I've always heard (and practiced, due to limited availability) that rounding down by up to 2 mm is ok. So you could conceivably be able to get away with just the two lengths. 282 and 280. Brass nipples last longer. Be aware, when tightening the rear, to not overtighten the drive side too early on. It's an easy trap to fall into when in the early dishing stages. No need to use heavier spokes on the drive side. And be sure to lube the threads before lacing them. I use 30 wt motor oil.
Robbietunes has a good source for spokes and nipples online. I can't remember it off the top of my head.
Good luck and enjoy.
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Originally Posted by
Bah Humbug
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