?

[Repack]

Google search "spoke calculator". You'll get some nice Excel doc's with all the equations figured into it. Did you measure the ERD yourself or trust a source? A lot of the spoke/rim databases that I have seen have a lot of mistakes. I only trust my own measurements or factory measurements.

[boxxerace]

And.... Are you sure you are making the proper calculations for the cross pattern you are doing?

For exam: ( I know Im preaching to the choir- but just the same ) a 2 cross or radial pattern will need shorter spokes, a three or 4 cross will need much longer spokes.

In addition, make sure to add or deduct for the wheels offset including hubs that have disc brakes, and all ( except maybe Ritchey 0-degree hubs ) rear hubs.

Also, if you call up quality or Bti, they should have a calculator that you can get made for wheelsmith or Dt spokes. It has the same functions, but comes with a helpfull book explaining different setups.

And lets hope your not trying to lace a 32 hole hub to a 36 hole rim... :D grin.....

Good luck.