Once upon a time, I was presented with two fire extinguisher service providers.
The first one said:
Each fire extinguisher must be mounted exactly so many inches high, so many inches to the right of this door, and so many inches left of this door, must be
visible from so many feet in this direction, that direction, and that direction, must have a sign appended directly above that must also be placed this many inches high, must be charged at all time to so many psi, must be tested every so often, and replaced every so often regardless of whether they had been used or not - or tested fine....and on and on and on...
The second said:
I recommend two for this room, one for that one, and that utility vehicle you have, have you thought about one for that vehicle considering it's a work vehicle containing chemicals, tool, material hazards for your driver in the event of an incident? Oh, and a flourescent sign in each room indicating the general vicinity of the extinguishers is recommended. I'll come by every month
and check on them for you...
Guest who got the job?
Now before you folks go firing off all barrels of your shotguns at me in a knee
jerk reaction - consider the fact that I'm a wheelsmith with 2000+ wheels of experience going all the way back to 1984.
There's a difference between attention to detail in putting out honest quality work AND being downright anal and unmarried.
Seriously, just true and tension the damn things to the point where the loosest
spoke meets the minimal tension YOU the builder think necessary - and you have +/- .002 in. tolerance.
If you can't achieve the above within 2 hours build time on a rear wheel - toss
the rim as you probably have a defective joint or weak spot that a drunk on the
job allowed to pass through QA.
Don't get me wrong, I do enjoy most of the discussions that take place here on CR - but I do find that some folks do seem to take things a little too far.
Remember you are restoring a bicycle to give it some more life for yourself and
others who will appreciate it for hopefully another 10, 20, 30 years....
...but it's not going to last forever....you are not GOD...
Don't fight the same battle those trying to preserve the original copy of the Constitution of the United State of America are fighting....they are loosing.
Instead do both - give one some more life as is feasible as possible - but also
reproduce.
My Zeus won't last forever - I accept that - which is why I don't loose sleep over the fact that it has its last pair of brake hoods. Nor do I loose sleep over the fact that the front wheel has one loose spoke due to a slight weak spot in the Rigida SX100
But should I become a multi-millionaire - I wouldn't mind making my own reproductions...I don't take offense to quality reproductions.
My feet are on terra firma.
Bob Shackelford San Jose, CA USA
Quoting Jerome & Elizabeth Moos <jerrymoos@sbcglobal.net>:
> Well, I don't pretend to be an expert, but I been building wheels for about
> 25 years and in the last 10 years, I don't think I've had a wheel built by
> anyone else. I think Earle is exactly right that even spoke tension is
> the key to a good wheel. And the key to that, as he says, is to get the
> wheel in approximate true and round while spoke tension is still low, and i
> ncrease tension on all spokes in the same small steps.
>
> This, I think, is why it is so much more difficult to get a used wheel in t
> rue and round than a new one. A well used wheel will usually have widely
> varying spoke tension, even if that was not the case when it was new, and
> so it is much more difficult to get it true without overtensioning some spo
> kes. Lately, I've trued up a number of old wheels and wound up rounding
> off spokes or pulling rim eyelet loose trying to true these wheels. I've
> now concluded that, whereas I usually try to tension new front wheels and
> drive side rear to about 100 kg average, this is not practical on old wheel
> s without getting some spoke too tight. So I've begun to settle for 80 o
> r 85 kg average tension on old wheels. One thing I might try in future i
> s to completely detension old wheels, then retension slowly following the s
> teps Earle describes. I've rarely done this just because it takes more t
> ime, but it might be this would actually be faster than fighting to tru
> e
> an old rim, and certainly faster than replacing rounded off nipples or b
> roken spokes resulting from overtensioning. Of course, on used wheel
> s the rims have often deformed at least to some extent, so one is probably
> seldom going to be able to achieve the some average tension as on a new whe
> el without overtensioning some spokes.
>
> By the way, anyone know if the new owners of Wheelsmith offer the service o
> f recalibrating old Wheelsmith tension meters like the original company did
> ? I'd probably send mine in if this were available at a resonable cost,
> although it isn't all that critical, since as Earle says even tension is mo
> re important than maximum tension. So the Park tension meter, while, as
> Earle mentions, not highly accurate, is quite adequate for most wheels, sin
> ce it is the tension of the spoke relative to each other, not the exact abs
> olute tension of any spoke, that is of prime importance.
>
> Regards,
>
> Jerry Moos
> Big Spring, Texas, USA
>
>
>
> --- On Sun, 9/28/08, Earle Young <earle.young@tds.net> wrote:
>
> From: Earle Young <earle.young@tds.net>
> Subject: [CR]Building wheels.
> To: classicrendezvous@bikelist.org
> Date: Sunday, September 28, 2008, 9:35 AM
>
> Hi all,
>
> I'm a little late coming to this thread, but having been invited to
> weigh in, I'm gonna throw out a long post here. Skip it if you want, or
> see it live at Cirque 2009.
>
> I want to first say that from everything I've read and learned by
> experience, evenness of spoke tension is the most important parameter in
> wheel building.
>
> Let me explain why. Jobst Brandt posited that the overall strength of a
> wheel is directly proportional to the aggregate tension on the spokes.
> Park Tool and Barnett's Bicycle Institute both say that production
> wheels are acceptable with spoke tension that is plus or minus 20
> percent of the average. Ric Hjertberg, founder of Wheelsmith, warns that
> over-tensioned wheels are at least as fragile as under-tensioned wheels.
> One of the failures is cracking at the spoke holes in the rim,
> suggesting that there is an absolute maximum tension for any spoke.
>
> So, when a wheel has its tightest spokes at the maximum allowable for
> the rim, and the tension is at plus or minus 20 percent of average, then
> the average is going to be at roughly 80 percent of maximum. If one
> keeps the maximum tension at the same number, as one reduces the
> variation among the individual spokes, then the average tension becomes
> higher, and the aggregate tension along with it. By reducing the maximum
> variation in spoke tension to less than 10 percent, the increase in the
> strength of the wheel is about 20 percent (90 percent of maximum tension
> vs. 80 percent of maximum tension). If anybody has an issue with this
> logic, I would be glad to hear it. But if you want to dispute it, please
> do so with some numbers.
>
> Here's a primer on how I get there:
>
> Once I have spokes laced into the hub, but still rim-rattling loose, I
> correct the bend at the elbow so that each spoke is forced into pointing
> directly at its spoke hole in the rim.
>
> Then, I snug up the spoke tension just enough to stop the rim rattling.
> At this point, I will set the truing stand so that the side to side
> pointers are 4 to 6 mm wider than the rim, and add tension to the wheel
> by chasing the high spots. My goal is that when I am at 60 percent or so
> of final spoke tension, the wheel is within a millimeter of being
> perfectly round, and well within the side to side pointers. I try not to
> tighten any spoke more than half a turn at a time, and as I get closer
> to round, I may go around the wheel and add some tension to every spoke.
> During the process, I use a dishing tool to make sure I'm within my
> plus/minus 2mm tolerance of centered on the hub.
>
> At that point, I will use a tensiometer to tighten each spoke to exactly
> the same tension, or actually as close as a Park TM-1 will allow. I do
> this without regard to roundness or trueness, just as a gauge of how
> well the rim was made. At the end of this process, spoke tension will be
> 75 to 80 percent of final value.
>
> I then move the side to side pointers to about 1.5 mm from the rim on
> each side, correct the side to side trueness and then check and re-check
> the dish until I have a reference point that is within 0.2 mm or so of
> exactly centered.
>
> I then turn my concentration again to the roundness of the wheel. I use
> the tensiometer to balance relative tension with the relative
> out-of-roundness. I sortof use the rule that the percentage difference
> in spoke tension should be about 20 times the percentage of
> out-of-round. On a 700 C wheel, 0.1 percent out of round is about one
> third of a mm, and I try to achieve this with a tension differential in
> the range of 2 percent. Every rim has some manufactured imperfections,
> so not every irregularity in roundness will be correctable within this
> ideal, and some modern rims are better judged by the machined-in wear
> line than the outer edge of the rim itself. That becomes a balancing act
> between cosmetic imperfection of round and true and evenness of tension.
>
>
> In reality, if the final product varies by plus or minus a millimeter
> side-to-side and radially, the imperfections will be imperceptable when
> you ride.
>
> I hope this helps those novices out there build better wheels. I believe
> that properly chosen handbuilt wheels are nearly as important as frame
> fit in determining overall ride satisfaction on a bicycle. Thanks for
> reading this far.
>
> Earle Young,
> Madison, Wisc.
> Offering expert wheelbuilding service for classic and modern bikes.
> http://www.earleyoung.com
>
>
> _______________________________________________
>
>
> _______________________________________________
>
>
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