"Paul Boyd" <
[email protected]> wrote
[snip]
> So, has anyone taken the plunge and built a wheel that was a
> success first time round? Experienced wheel-builders seem to knock
> them out for a past-time (but unless you're doing it professionally
> why do you need to keep building wheels?), but I'd like to hear
> from people who might have just built one or two without any
> problems
[snip]
I must have built at least half a dozen, but, since that has been
spread out over 30 years or so, it's like being a novice each time.
Once I did it wrong, and found the spokes crossing over to obstruct
the valve hole. I swore a bit, and moved all the spokes round by one
spoke hole.
I'm slow too. I would starve if I had to do it professionally, and
didn't speed up. I've built wheels by reading instructions from a
book, and I've done it by copying a identical wheel.
It helps if you have spokes of *exactly* the right length, so that
you can see just a few turns of the threads when the spoke nipples
are tightened up. Rims and spokes are made amazingly precisely, so
the wheel will be pretty round if you see the same number of threads
sticking out of the spoke nipple (towards the hub - you don't want a
too long spoke that sticks out where the inner tube goes).
Professionals can probably get away with a spoke that is slightly too
long. You can file those too long ends off, but a too long spoke
won't show any threads, losing you the helpful short cut in truing.
There is, or at least was, a book, "Sutherland's Handbook for Cycle
Mechanics" which has tables of spoke lengths needed for different
makes of hub and rim. The book has got thicker, and more expensive,
over the years, but I imagine bike shops would have a copy, or some
equivalent.
Because spoke length matters less, I think, to professionals, some
bike shops will try to sell you the wrong length spoke, if they don't
have quite the right length in stock.
If you have to dish the wheel, as you will for a back wheel, then the
spokes on the two sides will be of slightly different lengths, not
enough to need to buy two kinds of spoke, but enough to get two
different numbers for your spoke thread counts.
If the rim is slightly out of round, as with a beat-up old rim, I
can't help you. Flat spots, from hitting something, such as landing
after a jump, are the usual problem. Some people, claim that they
can get the rim round again by tightening spokes appropriately, or by
beating on the rim with a rubber mallet (into a mould) but I usually
can't
When you have built the wheel, you have to true it. In fact there
are a lot more times you have to true a wheel than build one.
My theory is that a factory, machine built, wheel ought to be as good
as a hand built wheel, provided the factory wheel is hand trued after
being built. Cheap machine built wheels don't get de-stressed,
either at the factory, or in the bike shop, so you will likely need
to de-stress your wheel when you get your new bike, or new wheel,
home.
The reason for de-stressing is that when you screw a nipple onto a
spoke, screwing the nipple twists the spoke rather, winding the spoke
up like a spring. If you leave the spoke wound up, it will gradually
try to unwind itself, thereby unscrewing itself from the spoke
nipple, and messing up the trueness of the wheel, after some miles of
riding.
To de-stress a wheel you prop the wheel up between floor and wall, so
it is at 45 deg to the horizontal. You then lean on the rim where
the rim is furthest away from wall or floor. By leaning on the rim
you bend the rim slightly, enough for some spoke nipples to be loose
in their holes in the rim. The loose nipples let the wound up spokes
unwind themselves, which will make a sort of creaking noise as it
happens. To let more spokes de-stress, turn the wheel round by a few
degrees, and repeat the leaning. When you have gone all the way
round, and turned the wheel over and done it from the other side,
there should be no more creaking, which means the spokes will no
longer try to unwind themselves.
Actually, after you have de-stressed the wheel it will probably be
worth while to true the wheel again, to get it exactly right.
I will let somebody else talk about wheel truing
Jeremy Parker