Sleeved Vs. Welded Rim

In article <[email hidden]>,

Kenny said:

I'm considering getting new 700c rims. One pair of rims is welded
together while the other pair is sleeved together. They both weigh the
same per rim at about 410 grams. From the perspective of the consumer
which type of rim is better?

The one with more spokes.

--
Ryan Cousineau [email hidden] http://www.wiredcola.com/
"I don't want kids who are thinking about going into mathematics
to think that they have to take drugs to succeed." -Paul Erdos

Kenny who? said:

I'm considering getting new 700c rims. One pair of rims is welded
together while the other pair is sleeved together. They both weigh
the same per rim at about 410 grams. From the perspective of the
consumer which type of rim is better?

Consider much more important whether either of these rims has sockets
AND eyelets. non-aero (deep-V) rims without sockets load only the
outer wall of the rim and cause cracking. There are still rims with
sockets and eyelets that load both inner and outer rim walls with
spoke loads. Get one and forget about how the rim is joined. I've
ridden around 500,000 miles on unwelded rim joints without even a
slight "tick" at the joint when braking.

It was Mavic (Look) that sold the bicycling community on the need for
machined, welded, anodized and aero rims. Believe everything they say!

Jobst Brandt

Kenny said:

I'm considering getting new 700c rims. One pair of rims is welded
together while the other pair is sleeved together. They both weigh the
same per rim at about 410 grams. From the perspective of the consumer
which type of rim is better?

welded.

it has better fatigue properties [fwtw], usually has better weight
distribution, and produces a better brake surface.

jim beam said:

welded.

Quoted message said:

it has better fatigue properties [fwtw], usually has better weight
distribution, and produces a better brake surface.

Actually, the welding produces a worse brake surface, it's the
machining later on that produces a better brake surface. Which brings
us to the point about welded rims : I believe they are cheaper to
constuct than pinned rims, which is also a consumer advantage.

If you listen to jobst, then a pinned rim is better. But Jobst's main
failure mode on rims is sidewall wear-through, which comes from
descending like a manic. Imho this failure mode is a Jobst / California
thing.

In most parts of the country, where winters rule and the mountains
aren't so steep, potholes and flat rims are probably the main failure
mode. Welded rims work just fine in these areas.

- Don Gillies
San Diego, CA

On 31 May 2006 11:16:18 -0700, [email hidden] (Donald Gillies)

Quoted message said:

jim beam said:

welded.

Quoted message said:

it has better fatigue properties [fwtw], usually has better weight
distribution, and produces a better brake surface.

Actually, the welding produces a worse brake surface, it's the
machining later on that produces a better brake surface. Which brings
us to the point about welded rims : I believe they are cheaper to
constuct than pinned rims, which is also a consumer advantage.

If you listen to jobst, then a pinned rim is better. But Jobst's main
failure mode on rims is sidewall wear-through, which comes from
descending like a manic. Imho this failure mode is a Jobst / California
thing.

In most parts of the country, where winters rule and the mountains
aren't so steep, potholes and flat rims are probably the main failure
mode. Welded rims work just fine in these areas.

- Don Gillies
San Diego, CA

Dear Don,

I expect that either the pinned or the welded rim would work fine.

Kenny said:

One pair of rims is welded together while the other pair is sleeved
together. They both weigh the same per rim at about 410 grams.

If both rims actually weigh 410 grams, then the pinned rim is 410
grams of metal, less the minor weight of the pin--a little lighter and
thinner as a rim than the welded rim, which is still 410 grams of pure
rim after machining the brake surface.

The pin adds no strength, so the idea is that it's a bit like
comparing a pair of wrestlers who both weigh 410 pounds when one is
holding a bottle of pop.

(And the other wrestler, it could be argued, has starved himself down
and is weaker than he appears, like a machined brake surface.)

But I doubt that the difference is of any practical importance, just
as I doubt that both rims actually weigh 410 grams.

In my innocence, I used to believe that a 410 gram advertised weight
meant that the rims really did weigh that much.

But kindly folk on RBT patiently explained to me that aluminum rims
are extruded like toothpaste from a die and that the hole in the die
slowly wears--so the last rims in a production run may be 10% thicker
and heavier than the first rims.

Still, it's a fun theoretical question, which is often the point here.

Cheers,

Carl Fogel

In article <[email hidden]>,
[email hidden] says...

Quoted message said:

I'm considering getting new 700c rims. One pair of rims is welded
together while the other pair is sleeved together. They both weigh the
same per rim at about 410 grams. From the perspective of the consumer
which type of rim is better?

Same.
-----------
Alex

Donald Gillies said:

jim beam said:

welded.

Quoted message said:

it has better fatigue properties [fwtw], usually has better weight
distribution, and produces a better brake surface.

Actually, the welding produces a worse brake surface, it's the
machining later on that produces a better brake surface.

strictly speaking, that's true, but the point is, pinned rims are often
misaligned and that can lead to braking issues - welded rims don't have
that problem.

Quoted message said:

Which brings
us to the point about welded rims : I believe they are cheaper to
constuct than pinned rims,

untrue.

Quoted message said:

which is also a consumer advantage.

If you listen to jobst, then a pinned rim is better.

yeah, just like jobst says bike bearings are elasto-hydrodynamically
separated and that this protects them from brinelling...

Quoted message said:

But Jobst's main
failure mode on rims is sidewall wear-through, which comes from
descending like a manic. Imho this failure mode is a Jobst / California
thing.

In most parts of the country, where winters rule and the mountains
aren't so steep, potholes and flat rims are probably the main failure
mode. Welded rims work just fine in these areas.

- Don Gillies
San Diego, CA

In article
<[email hidden]>,

jim beam said:

Donald Gillies said:

jim beam said:

welded.

Quoted message said:

it has better fatigue properties [fwtw], usually has better weight
distribution, and produces a better brake surface.

Actually, the welding produces a worse brake surface, it's the
machining later on that produces a better brake surface.

strictly speaking, that's true, but the point is, pinned rims are often
misaligned and that can lead to braking issues - welded rims don't have
that problem.

A pinned rim can be aligned when the wheel is laced, but
before tensioning. I did this all the time. Once tensioned
the mating surfaces cannot move with respect to one
another.

--
Michael Press

Kenny said:

I'm considering getting new 700c rims. One pair of rims is welded
together while the other pair is sleeved together. They both weigh the
same per rim at about 410 grams. From the perspective of the consumer
which type of rim is better?

What really matters most is which rim has the better quality of
construction, generally. You have to inspect the rims personally. If
the pinned section is rough to a thumb rubbed across it and / or you
can see gaps in it, it is not of good quality period. On the other
hand, if the welded rim has poor quality welding (various voids / low
areas or excessive roughness) then look elsewhere. Also look at the
quality of workmanship of the sockets & eyelets. Also consider weather
or not it has sockets. I prefer double eyelets, but they are becoming
extinct. Velocity makes good rims w/o eyelets or sockets. European
brands are about the only ones making double eyeleted rims.
I have a slight preference for welded & machined, but I'll use
whichever one meets my needs. What brands / models are you considering?

Good luck, John

Michael Press said:

In article
<[email hidden]>,

jim beam said:

Donald Gillies said:

jim beam <[email hidden]> writes:

>welded.

>it has better fatigue properties [fwtw], usually has better weight
>distribution, and produces a better brake surface.

Actually, the welding produces a worse brake surface, it's the
machining later on that produces a better brake surface.

strictly speaking, that's true, but the point is, pinned rims are often
misaligned and that can lead to braking issues - welded rims don't have
that problem.

A pinned rim can be aligned when the wheel is laced, but
before tensioning. I did this all the time. Once tensioned
the mating surfaces cannot move with respect to one
another.

sure, it can be done, but

1. it's not a task most people do since they buy their wheels pre-built.
2. if you /do/ do it, it's a pita you don't have on welded rims.
3. it's not true that the surfaces can't move once built. i know jobst
makes that kind of statement frequently, but he's mistaken.

The one which is roundest and truest before it's laced. This is
important for correct spoke tension.

- -
Comments and opinions compliments of,
"Your Friendly Neighborhood Wheelman"

My web Site:
http "colon-slash-slash" geocities "dot" com "slash" czcorner

To E-mail me:
ChrisZCorner "at" webtv "dot" net

From: [email hidden] (jim beam)

Quoted message said:

Actually, the welding produces a worse
brake surface, it's the machining later on
that produces a better brake surface.
strictly speaking, that's true, but the point
is, pinned rims are often misaligned and
that can lead to braking issues - welded
rims don't have that problem.

Also untrue, as you put it. In order to result in a true, correctly
tensioned wheel with a smooth , even braking surface the extrusion from
which the weded rim is made from must first be perfectly circular to
begin with, it must be jigged correctly to maintain it's circularity and
this must be maintained untill the rim is cooled (and tested after) to
insure it stays round.

I have had a few welded rims, fine quality ones, that had a most
annoying hop at the weld joint and could not betrued out because these
procedures were NOT followed. Whichever you choose, welded or pinned
make sure the radius through the joint is identical to the rest of the
rim, not just machined smooth.

- -
Comments and opinions compliments of,
"Your Friendly Neighborhood Wheelman"

My web Site:
http "colon-slash-slash" geocities "dot" com "slash" czcorner

To E-mail me:
ChrisZCorner "at" webtv "dot" net

In article <[email hidden]>,

jim beam said:

Michael Press said:

In article
<[email hidden]>,

jim beam said:

Donald Gillies wrote:

>jim beam <[email hidden]> writes:
>
>
>
>>welded.
>
>
>>it has better fatigue properties [fwtw], usually has better weight
>>distribution, and produces a better brake surface.
>
>
>Actually, the welding produces a worse brake surface, it's the
>machining later on that produces a better brake surface.

strictly speaking, that's true, but the point is, pinned rims are often
misaligned and that can lead to braking issues - welded rims don't have
that problem.

A pinned rim can be aligned when the wheel is laced, but
before tensioning. I did this all the time. Once tensioned
the mating surfaces cannot move with respect to one
another.

sure, it can be done, but

1. it's not a task most people do since they buy their wheels pre-built.
2. if you /do/ do it, it's a pita you don't have on welded rims.
3. it's not true that the surfaces can't move once built. i know jobst
makes that kind of statement frequently, but he's mistaken.

I made that statement. I stand by it. Wheels I built did
not shift at the rim joint.

--
Michael Press

Michael Press said:

In article <[email hidden]>,
jim beam <[email hidden]> wrote:

Quoted message said:

Quoted message said:

sure, it can be done, but

1. it's not a task most people do since they buy their wheels pre-built.
2. if you /do/ do it, it's a pita you don't have on welded rims.
3. it's not true that the surfaces can't move once built. i know jobst
makes that kind of statement frequently, but he's mistaken.

I made that statement. I stand by it. Wheels I built did
not shift at the rim joint.

I've used lots of cheap wheels/rims that weren't welded, and I've never
had any problems with the rim joints. If I did, I'd just sand down the
bump and get on with life -- no different than rim "machining".

Michael Press said:

In article <[email hidden]>,

jim beam said:

Michael Press said:

In article
<[email hidden]>,
jim beam <[email hidden]> wrote:

>Donald Gillies wrote:
>
>>jim beam <[email hidden]> writes:
>>
>>
>>
>>>welded.
>>
>>
>>>it has better fatigue properties [fwtw], usually has better weight
>>>distribution, and produces a better brake surface.
>>
>>
>>Actually, the welding produces a worse brake surface, it's the
>>machining later on that produces a better brake surface.
>
>strictly speaking, that's true, but the point is, pinned rims are often
>misaligned and that can lead to braking issues - welded rims don't have
>that problem.

A pinned rim can be aligned when the wheel is laced, but
before tensioning. I did this all the time. Once tensioned
the mating surfaces cannot move with respect to one
another.

sure, it can be done, but

1. it's not a task most people do since they buy their wheels pre-built.
2. if you /do/ do it, it's a pita you don't have on welded rims.
3. it's not true that the surfaces can't move once built. i know jobst
makes that kind of statement frequently, but he's mistaken.

I made that statement. I stand by it. Wheels I built did
not shift at the rim joint.

It's a fine point, but it draws a fine line; "Wheels I built did
not shift at the rim joint" and "cannot move" are different things.

One's a matter of practical experience the other is a theory.

The difference between theory and practice is that in theory there's no
difference.

Ron

In article <[email hidden]>,

RonSonic said:

Michael Press said:

In article <[email hidden]>,

jim beam said:

Michael Press wrote:
> In article
> <[email hidden]>,
> jim beam <[email hidden]> wrote:
>
>
>>Donald Gillies wrote:
>>
>>>jim beam <[email hidden]> writes:
>>>
>>>
>>>
>>>>welded.
>>>
>>>
>>>>it has better fatigue properties [fwtw], usually has better weight
>>>>distribution, and produces a better brake surface.
>>>
>>>
>>>Actually, the welding produces a worse brake surface, it's the
>>>machining later on that produces a better brake surface.
>>
>>strictly speaking, that's true, but the point is, pinned rims are often
>>misaligned and that can lead to braking issues - welded rims don't have
>>that problem.
>
>
> A pinned rim can be aligned when the wheel is laced, but
> before tensioning. I did this all the time. Once tensioned
> the mating surfaces cannot move with respect to one
> another.
>
sure, it can be done, but

1. it's not a task most people do since they buy their wheels pre-built.
2. if you /do/ do it, it's a pita you don't have on welded rims.
3. it's not true that the surfaces can't move once built. i know jobst
makes that kind of statement frequently, but he's mistaken.

I made that statement. I stand by it. Wheels I built did
not shift at the rim joint.

It's a fine point, but it draws a fine line; "Wheels I built did
not shift at the rim joint" and "cannot move" are different things.

One's a matter of practical experience the other is a theory.

The difference between theory and practice is that in theory there's no
difference.

In theory what is the compressive force at the joint?
~1147 N

What is the frictional force at the joint?
1200 N -> 1550 N

This is over 10000 kg of force resisting displacement of
the ends. Theory and practice are consistent.

Consider a 36 spoke wheel with spoke tension T = 100 N
T spoke tension
F compressive force at
the joint
coefficient of friction of Al 1.05 -> 1.35
F = 2 * T ( cos 5 + cos 15 + cos 25 + cos 35 + cos 45
+ cos 55 + cos 65 + cos 75 + cos 85 )
= 2 * T / (2 * sin 5)
~ 2 * 100 * 5.73685662283493
~ 1147 N

--
Michael Press

Ryan Cousineau said:

Kenny said:

One pair of rims is welded
together while the other pair is sleeved together. They both weigh the
same per rim at about 410 grams. From the perspective of the consumer
which type of rim is better?

The one with more spokes.

Now _there_ is a proper r.b.t answer to that question! I second that.

For my part, I have built with both good and bad examples of both
kinds. Assuming good versions of each, I *like* pinned rims better.
At its best, a pinned seam is more uniform than a welded one. At its
worst, a pinned rim with badly cut ends can be impossible to build into
a sound wheel. In my experience, a good welded rim isn't as nice as a
good pinned one, and a bad welded rim is not so awful as a bad pinned
one.

What I like best of all is a rim that is basically true when all the
spokes are equally tensioned. Those can be had in both welded and
pinned versions-- according to the luck of the draw. I have built
wheels on new rims from Mavic, Sun, Alex, Velocity, Campagnolo, Araya,
Rigida, Wolber, Specialized, Weinmann, Matrix, Ritchey, Ukai, and a
handful of less noteworthy manufacturers. Unfortunately, I have found
no manufacturer whose products are so uniform that they don't usually
require significant tension variation at the joint. When I build up a
wheel that doesn't need much fiddling at the joint, I consider it a
rare treat.

Only once in my memory have I ever built up a wheel that was perfectly
true and tensioned after each spoke had been given the exact same
number of turns. That was a (pinned) 48 hole Sun Rhyno rim built on a
hub I machined myself. I was as elated as if I had witnessed an actual
miracle.

Chalo Colina

Michael Press said:

In article <[email hidden]>,

RonSonic said:

Michael Press said:

In article <[email hidden]>,
jim beam <[email hidden]> wrote:

>Michael Press wrote:
>
>>In article
>><[email hidden]>,
>> jim beam <[email hidden]> wrote:
>>
>>
>>
>>>Donald Gillies wrote:
>>>
>>>
>>>>jim beam <[email hidden]> writes:
>>>>
>>>>
>>>>
>>>>
>>>>>welded.
>>>>
>>>>
>>>>>it has better fatigue properties [fwtw], usually has better weight
>>>>>distribution, and produces a better brake surface.
>>>>
>>>>
>>>>Actually, the welding produces a worse brake surface, it's the
>>>>machining later on that produces a better brake surface.
>>>
>>>strictly speaking, that's true, but the point is, pinned rims are often
>>>misaligned and that can lead to braking issues - welded rims don't have
>>>that problem.
>>
>>
>>A pinned rim can be aligned when the wheel is laced, but
>>before tensioning. I did this all the time. Once tensioned
>>the mating surfaces cannot move with respect to one
>>another.
>>
>
>sure, it can be done, but
>
>1. it's not a task most people do since they buy their wheels pre-built.
>2. if you /do/ do it, it's a pita you don't have on welded rims.
>3. it's not true that the surfaces can't move once built. i know jobst
>makes that kind of statement frequently, but he's mistaken.

I made that statement. I stand by it. Wheels I built did
not shift at the rim joint.

It's a fine point, but it draws a fine line; "Wheels I built did
not shift at the rim joint" and "cannot move" are different things.

One's a matter of practical experience the other is a theory.

The difference between theory and practice is that in theory there's no
difference.

In theory what is the compressive force at the joint?
~1147 N

What is the frictional force at the joint?
1200 N -> 1550 N

This is over 10000 kg of force resisting displacement of
the ends.

10,000kg??? check that # michael.

Quoted message said:

Theory and practice are consistent.

Consider a 36 spoke wheel with spoke tension T = 100 N
T spoke tension
F compressive force at
the joint
coefficient of friction of Al 1.05 -> 1.35
F = 2 * T ( cos 5 + cos 15 + cos 25 + cos 35 + cos 45
+ cos 55 + cos 65 + cos 75 + cos 85 )
= 2 * T / (2 * sin 5)
~ 2 * 100 * 5.73685662283493
~ 1147 N

Michael Press said:

This is over 10000 kg of force resisting displacement of
the ends. Theory and practice are consistent.

Consider a 36 spoke wheel with spoke tension T = 100 N
T spoke tension
F compressive force at
the joint
coefficient of friction of Al 1.05 -> 1.35
F = 2 * T ( cos 5 + cos 15 + cos 25 + cos 35 + cos 45
+ cos 55 + cos 65 + cos 75 + cos 85 )
= 2 * T / (2 * sin 5)
~ 2 * 100 * 5.73685662283493
~ 1147 N

Alas, your practice of the theory wrong. First, 100 N is a very low
tension (about 20 lbf). Second, and more significantly, your equation
for the force is wrong. The easy way to compute the rim compression
is to assume that the force applied by the spokes can be uniformly
distributed over the circumference of the rims. It then acts like a
pressure. Split the rim on a diameter and integrate the pressure
across the diameter and set equal to twice the compressive force in
the rim (Fc).

2*Fc = p*D = (n*T/pi/D)*D

so

Fc = n*T/2/pi.

For a 36 spoke wheel with a spoke tension of 90 kgf,
the compressive force in the rim is then

Fc = (36)(100 kgf)/2/pi ~ 500 kgf ~ 1100 lbf.

--
Joe Riel