Anthony King posted: "The is the first time I've built one of these. I'm curious to hear the typical spoke tension used to build these up."
I'm guessing that the rims in question are the Fiamme Yellow Label old-style lightweight tubular rims. When building a wheel with a classic lightweight rim like a Fiamme Yellow Label, it is important to remember that "in the day" rims were considered consumables. People who regularly rode the really light rims tended to buy them 10 at a time, at pretty low prices. Tying and soldering spokes was more to facilitate a fast rim change than to increase the strength of the wheel. With hex head nipples, a Yankee drill and some practice, a rim drop was a quick job.
Thus, if I were presented with a NOS Yellow Label rim today, I would recommend that the wheels be built for show only, with a spoke tension just slightly tighter than wobbly loose, say in the 40 Kgf range.
If the customer insisted that these are rider wheels, then I would agree with Howard Darr, that even tension is significantly more inportant than cosmetic true and round. I would go to about 60 Kgf per spoke. I would also re-space the rear hub to one cog less than usual (4 cogs on a 120 mm hub or 5 on a 126 mm hub) to provide more balanced tension on the rear wheel. Note that you can take the outside cog off most Regina 5-speed freewheels to make a 4. As further protection for the rims, I would use the largest tubulars available. Remember that a lot of riders of tubulars in this vintage swore by the Campionatto del Mondo, which was an honest 29 mm width.
Good luck!
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