Amazing! I was going to reply, but since I have only built up a few old rims I decided to refrain. What Steve suggested is exactly what I was going to send to the list :^)
Doug Van Cleve Chandler, AZ
On 7/31/05, Steve Maas <stevem@mail.nonlintec.com> wrote:
> The basic principle is that you want to make them as tight as possible sh
ort of warping the wheel or breaking something. Usually, the rim is the lim
iting factor. If it starts to warp--like a potato chip--it's too tight. Mos
t modern rims will easily handle 100 KGF, but older ones may not. The rims
on my Carlton (ultralight steel) warped at something considerably less than
100; I can't remember the exact value. So, in general, I make the front sp
okes 100 KGF if the rim can take it. The rear is more of a problem--often,
I find that 100 KGF on the right side means that the left must be down arou
nd 40 (I'm going from memory here, so the numbers may not be exactly right)
, which seems awfully low. I then make the right side 120, which puts the l
eft at about 50. I'm afraid to go much higher on the right, especially with
older rims, for fear that the spokes might pull out of the holes.
>
> You can check Brandt's book for the yield strength of the spokes. These n
umbers should be comfortably below the yield point for both 2.0 and 1.8 MM
spokes. I don't think you will reach the yield point without damaging the r
im, but fatigue--the REAL reason spokes break--is much worse near that poin
t.
>
> Whatever else you do, don't neglect to stress relieve the spokes!
>
> Finally, before anyone suggests it, making the tensions high makes the wh
eel stonger but NOT stiffer.
>
> Steve Maas
> Dublin, Ireland
>
>
>
>
> ---------- Original Message ----------------------------------
> From: Jerome & Elizabeth Moos <jerrymoos@sbcglobal.net>
> Date: Sun, 31 Jul 2005 12:56:43 -0700 (PDT)
>
> >Although I've built quite a few wheels over the years, I don't do it on
regular enough basis to remember all the details without consulting notes,
books, etc. One thing which seems to be conspicuously absent from most boo
ks and from the manuals of wheelbuilding equipment is the recommended spoke
tensions. This may be partly because of the many possible spoke gauges, s
hapes, materials and spoking patterns, but I suspect fear of liability may
play into it as well.
> >
> >Can anyone recommend tensions in Kg (that's the units on the conversion
chart with my new Park tensionmeter) for front wheels? Rear drive side? R
ear off side? I'm talking about classic wheels here. 2.0 or 1.8 or 2.0/1.
8 butted round spokes, DT if I am building new wheels. 700C or 27" alloy r
ims, sewup or clincher, 3 or 4 cross.
> >
> >Regards,
> >
> >Jerry Moos