Why no sapphire / diamond chainwheels, cogs, or chains?

Weisse Luft wrote:
RonSonic Wrote:

On Sun, 15 Aug 2004 18:15:58 -0600, wrote:


On Sun, 15 Aug 2004 16:52:09 -0700, jim beam
wrote:


depends on morphology. if it's sufficiently rough it will. if it's
smooth, and fine, it will extend wear considerably.

wrote:

On Thu, 12 Aug 2004 16:19:05 GMT, none
wrote:



Why aren't there any bicycle chainwheels or chain side plates /

rivets

coated with sapphire or diamond? Wouldn't this help to decrease

wear on

these components?

-Mike


Dear Mike,

Coating things with hard grit like diamond dust turns them
into sandpaper, the opposite of the smooth surface that you
want.

Carl Fogel

Dear Jim,

So it looks as if at a fine enough level I'm wrong again.

I dunno, if you make the diamond fine enough you get graphite a pretty
decent
lubricant. Well yeah, that's at the molecular level, but you did say
"really
fine" didn't you.

Ron

No. Graphite is a planar crystalline unit cell allotrope of carbon.
Diamond is a tetrahedral unit cell crystal. You cannot grind diamonds
into graphite, you must pyrolyze and recondense the carbon vapors of a
diamond to get graphite.

Unless you are riding in diamond dust, stick with nitriding of the
chain.

ron may be alluding to some research that's been done on lubricants that
contain fine diamond - the idea being to take advantage of diamond's
thermal conductance while maintaining an acceptible wear rate.

Weisse Luft wrote:
RonSonic Wrote:

On Sun, 15 Aug 2004 18:15:58 -0600, wrote:


On Sun, 15 Aug 2004 16:52:09 -0700, jim beam
wrote:


depends on morphology. if it's sufficiently rough it will. if it's
smooth, and fine, it will extend wear considerably.

wrote:

On Thu, 12 Aug 2004 16:19:05 GMT, none
wrote:



Why aren't there any bicycle chainwheels or chain side plates /

rivets

coated with sapphire or diamond? Wouldn't this help to decrease

wear on

these components?

-Mike


Dear Mike,

Coating things with hard grit like diamond dust turns them
into sandpaper, the opposite of the smooth surface that you
want.

Carl Fogel

Dear Jim,

So it looks as if at a fine enough level I'm wrong again.

I dunno, if you make the diamond fine enough you get graphite a pretty
decent
lubricant. Well yeah, that's at the molecular level, but you did say
"really
fine" didn't you.

Ron

No. Graphite is a planar crystalline unit cell allotrope of carbon.
Diamond is a tetrahedral unit cell crystal. You cannot grind diamonds
into graphite, you must pyrolyze and recondense the carbon vapors of a
diamond to get graphite.

Unless you are riding in diamond dust, stick with nitriding of the
chain.

ron may be alluding to some research that's been done on lubricants that
contain fine diamond - the idea being to take advantage of diamond's
thermal conductance while maintaining an acceptible wear rate.

Weisse Luft wrote in message ...
Weisse Luft wrote in message ...

Dura Ace 9s chains have incredibly hard surface on the pins which
places

No, I pulled a Hyperglide chain off a bike that had several years of
college student inattention. Each pin had deep grooves in it from the
sideplates. Wear was about 1/4" over 12" of chain.

Dura Ace is much higher quality than low-level Hyperglide like HG-70.

Wasn't a HG, it is a Shimano 600 narrow UG has 1/16" 'stretch over 12" I
used it for at least two years cleaning with kerosene and re-oiling in a
bath every three months. So it covered at least 20 000 miles, not bad
considering training and racing on it as well as transport for work and day
tours. Looks like that steep price I paid for it may just have been worth
it. 16 pounds in 1986

Trevor

Weisse Luft wrote in message ...
Weisse Luft wrote in message ...

Dura Ace 9s chains have incredibly hard surface on the pins which
places

No, I pulled a Hyperglide chain off a bike that had several years of
college student inattention. Each pin had deep grooves in it from the
sideplates. Wear was about 1/4" over 12" of chain.

Dura Ace is much higher quality than low-level Hyperglide like HG-70.

Wasn't a HG, it is a Shimano 600 narrow UG has 1/16" 'stretch over 12" I
used it for at least two years cleaning with kerosene and re-oiling in a
bath every three months. So it covered at least 20 000 miles, not bad
considering training and racing on it as well as transport for work and day
tours. Looks like that steep price I paid for it may just have been worth
it. 16 pounds in 1986

Trevor

On Mon, 16 Aug 2004 20:26:33 -0700, jim beam wrote:

Weisse Luft wrote:
RonSonic Wrote:

On Sun, 15 Aug 2004 18:15:58 -0600, wrote:


On Sun, 15 Aug 2004 16:52:09 -0700, jim beam
wrote:


depends on morphology. if it's sufficiently rough it will. if it's
smooth, and fine, it will extend wear considerably.

wrote:

On Thu, 12 Aug 2004 16:19:05 GMT, none
wrote:



Why aren't there any bicycle chainwheels or chain side plates /

rivets

coated with sapphire or diamond? Wouldn't this help to decrease

wear on

these components?

-Mike


Dear Mike,

Coating things with hard grit like diamond dust turns them
into sandpaper, the opposite of the smooth surface that you
want.

Carl Fogel

Dear Jim,

So it looks as if at a fine enough level I'm wrong again.

I dunno, if you make the diamond fine enough you get graphite a pretty
decent
lubricant. Well yeah, that's at the molecular level, but you did say
"really
fine" didn't you.

Ron

No. Graphite is a planar crystalline unit cell allotrope of carbon.
Diamond is a tetrahedral unit cell crystal. You cannot grind diamonds
into graphite, you must pyrolyze and recondense the carbon vapors of a
diamond to get graphite.

Unless you are riding in diamond dust, stick with nitriding of the
chain.

ron may be alluding to some research that's been done on lubricants that
contain fine diamond - the idea being to take advantage of diamond's
thermal conductance while maintaining an acceptible wear rate.

No, really I was just spoofing. The thought being graphite is a smaller crystal
of carbon than diamond - a facetious suggestion that diamond could be
mechanically ground or crushed into graphite. Just a bit of foolishness being
taken far too seriously.

Sorry.

Ron

On Mon, 16 Aug 2004 20:26:33 -0700, jim beam wrote:

Weisse Luft wrote:
RonSonic Wrote:

On Sun, 15 Aug 2004 18:15:58 -0600, wrote:


On Sun, 15 Aug 2004 16:52:09 -0700, jim beam
wrote:


depends on morphology. if it's sufficiently rough it will. if it's
smooth, and fine, it will extend wear considerably.

wrote:

On Thu, 12 Aug 2004 16:19:05 GMT, none
wrote:



Why aren't there any bicycle chainwheels or chain side plates /

rivets

coated with sapphire or diamond? Wouldn't this help to decrease

wear on

these components?

-Mike


Dear Mike,

Coating things with hard grit like diamond dust turns them
into sandpaper, the opposite of the smooth surface that you
want.

Carl Fogel

Dear Jim,

So it looks as if at a fine enough level I'm wrong again.

I dunno, if you make the diamond fine enough you get graphite a pretty
decent
lubricant. Well yeah, that's at the molecular level, but you did say
"really
fine" didn't you.

Ron

No. Graphite is a planar crystalline unit cell allotrope of carbon.
Diamond is a tetrahedral unit cell crystal. You cannot grind diamonds
into graphite, you must pyrolyze and recondense the carbon vapors of a
diamond to get graphite.

Unless you are riding in diamond dust, stick with nitriding of the
chain.

ron may be alluding to some research that's been done on lubricants that
contain fine diamond - the idea being to take advantage of diamond's
thermal conductance while maintaining an acceptible wear rate.

No, really I was just spoofing. The thought being graphite is a smaller crystal
of carbon than diamond - a facetious suggestion that diamond could be
mechanically ground or crushed into graphite. Just a bit of foolishness being
taken far too seriously.

Sorry.

Ron

RonSonic wrote in message ...
No, really I was just spoofing. The thought being graphite is a smaller
crystal
of carbon than diamond - a facetious suggestion that diamond could be
mechanically ground or crushed into graphite. Just a bit of foolishness
being
taken far too seriously.

Buckyballs.

Trevor