I am about to replace the rear rim on one of my bikes and will transfer the old spokes and nipples straight across as others have suggested. Do I need to clean the threads on the old spokes and then put spoke prep on them, just dip in spoke prep, or not need to do anything? I know to put a drop of 3-in-1 where the nipples meet the eyelets. Thanks for any insight and advice you can provide.

I use anti seize on the threads, to facilitate maintenance truing.

I thought it was best to use something like spoke prep that keeps it from seizing, but also provides a bit of hold to keep it from loosening. I think I also read about using loctite 220 after the wheel is built because it seeps into the threads. Something about brass nipples not needing lubricating? I got this from wheel fanatyks web site. Just want to understand before starting so I do it right.

you should replace the spoke prep before the rebuild, just re-dip is only need.

If you have enough tension on the spokes they're not going to loosen, even when the spoke threads are properly lubricated with anti-seize, even with Campagnolo hubs that have a more than typical imbalance between drive and non-drive sides, even when you have 250 pounds of obese rider + luggage + bike rolling on your wheels.

Except when you bend the rim, although that generally implies replacement which fixes the problem.

As a foot note, "hard to turn" nipples don't necessarily imply sufficient tension.

Thanks for the replies. I don't know how much tension they should have, but will try and make them uniform and also good and tight. I only weigh 130 lbs. but use the bike to carry loads. The spokes are HUGE, maybe 12 gauge. Is there any method for calculating what the approximate tension should be? It's a 700C 36h Campy rim. I have a tension gauge, but on spokes this thick I don't know that it works.