Wheel building - how to tighten spokes to have perfectly equal tension

Question

So far I figured it out following recipe for perfectly adjusted front rim:

Assemble the wheel leaving tiny portion of thread visible outside nipple for every spoke.
Tighten each nipple equal number of 360 degree turns (e.g. 6 turns out of 12 total).
Keep adding equal number of 90 degree turns to each nipple until you get equal tension of about 100 kgf (1000 N) for every spoke (remove spoke tension)
True the wheel (remove spoke tension)
Adjust the spokes again until you get equal tension of about 100 kgf (1000 N) for every spoke (remove spoke tension)
Keep repeating step #4 and #5 until you get equal tension for every spoke while rim stay's true.

Problem is that step #6 has to be repeated too many times, is there a faster way or can you advice any better sequence for wheel building?

Michael · Accepted Answer

Don’t obsess over it. Perfect is the enemy of good enough.
Something like ±10% spoke tension deviation is perfectly fine. For lateral and radial truing about ±0.5mm is fine. With lower quality (or damaged) components it will be harder/impossible. On the front wheel you have more margin since it’s symmetrical, has less spoke tension and is less prone to broken spokes. On the rear wheel asymmetrical rims can help because then you need less tension on the drive side and can put more on the non-drive side. Again giving you more margin (and/or a stronger wheel).
Experience and a methodical approach will help you get there faster. For example when you find an area which is laterally out of true you shouldn’t only loosen or slacken one spoke but work on both sides (i.e. loose one side by half a turn, tighten the other by half a turn) and include the neighboring spokes as well. Be aware of spoke wind-up and account for it (easier with bladed spokes). Stress relieve early.
On my first wheel some nipples broke prematurely. I suspect that turning them countless times abraded and damaged them. Now I always use grease on the nipples (where they contact the rim) and try to get it done in as little turns as possible.

juhist · Answer

Wheel building is a repetitive process. You have to alternately work on spoke tension equality, stress relieving, centering (dish), lateral truing and radial truing. Any of these steps can affect the other steps. Usually wheel building works by making major adjustments to all of these, doing a separate round of smaller adjustments to all of these, then doing even smaller adjustments, etc.
However, there's one location where you can do a mistake. If you put too high tension on the spokes, it may be possible you can't laterally true the rim. It is possible that with too high spoke tension, a lateral correction somewhere can create an even larger error elsewhere. It is also possible that if you have too high spoke tensions, you may be able to true the rim but then after stress relieving it becomes untrue again.
Also if you have a low quality or damaged rim, it is possible you cannot achieve trueness and spoke tension equality at the same time. Then you have to compromise on some qualities. If you are compromising too much, then you may need to throw away the rim and replace it with a new better rim. This won't happen with new reasonable quality (and thus somewhat expensive) rims. It only happens with old damaged rim, or the very cheapest of rims.
I usually find that by about 4 hours, the wheel is good enough. It may be possible to fine tune it by spending 4 hours more (8 hours total) to build the wheel, but that usually doesn't pay off. You won't become magically any faster by having 0.1mm error in lateral trueness when compared to someone else who has 0.25mm error in lateral trueness -- unless you have misadjusted your brakes for no clearance.

Wheel building - how to tighten spokes to have perfectly equal tension

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