bearings chromium or carbon

[Peter Cole]

* * Chas wrote:
> "Peter Cole" <[email protected]> wrote in message
> newsj1Lj.3204$XC1.161@trndny08...
>> Walt Shekrota wrote:
>>> Is there a difference? Can you use the wrong ones?
>>> Thanks.
>>> -Walt
>> "Chrome steel" is a steel alloy with 1-2% chromium added for corrosion
>> resistance. True stainless steels have much more chromium (>12%) and are
>> much more corrosion resistant, but are much more expensive to make in
>> the hardness required for bicycle bearings.
>>
>> Most bicycles use chrome steel balls, they're cheap enough, and have
>> enough corrosion resistance for most environments. For a bit of added
>> protection some people pack with marine grease. If you buy balls at a
>> bike shop you'll almost certainly get chrome steel. They're also
>> commonly available from broad-line industrial suppliers like
>> McMaster-Carr. A few bucks buys you a lifetime's supply.
>
> The 1.3% to 1.6% chrome in 52100 bearing steel has nothing to do with
> corrosion resistance. Chrome is added to steel in small quantities to
> increase strength and hardenability. The chrome mixes with carbon in the
> steel to form chrome carbides.

From the site you cited upthread:

" Chrome Steel Balls Vs Carbon Steel Balls

For better performance and life in most of the above applications chrome
steel balls instead of ordinary carbon steel ball (round / spherical)
are preferred. These steel balls have better ***corrosion resistance***,
hardenability and toughness. "


> It takes much higher levels of chrome for corrosion resistance. Stainless
> steels or corrosion resistant steels contain at least 10% chrome plus
> other alloys.

Corrosion resistance is a matter of degree.

Since carbon steel and chrome steel balls seem to be made to identical
hardness, I don't think that's an advantage. Toughness/fatigue/strength
sure, perhaps enough to mandate use in bikes, perhaps not.

 

[Peter Cole]

* * Chas wrote:
> "Peter Cole" <[email protected]> wrote in message

>> In the book "Bearing Steel Technology" By John M. Beswick, chrome steel
>> (through hardened) ball bearings were tested against case hardened
>> carbon steel (3312) balls when running in deliberately dented races. The
>> case hardened balls had 2-3x the lifetime (time to spall failure).
>>
>> Not sure that has any significance except to indicate that case hardened
>> balls aren't completely bad, with a light load they might actually be
>> better.
>
> The premise behind ball bearings is to reduce rotational friction. As
> such, dented races defeat the purpose of a ball bearing which is designed
> to run in a smooth track.

The premise was to simulate the typical wear related damage seen in
bearing races. Such wear comes from race denting from both externally
introduced particles and/or the particles from wear itself.

> If these results are true then case hardened ball bearing would be a
> better choice for use in a worn out headset.

Only if ball fatigue (spalling) was a factor in bearing lifetime.


>
> Case hardening is commonly used in sliding applications such as the shafts
> in a transmission rather than the continuos rotation of a bearing.
>
> Headsets are thrust bearings with heavy axial loading with very little
> radial or rotational forces. Almost every frame that I've worked on needed
> to have the head tube and fork crown faced for proper headset alignment. I
> think that poor headset fit is a major cause of premature race failure.

These days cassettes and even chains have gotten more expensive than
headsets, while even cheap headsets seem to be of much better quality.
As a result, I don't give them much thought. I suppose it's only a
matter of time before all bike bearings become assemblies and all these
issues become irrelevant.

 

[datakoll]

in the beginnig, question was carbon or Harris at 400% markup.
looking backwards, question was: why is carbon listed as a cycle
bearing?

leaving the chrome vanadium ball bearing to the Brandt Speculation and
brittle stainless to the Great Un-lubed

then only grade 25 hi chromium is relevant given time/labor/
intelligence or low chrmium if multiple rebuilds are suspected over
long mileages.

right?

only reason I asked the same question was the listing's existance

enevelope pohlease:

the LBS is using carbon bearings

 

[* * Chas]

"Peter Cole" <[email protected]> wrote in message
news:C8JLj.12417$Ug4.3061@trndny01...
> * * Chas wrote:
> > "Peter Cole" <[email protected]> wrote in message
>
> >> In the book "Bearing Steel Technology" By John M. Beswick, chrome
steel
> >> (through hardened) ball bearings were tested against case hardened
> >> carbon steel (3312) balls when running in deliberately dented races.
The
> >> case hardened balls had 2-3x the lifetime (time to spall failure).
> >>
> >> Not sure that has any significance except to indicate that case
hardened
> >> balls aren't completely bad, with a light load they might actually be
> >> better.
> >
> > The premise behind ball bearings is to reduce rotational friction. As
> > such, dented races defeat the purpose of a ball bearing which is
designed
> > to run in a smooth track.
>
> The premise was to simulate the typical wear related damage seen in
> bearing races. Such wear comes from race denting from both externally
> introduced particles and/or the particles from wear itself.
>
> > If these results are true then case hardened ball bearing would be a
> > better choice for use in a worn out headset.
>
> Only if ball fatigue (spalling) was a factor in bearing lifetime.
>
>
> >
> > Case hardening is commonly used in sliding applications such as the
shafts
> > in a transmission rather than the continuos rotation of a bearing.
> >
> > Headsets are thrust bearings with heavy axial loading with very little
> > radial or rotational forces. Almost every frame that I've worked on
needed
> > to have the head tube and fork crown faced for proper headset
alignment. I
> > think that poor headset fit is a major cause of premature race
failure.
>
> These days cassettes and even chains have gotten more expensive than
> headsets, while even cheap headsets seem to be of much better quality.
> As a result, I don't give them much thought. I suppose it's only a
> matter of time before all bike bearings become assemblies and all these
> issues become irrelevant.

It was late. I should have qualified my statement. I was talking about old
style 1" headsets. Custom frame builders, primarily in the US did a lot to
improve frame preparation quality. I've not worked on any bike newer than
the mid 90s so I don't know how well later model bikes are prepared for
headsets.

I agree, assemblies can be made much cheaper and better than loose bearing
cup and cone setups.

Chas.

 

[* * Chas]

"Peter Cole" <[email protected]> wrote in message
news:M_ILj.5505$XC1.4070@trndny08...
> * * Chas wrote:
> > "Peter Cole" <[email protected]> wrote in message
> > newsj1Lj.3204$XC1.161@trndny08...
> >> Walt Shekrota wrote:
> >>> Is there a difference? Can you use the wrong ones?
> >>> Thanks.
> >>> -Walt
> >> "Chrome steel" is a steel alloy with 1-2% chromium added for
corrosion
> >> resistance. True stainless steels have much more chromium (>12%) and
are
> >> much more corrosion resistant, but are much more expensive to make in
> >> the hardness required for bicycle bearings.
> >>
> >> Most bicycles use chrome steel balls, they're cheap enough, and have
> >> enough corrosion resistance for most environments. For a bit of added
> >> protection some people pack with marine grease. If you buy balls at a
> >> bike shop you'll almost certainly get chrome steel. They're also
> >> commonly available from broad-line industrial suppliers like
> >> McMaster-Carr. A few bucks buys you a lifetime's supply.
> >
> > The 1.3% to 1.6% chrome in 52100 bearing steel has nothing to do with
> > corrosion resistance. Chrome is added to steel in small quantities to
> > increase strength and hardenability. The chrome mixes with carbon in
the
> > steel to form chrome carbides.
>
> From the site you cited upthread:
>
> " Chrome Steel Balls Vs Carbon Steel Balls
>
> For better performance and life in most of the above applications chrome
> steel balls instead of ordinary carbon steel ball (round / spherical)
> are preferred. These steel balls have better ***corrosion resistance***,
> hardenability and toughness. "
>
>
> > It takes much higher levels of chrome for corrosion resistance.
Stainless
> > steels or corrosion resistant steels contain at least 10% chrome plus
> > other alloys.
>
> Corrosion resistance is a matter of degree.
>
> Since carbon steel and chrome steel balls seem to be made to identical
> hardness, I don't think that's an advantage. Toughness/fatigue/strength
> sure, perhaps enough to mandate use in bikes, perhaps not.

" ***corrosion resistance*** " Advertising hyperbole....

Chas.

 

[Peter Cole]

* * Chas wrote:
> "Peter Cole" <[email protected]> wrote in message

>> For better performance and life in most of the above applications chrome
>> steel balls instead of ordinary carbon steel ball (round / spherical)
>> are preferred. These steel balls have better ***corrosion resistance***,
>> hardenability and toughness. "

> " ***corrosion resistance*** " Advertising hyperbole....

Not entirely, from what I've read. The improvement is modest compared to
stainless, but significant...

 

[Werehatrack]

On Fri, 11 Apr 2008 00:30:21 -0700, "* * Chas"
<[email protected]> may have said:

>
>"Werehatrack" <[email protected]> wrote in message
>news[email protected]...
>> On Tue, 08 Apr 2008 23:23:36 -0400, Walt Shekrota
>> <[email protected]> may have said:
>>
>> >Is there a difference? Can you use the wrong ones?
>>
>> Chrome is less likely to corrode. Carbon is generally cheaper.
>> Functionally, they are indistinguishable in any cycling application.
>> I tend to buy the chrome balls because I ride in a wet climate.
>>
>> --
>
>NOPE!
>
>The term "Chrome" has nothing to do with corrosion resistance when
>referring to loose ball bearings used in bicycles.
>
>"Chrome" ball bearings are made from AISI/SAE 52100 alloy steel that was
>developed for use in hardened steel bearings. It contains ~1% Carbon and
>1.3% to 1.6% Chrome.
>
>AISI = American Iron and Steel Institute
>SAE = Society of Automotive Engineers
>
>http://www.steelmedia.com/chrome-steel-balls.htm#Material
>
>"Carbon" ball bearings are made from lower quality "Carbon Steels" that
>lacks the addition of Chrome or other alloying materials found in "Alloy
>Steels".
>
>Carbon Steel ball bearings can be made from any non alloy steel from
>AISI/SAE 1015 to 1085. Ball bearings made from low carbon 1015-1018 steels
>are case hardened which means that they are only hardened on the outside.
>
>Higher carbon steel ball bearings made from 1060-1085 steel are through
>hardened.
>
>Fatigue resistance is the biggest difference between alloy and carbon
>steels.
>
>For the few pennies more it's not worth messing around with Carbon Steel
>ball bearings.
>
>Ball bearing Grades refer to measurements of roundness, diameter and
>surface roughness. Grade 25 is a good quality for use in loose bearings in
>bikes.
>
>http://americandad.biz/gradechart.htm

Then why, pray tell, do carbon balls develop surface corrosion within
hours (sometimes minutes) when water gets into the bag, but chrome
ones remain pristine for a useful period? I've had bags of both get
rained upon at the same time, when someone left the bearing box
outside; I stopped buying carbon balls becase they always rusted
before I could get them completely dried off. With the loading that
is present in a bicycle bearing assembly, the hardness difference is
unimportant; these bearings will never see a significant fraction of
their limits. But the chrome balls survive where the carbon ones
fail, and the observed resistance to corrosion (in hubs and other
locations that are at best poorly sealed if at all) is the only factor
I can see which explains it.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

 

[datakoll]

On Apr 11, 5:51 pm, Werehatrack <[email protected]> wrote:
> On Fri, 11 Apr 2008 00:30:21 -0700, "* * Chas"
> <[email protected]> may have said:
>
>
>
>
>
>
>
> >"Werehatrack" <[email protected]> wrote in message
> >news[email protected]...
> >> On Tue, 08 Apr 2008 23:23:36 -0400, Walt Shekrota
> >> <[email protected]> may have said:
>
> >> >Is there a difference? Can you use the wrong ones?
>
> >> Chrome is less likely to corrode.  Carbon is generally cheaper.
> >> Functionally, they are indistinguishable in any cycling application.
> >> I tend to buy the chrome balls because I ride in a wet climate.
>
> >> --
>
> >NOPE!
>
> >The term "Chrome"  has nothing to do with corrosion resistance when
> >referring to loose ball bearings used in bicycles.
>
> >"Chrome" ball bearings are made from AISI/SAE 52100 alloy steel that was
> >developed for use in hardened steel bearings. It contains ~1% Carbon and
> >1.3% to 1.6% Chrome.
>
> >AISI = American Iron and Steel Institute
> >SAE = Society of Automotive Engineers
>
> >http://www.steelmedia.com/chrome-steel-balls.htm#Material
>
> >"Carbon" ball bearings are made from lower quality "Carbon Steels" that
> >lacks the addition of Chrome or other alloying materials found in "Alloy
> >Steels".
>
> >Carbon Steel ball bearings can be made from any non alloy steel from
> >AISI/SAE 1015 to 1085. Ball bearings made from low carbon 1015-1018 steels
> >are case hardened which means that they are only hardened on the outside.
>
> >Higher carbon steel ball bearings made from 1060-1085 steel are through
> >hardened.
>
> >Fatigue resistance is the biggest difference between alloy and carbon
> >steels.
>
> >For the few pennies more it's not worth messing around with Carbon Steel
> >ball bearings.
>
> >Ball bearing Grades refer to measurements of roundness, diameter and
> >surface roughness. Grade 25 is a good quality for use in loose bearings in
> >bikes.
>
> >http://americandad.biz/gradechart.htm
>
> Then why, pray tell, do carbon balls develop surface corrosion within
> hours (sometimes minutes) when water gets into the bag, but chrome
> ones remain pristine for a useful period?  I've had bags of both get
> rained upon at the same time, when someone left the bearing box
> outside; I stopped buying carbon balls becase they always rusted
> before I could get them completely dried off.  With the loading that
> is present in a bicycle bearing assembly, the hardness difference is
> unimportant; these bearings will never see a significant fraction of
> their limits.  But the chrome balls survive where the carbon ones
> fail, and the observed resistance to corrosion (in hubs and other
> locations that are at best poorly sealed if at all) is the only factor
> I can see which explains it.
>
> --
> My email address is antispammed; pull WEEDS if replying via e-mail.
> Typoes are not a bug, they're a feature.
> Words processed in a facility that contains nuts.- Hide quoted text -
>
> - Show quoted text -

fileum then report back