John B. wrote:
On Tue, 14 Mar 2017 10:51:45 -0400, Frank Krygowski
wrote:

https://janheine.wordpress.com

Today's blog post is about building strong wheels.

He seems to ignore the upper spokes. If the bottom spokes become
unloaded ( looser) then, logically, the top spokes must become more
highly loaded (tighter) :-)
--
Cheers,

John B.

It's a bit asymmetrical. If the rim was very "floppy", then only one spoke
at a time on the bottom would be detensioned, but a large number of upper
spokes would share the increase. As the rim gets stiffer and stiffer, then
the detensioning of the lower spokes gets more uniform and smaller. In the
ultimate case of a perfectly stiff rim, then the loss of tension in the
lower spikes would be perfectly and symmetrically compensated by an
increase in tension of the upper spokes. So you can leave less upward
margin in your spoke tension than you have to leave on the downward side.