Beat rim into true or not?

App said:

After a recent crash I have discovered a permanent bend in my front
rim, more of a single wave that extends about 1/4 of the way around the
rim. Laying the rim on the floor after disassembling the wheel, the
max out of true is ~1/4". There doesn't seem to be a kink in it,but
rather a smooth wave.

How wobbly was the wheel before disassembly? How uneven was the spoke
tension? If the spoke tension was very uneven, throw that rim away and
rebuild the wheel.
Why did you disassemble the wheel? Do you mean you unlaced it, or
loosened the nipples, or what? You can straighten rims by hitting them
with a mallet while the bent section is between two 2x4s. Whether
you'll have a round, straight wheel with safe spoke tension is another
issue. Might be time for a new rim, especially since the one you bent
is so lightweight.

-Vee

search to: 'DIY rim repair tool 2' in tech archives

App said:

After a recent crash I have discovered a permanent bend in my front
rim, more of a single wave that extends about 1/4 of the way around the
rim. Laying the rim on the floor after disassembling the wheel, the
max out of true is ~1/4". There doesn't seem to be a kink in it,but
rather a smooth wave.

Would you beat on the rim with a rubber mallet or just bring it into
true with the spokes?

Oh, yeah, rim is Open Pro 36 spoke.

There is little to be lost by trying to straighten it, but much to be
gained by doing so carefully and well. It's all a matter of value,
though; is an hour or two of your time spent in trying to get it
flattened worth more than the cost of the replacement rim? If the
answer is "yes", then just buy a new rim and either discard the bent
one or hang on to it for one of those odd moments when you really have
nothing else to do.

--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

App said:

After a recent crash I have discovered a permanent bend in my front
rim, more of a single wave that extends about 1/4 of the way around the
rim. Laying the rim on the floor after disassembling the wheel, the
max out of true is ~1/4". There doesn't seem to be a kink in it,but
rather a smooth wave.

If the rim isn't flat - if it rises 1/4" above the table on one side -
then that's not really a problem. An Open Pro aluminum rim 1/4" out of
true can easily be pulled straight by the spokes (especially if its a
32 or 36 spoke wheel), because it's a light aluminum rim and the
spokes control the rim (the same cannot be said for a heavy rim or a
steel rim.)

I think that many rims start out their life (before truing) with this
much bend in them. It could be that your rim came from the factory
with this problem.

If the rim has a problem on one side and not another, then i'd be much
more concerned, that is quite unusual, and I would probably purchase
another rim.

- Don Gillies
San Diego, CA

App said:

After a recent crash I have discovered a permanent bend in my front
rim, more of a single wave that extends about 1/4 of the way around the
rim. Laying the rim on the floor after disassembling the wheel, the
max out of true is ~1/4". There doesn't seem to be a kink in it,but
rather a smooth wave.

Would you beat on the rim with a rubber mallet or just bring it into
true with the spokes?

Oh, yeah, rim is Open Pro 36 spoke.

Given the amount of hassle involved in trying to get it straight, I'd
buy a new rim - especially as this is a current production model so you
can get a match.

I had a slightly bent Open 4CD which built into a wheel which was
straight, but predictably had uneven spoke tension. I saved the spokes
and put a cheap MA3 on there instead (MA3 and Open 4CD are virtually the
same ERD), and all is well.

Don said:

I think that many rims start out their life (before truing) with this
much bend in them. It could be that your rim came from the factory
with this problem.
If the rim has a problem on one side and not another, then i'd be much
more concerned, that is quite unusual, and I would probably purchase
another rim.

Rim was perfectly true prior to build; crash rendered it bent. What do
you mean "on one side and not another"?

Do you mean that the rim has been compressed laterally (box section is
squished)? 'Cuz that isn't the case. The rim simply is out of true in
a semi-sinusoidal fashion with only one phase. Maybe 1/2 phase?,
anyway, the rest of the rim is true and the "bent" section is out to
one side ~1/4" at it's greatest excursion.

Anyway, based on the info/opinion in the responses, I am going to
rebuild it (coupla bent spokes when I de-tensioned the wheel so I fully
disassembled it and threw out the bent ones) without wanking on it.

I'll post results of that rebuild including spoke tension in that
region by spoke.

Thanks for all your input.

App

The sometimes undeniable Zog said:

especially as this is a current production model so you
can get a match.

Sadly, no. It is the RED open pro. Available only as NOS. So I'll
give it a whirl - don't think it'll be too bad - flattening the bent
section by leaning on the rim on the floor took only small amount of
pressure.

I could get a black or silver replacement, but, hey, aesthetics DO
matter.

I am going to try - 1.5 hours to very possibly save myself the effort
of finding another NOS red OP rim. Plus, I just built the damn things.
Worth it, I think.

App

App said:

After a recent crash I have discovered a permanent bend in my front
rim, more of a single wave that extends about 1/4 of the way around the
rim. Laying the rim on the floor after disassembling the wheel, the
max out of true is ~1/4". There doesn't seem to be a kink in it,but
rather a smooth wave.

Would you beat on the rim with a rubber mallet or just bring it into
true with the spokes?

Oh, yeah, rim is Open Pro 36 spoke.

I recently had a rim that was bent worse than that, courtesy of being
in a cargo trailer with a bunch of other bikes during a serious
accident. For what it's worth it's an Alex DA16, 700c, 36 spoke.

It never occurred to me to try to beat it with a rubber mallet.
Instead I removed the rim from the wheel, first taping the spokes
together at their outer crosses. I laid the rim on a carpeted surface,
concave side down, with the out-of-round spot resting on one leg of my
work stand. I jumped up and down on the two high spots (one foot on
each spot), then checked for flatness on my coffee table.

A few iterations of the above and the rim was pretty flat again. I
relaced it, tensioned and trued, and am still using that wheel. In
fact I'm planning on climbing Going-to-the-Sun Road in Glacier
National Park on that bike next week. ;-)

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

quote='App'The sometimes undeniable Zog said:

especially as this is a current production model so you
can get a match.

Sadly, no. It is the RED open pro. Available only as NOS. So I'll
give it a whirl - don't think it'll be too bad - flattening the bent
section by leaning on the rim on the floor took only small amount of
pressure.

I could get a black or silver replacement, but, hey, aesthetics DO
matter.

I am going to try - 1.5 hours to very possibly save myself the effort
of finding another NOS red OP rim. Plus, I just built the damn things.
Worth it, I think.

App[/QUOTE]

I broke a mallet trying this once, the steel Schwinn rim barely returned back toward round so I gave up and bought another wheel.

I still have the wheel, and it could still be ridden at slow speed, but even if straightened would leave me wondering about the strength of the wheel if I was at speed.

App said:

After a recent crash I have discovered a permanent bend in my front
rim, more of a single wave that extends about 1/4 of the way around the
rim. Laying the rim on the floor after disassembling the wheel, the
max out of true is ~1/4". There doesn't seem to be a kink in it,but
rather a smooth wave.

Would you beat on the rim with a rubber mallet or just bring it into
true with the spokes?

Oh, yeah, rim is Open Pro 36 spoke.

I've straightened bent rims many times, but only ones bent inward due
to pothole hits. FWIW, on my 1972 commute bike I'm riding Weinmann
A-129 rims that date from about 1980. They've had those kinks removed
many time.

But I used a more controllable technique than the mallet. I made a
fixture out of two-by-fours that allowed me to work out the dents using
a bench vise. It supports the rim to the two sides of the dent, and
the vise applies pressure in the center. Works well.

Based on this, I'd assume a little side-to-side straightening would be
easy.

- Frank Krygowski

"John Everett" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

App said:

After a recent crash I have discovered a permanent bend in my front
rim, more of a single wave that extends about 1/4 of the way around the
rim. Laying the rim on the floor after disassembling the wheel, the
max out of true is ~1/4". There doesn't seem to be a kink in it,but
rather a smooth wave.

Would you beat on the rim with a rubber mallet or just bring it into
true with the spokes?

Oh, yeah, rim is Open Pro 36 spoke.

I recently had a rim that was bent worse than that, courtesy of being
in a cargo trailer with a bunch of other bikes during a serious
accident. For what it's worth it's an Alex DA16, 700c, 36 spoke.

It never occurred to me to try to beat it with a rubber mallet.
Instead I removed the rim from the wheel, first taping the spokes
together at their outer crosses. I laid the rim on a carpeted surface,
concave side down, with the out-of-round spot resting on one leg of my
work stand. I jumped up and down on the two high spots (one foot on
each spot), then checked for flatness on my coffee table.

I do this too. It's not an exact science... People that obsess about that
0.5kgf deviation on the one or two spokes probably need another hobby.

--
Phil, Squid-in-Training

Phil said:

"John Everett" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

App said:

After a recent crash I have discovered a permanent bend in my front
rim, more of a single wave that extends about 1/4 of the way around the
rim. Laying the rim on the floor after disassembling the wheel, the
max out of true is ~1/4". There doesn't seem to be a kink in it,but
rather a smooth wave.

Would you beat on the rim with a rubber mallet or just bring it into
true with the spokes?

Oh, yeah, rim is Open Pro 36 spoke.

I recently had a rim that was bent worse than that, courtesy of being
in a cargo trailer with a bunch of other bikes during a serious
accident. For what it's worth it's an Alex DA16, 700c, 36 spoke.

It never occurred to me to try to beat it with a rubber mallet.
Instead I removed the rim from the wheel, first taping the spokes
together at their outer crosses. I laid the rim on a carpeted surface,
concave side down, with the out-of-round spot resting on one leg of my
work stand. I jumped up and down on the two high spots (one foot on
each spot), then checked for flatness on my coffee table.

I do this too. It's not an exact science... People that obsess about that
0.5kgf deviation on the one or two spokes probably need another hobby.

--
Phil, Squid-in-Training

I guess I was reluctant to try the beating method. I just never have
had to do this to a rim before and the very idea of taking a sledge or
large mallet to it sounded so much like a joke. However, I just found
out, not so. I guess a little patience and thought will sometimes win
out over inexperience.

Anyway, left the wheel detensioned but built and spun it in the fork to
check where it was off. Marked a coupla out-of-true arcs and clamped
the wheel down on two sawhorses (placing a 2x2 on top to keep from
marring the wheel), one of the arcs extended out of the sandwich
created by the top of the sawhorse and the 2x2 and beating the exposed
arc with a large rubber mallet. I clamped the part of the wheel
opposite down to the other sawhorse for lever arm against the mallet
blows. Stubborn areas got the 2 lb sledge and a chunk of hardwood
treatment. Hit more often in the center of the arc where the the
lateral excursion was the greatest.

I also used a woodworking clamp (the one with the twin screws and the
hardwood jaws) to grab the rim in a large area and bend it. I found
the beating method to be the most controlled (I probably beat the 6 mm
out area 15 - 20 times to get it back ~1 mm).

As it sits, max out of true appears to be ~1 mm. Think I am going to
quit while I am ahead.

App

meb said:

App said:

I am going to try - 1.5 hours to very possibly save myself the effort
of finding another NOS red OP rim. Plus, I just built the damn
things.
Worth it, I think.

App

I broke a mallet trying this once, the steel Schwinn rim barely
returned back toward round so I gave up and bought another wheel.

I still have the wheel, and it could still be ridden at slow speed, but
even if straightened would leave me wondering about the strength of the
wheel if I was at speed.

You obviously were not using the Schwinn Special Tool, then. Here's
the current version:

http://www.lowes.com/lowes/lkn?action=productDetail&productId=147583-302-1118400&lpage=none

alias

http://tinyurl.com/c7wva

This is the one for "fine adjustments"; the one for "large
adjustments" is bigger. (The version for working on road bikes has a
taped handle, but is otherwise identical.)

This should not be confused with the Universal Schwinn Alignment Tool
which is used when extreme difficulty in achieving acceptable
operation has been encountered, to ensure that everything on the bike
is adjusted into the same plane:

http://www.steam-up.co.uk/marshall/marshall_apx542.htm

Once so adjusted, most Schwinns require no further attention.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

John Everett said:

In
fact I'm planning on climbing Going-to-the-Sun Road in Glacier
National Park on that bike next week. ;-)

AAARGH! I haven't been able to cobble together an excuse to hit
Glacier in nearly 30 years. I am envious, I tell you, *envious*.

(Candidly, I'd never be able to keep up with you on that climb. I
recall the road well, though. Lots of visual anesthesia to take one's
mind off the effort. Beware of the sheep and the drivers; neither
will give you any room.)
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

Werehatrack said:

On Sat, 16 Jul 2005 05:25:43 +1000, meb

Quoted message said:

App said:

I am going to try - 1.5 hours to very possibly save myself the effort
of finding another NOS red OP rim. Plus, I just built the damn
things.
Worth it, I think.

App

I broke a mallet trying this once, the steel Schwinn rim barely
returned back toward round so I gave up and bought another wheel.

I still have the wheel, and it could still be ridden at slow speed, but
even if straightened would leave me wondering about the strength of the
wheel if I was at speed.

You obviously were not using the Schwinn Special Tool, then. Here's
the current version:

http://www.lowes.com/lowes/lkn?action=productDetail&productId=147583-302-1118400&lpage=none

alias

http://tinyurl.com/c7wva

This is the one for "fine adjustments"; the one for "large
adjustments" is bigger. (The version for working on road bikes has a
taped handle, but is otherwise identical.)

This should not be confused with the Universal Schwinn Alignment Tool
which is used when extreme difficulty in achieving acceptable
operation has been encountered, to ensure that everything on the bike
is adjusted into the same plane:

http://www.steam-up.co.uk/marshall/marshall_apx542.htm

Once so adjusted, most Schwinns require no further attention.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

Your speculation is correct that I didn't try the Schwinn Special Tool. The high tech design of the special tool emphatically illustrates the shortcomings of the rubber mallet: a wooden handle that broke after chunks of the rubber head had seperated. The Schwinn Special Tool in the hands of a master craftsman such as Thor would appear to capable of forcing any misaligned rim or many other finicky appliances away from their malfunctioning state.

Is the Universal Schwinn alignment tool suitable for use on frames as well as wheels?

the best deal is get a new rim, then straighten the old one when time
allows-this gives riding pleasure, wheel building skills, and a spare
wheel assembly. the spare corrects a multitude of problems including
premature death

Werehatrack said:

John Everett said:

In
fact I'm planning on climbing Going-to-the-Sun Road in Glacier
National Park on that bike next week. ;-)

AAARGH! I haven't been able to cobble together an excuse to hit
Glacier in nearly 30 years. I am envious, I tell you, *envious*.

Going-to-the-Sun Road turned out to be a non-starter. Seems we were
about half way from Illinois to Montana when we realized that while
our bikes were firmly locked into the fork mounts on the roof of the
car, our front wheels were still sitting in the garage. :-(

While the trip was mainly for hiking and backpacking, we did manage to
get in a ride courtesy of Lee Stanley at Glacier Cyclery in Whitefish.
He rented us a couple of front wheels and we got in a ride up the east
shore road at Hungry Horse Reservoir. :-)

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

Werehatrack said:

John Everett said:

In
fact I'm planning on climbing Going-to-the-Sun Road in Glacier
National Park on that bike next week. ;-)

AAARGH! I haven't been able to cobble together an excuse to hit
Glacier in nearly 30 years. I am envious, I tell you, *envious*.

Going-to-the-Sun Road turned out to be a non-starter. Seems we were
about half way from Illinois to Montana when we realized that while
our bikes were firmly locked into the fork mounts on the roof of the
car, our front wheels were still sitting in the garage. :-(

While the trip was mainly for hiking and backpacking, we did manage to
get in a ride courtesy of Lee Stanley at Glacier Cyclery in Whitefish.
He rented us a couple of front wheels and we got in a ride up the east
shore road at Hungry Horse Reservoir. :-)

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

Werehatrack said:

John Everett said:

In
fact I'm planning on climbing Going-to-the-Sun Road in Glacier
National Park on that bike next week. ;-)

AAARGH! I haven't been able to cobble together an excuse to hit
Glacier in nearly 30 years. I am envious, I tell you, *envious*.

Going-to-the-Sun Road turned out to be a non-starter. Seems we were
about half way from Illinois to Montana when we realized that while
our bikes were firmly locked into the fork mounts on the roof of the
car, our front wheels were still sitting in the garage. :-(

While the trip was mainly for hiking and backpacking, we did manage to
get in a ride courtesy of Lee Stanley at Glacier Cyclery in Whitefish.
He rented us a couple of front wheels and we got in a ride up the east
shore road at Hungry Horse Reservoir. :-)

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3