Bicycle Mechanics - wheel building question...

i just finished lacing up a wheel and i'm having some issues taking out the spoke slack. i'm trying to tighten the nipples but they're only threded on a 1/4 of the way and they wont thred anymore, the spokes are just starting to twist.

how can i correct this promblem?

i'm also going to add that in closer inspection it looks like there maybe some blueish/greyish gunk on the remaning 3/4 of threads.

could this be the issue?

Are you sure that you have the right nipples? Is it possible you have 15 gauge nipples and 14 gauge spokes?

Are you sure that you have the right nipples? Is it possible you have 15 gauge nipples and 14 gauge spokes?I was thinking the exact same thing.....
The nipples should turn easily with your fingers on loose spokes.

Are these used nipples? sounds like someone sprayed something on a rim with the nipples mounted on short spokes

brand new spokes and nipples ordered together from Ben's Cycles as a set.

brand new spokes and nipples ordered together from Ben's Cycles as a set.Were you able to screw the nipples onto the spokes before assembly just to make sure?

nope, they wouldn't thread more than a quarter of the way.

http://farm1.static.flickr.com/191/509672478_0aac21aabd.jpg

here is a picture of one of the threads, i can't get it past where you see it. when i try to thread it more, the spokes start to twist

You should take this up with whoever sold you the spokes.

The blue-grey stuff is spokeprep, which any good retailer would put on your spokes prior to giving them to you. I have no idea about the nipple thread issue.

here is a picture of one of the threads, i can't get it past where you see it. when i try to thread it more, the spokes start to twistDefinitely sounds like you got 15ga nipples with 14ga spokes. The SpokePrep or Loctite will prevent the nipples from rattling loose, but they don't bind so much that you end up twisting the spokes when trying to roll the nipples over.

As a test, take out one of the spokes and scrub off the SpokePrep with a 3M Scotch-Brite pad (kitchen-sponge with green scrubber). Then try threading the nipple on again. Will at least rule out or confirm that the SpokePrep stuff is causing you the problems. Or you can also try threading those nipples on some spare 14ga spokes with clean threads.