Magnesium frames

A Muzi said:

Quoted message said:

[email hidden] (Appkiller) wrote in message

news:<[email hidden]>...

Quoted message said:

Quoted message said:

These are starting to appear - Pinarello has one, among others. Anyone know anything about
them besides marketing lies? Alloyed? Durability? How are they welded?

Not that I am interested in purchasing one, just curious.

"Tom D" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I don't know much, but they're not *that* new. I have a 1988 edition of Eugene Sloane's
_Complete Book of Bicycling_ that has an extended quote from Douglas Hayduk's _Bicycle
Metallurgy for the Cyclist_ (no date, but no later than 1988):

Quoted message said:

>Mg bike frames have very recently entered the market and are now

being mass-produced in England by Kirk Precision, Ltd. The chief advantage of this frame is low
cost. The frames can be die-cast in minutes...At this writing the frames are so new that there
has been little opportunity to ride or lifecycle-test them...The Mg used in the Kirk frames is
an alloy of Mg, Al and Zn...One [drawback of Mg] is its poor corrosion resistance, lower than
that of steel...<<

Certainly the Kirk Precision frames didn't become popular. I'm too lazy to do further research
(Google, etc).

I ordered some, corresponded for a year or two, and never received 'em. Were they _ever_ delivered
to stores?

I've seen one, a yellow MTB, several times here in Bergen. It's been a few months since I
saw it last.

Per D. Sørensen
--
"That is not dead which can eternal lie, And with strange aeons even death may die"

Abdul Alhazred

(Qui si parla Campagnolo) said:

Good question since magnesium burns quite well...think it's a lot like 'scamdium'
frames-essentially something else with a spot of magnesium...

I have a photo somewhere of a B-36 ("The Magnesium Overcast"😉 burning after a crash landing. The
blinding, white-hot light from the burning metal is something to see.

John Henderson, New York City, USA
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
"Let's roll!" -- Todd Beamer, 9/11/01 "After five and weekends" -- 711th SOS
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

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

Quoted message said:

These are starting to appear - Pinarello has one, among others. Anyone know anything about them
besides marketing lies? Alloyed? Durability? How are they welded?

They're cast, one big solid hunk of metal. I hear they're prone to cracking, but they're pretty
rare anyway.

More common were cast magnesium BMX wheels many years ago, before the molded plastic ones
became popular.

Matt O.

(Jon Isaacs) said:

Quoted message said:

I ordered some, corresponded for a year or two, and never received 'em. Were they _ever_ delivered
to stores?

They must have been. I saw one at a garage sale about 5 years ago, no cracks that I could see. The
guy wanted $5 for it but I passed, not my size....

jon isaacs

I find that highly unusual! Jon Isaccs passes on a $5.00 frame?

What is this world coming to? <g>

Sparhawk

Sparhawk said:

(Jon Isaacs) said:

They must have been. I saw one at a garage sale about 5 years ago, no cracks that I could see. The
guy wanted $5 for it but I passed, not my size....

I find that highly unusual! Jon Isaccs passes on a $5.00 frame?

What is this world coming to? <g>

Heck, it would be worth at LEAST $5 to see if I could light it!

Mark "I'd probably want to do it near a lake though" Hickey Habanero Cycles habcycles.comhabcycles.comOpen ↗
Home of the $695 ti frame

M-Gineering import & framebouw said:

A machinist who had worked at BRM told me only the swarf would catch fire (remove that wooden
lattice in front of the lathe before you start) and the lathe might go up in flames with it. When
the fire was extinquished (rush to the neighbour/builder for sacks of cement) the actual workpiece
would still be there.

I remember my 6th grade science teacher giving a demonstration of burning magnesium.

The school had just bought a nice new roll-around science table with burners, all sorts of neat
gadgets, and a smooth, formica top.

He put some magnesium scraps in a Pyrex container and torched them.

The Pyrex promptly exploded all over the room, leaving our poor bewildered science teacher to
watch the chunks of magnesium burning their way through his nice new formica table top. He stood
there with a sheepish look on his face holding a fire extinguisher, knowing it would do
absolutely no good.

Now THAT was a lesson learned (for him AND us)!

Mark Hickey Habanero Cycles habcycles.comhabcycles.comOpen ↗ Home of the $695 ti frame

"Mark Hickey" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

M-Gineering import & framebouw said:

A machinist who had worked at BRM told me only the swarf would catch fire (remove that wooden
lattice in front of the lathe before you start) and the lathe might go up in flames with it. When
the fire was extinquished (rush to the neighbour/builder for sacks of cement) the actual
workpiece would still be there.

I remember my 6th grade science teacher giving a demonstration of burning magnesium.

The school had just bought a nice new roll-around science table with burners, all sorts of neat
gadgets, and a smooth, formica top.

He put some magnesium scraps in a Pyrex container and torched them.

The Pyrex promptly exploded all over the room, leaving our poor bewildered science teacher to
watch the chunks of magnesium burning their way through his nice new formica table top. He stood
there with a sheepish look on his face holding a fire extinguisher, knowing it would do absolutely
no good.

Now THAT was a lesson learned (for him AND us)!

When I was a teenager I worked in a machine shop that made race car parts, among other things.
There were lots of magnesium shavings lying around, much like the strips science teachers use for
their demonstrations. We used to take piles of shavings out back and light it on fire with
welding torches. We even tried to light an old wheel once, without success (which was probably a
good thing).

Matt O.

Matt O'Toole said:

When I was a teenager I worked in a machine shop that made race car parts, among other things.
There were lots of magnesium shavings lying around, much like the strips science teachers use for
their demonstrations. We used to take piles of shavings out back and light it on fire with
welding torches. We even tried to light an old wheel once, without success (which was probably a
good thing).

That probably answered my question. I have this vision of getting into a sliding crash on pavement
with a magnesium bike - a few sparks at first, and then the frame ignites - woo hoo!

Maybe you just can't ignite them without unreasonable amounts of heat until they are cut into
shavings. Otherwise, I'd expect the mag auto wheels would torch from time to time. But say, in a
full-blown car fire, would you get enough heat? Or am I missing something?

Regards,
--
Mark Janeba remove antispam phrase in address to reply

"Mark Janeba" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

That probably answered my question. I have this vision of getting into a sliding crash on pavement
with a magnesium bike - a few sparks at first, and then the frame ignites - woo hoo!

Maybe you just can't ignite them without unreasonable amounts of heat until they are cut into
shavings. Otherwise, I'd expect the mag auto wheels would torch from time to time. But say, in a
full-blown car fire, would you get enough heat? Or am I missing something?

From www.magnesium.org :

"Magnesium can be ignited, upon which it will burn with a brilliant white light at a temperature of
about 2800°C. However, it is only magnesium vapor that will burn. Thus, the metal must be heated to
a temperature high enough to produce a sufficient quantity of vapor to support combustion. As a
practical matter, this means the metal must be melted. Pure magnesium melts at 650°C. Because the
heat conductivity of magnesium is high, all of a massive piece must be raised to the melting point
for the piece to burn freely. Thus it is very difficult to start a fire with a massive piece such
as a casting. Even if a torch is used to raise a part of the casting to the ignition temperature
and burning starts, it will cease when the torch is removed, by heat conduction to other parts of
the casting and consequent lowering of the temperature below the ignition temperature. On the other
hand, finely divided magnesium, such as some kinds of machining scrap, and very thin ribbon, cannot
conduct the heat away from a source and burning can be initiated with a match, which has a flame
temperature of about 900°C. Continuous burning of the chip or ribbon will be sustained after the
match is removed. Fire hazard is therefore principally associated with finely divided magnesium,
and is most apt to be encountered in machining or grinding operations, rather than in the service
of a part."

--
==================
Kraig Willett www.biketechreview.com
==================

"Kraig Willett" <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

From www.magnesium.org :

"Magnesium can be ignited, upon which it will burn with a brilliant white light at a temperature
of about 2800°C. However, it is only magnesium vapor that will burn. Thus, the metal must be
heated to a temperature high enough to produce a sufficient quantity of vapor to support
combustion. As a practical matter, this means the metal must be melted. Pure magnesium melts at
650°C. Because the heat conductivity of magnesium is high, all of a massive piece must be raised
to the melting point for the piece to burn freely. Thus it is very difficult to start a fire with
a massive piece such as a casting. Even if a torch is used to raise a part of the casting to the
ignition temperature and burning starts, it will cease when the torch is removed, by heat
conduction to other parts of the casting and consequent lowering of the temperature below the
ignition temperature. On the other hand, finely divided magnesium, such as some kinds of machining
scrap, and very thin ribbon, cannot conduct the heat away from a source and burning can be
initiated with a match, which has a flame temperature of about 900°C. Continuous burning of the
chip or ribbon will be sustained after the match is removed. Fire hazard is therefore principally
associated with finely divided magnesium, and is most apt to be encountered in machining or
grinding operations, rather than in the service of a part."

Attempt at burning a magnesium NeXT cube:

simson.netcubefire.htmlOpen ↗

"Mark Hickey" <[email hidden]> wrote in message

Quoted message said:

Heck, it would be worth at LEAST $5 to see if I could light it!

Mark "I'd probably want to do it near a lake though" Hickey Habanero Cycles

I don't think a lake would put it out. They had some magnesium flares go off on an Aircraftcarrier,
they burned through the decks, hull and then on towards the bottom of the ocean. Thats some realy
impressive stuff. By the way, titanium burns pretty good too.But is hard to start, I did it with
drill shavings.But, years ago some dummies set off a pretty good pile of it with an oxyacetelene
cutting torch, Titanium burns yellow-orange, vice magnesium, bright white-blue. Back to your
statement, I think I'd pay $20 just to burn it, but I'd do it in a sand pit. I like igniting
different metals to see what happens, and so do most people, if they like watching fireworks. len

Tom D said:

[email hidden] (Appkiller) wrote in message
news:<[email hidden]>...

Quoted message said:

These are starting to appear - Pinarello has one, among others. Anyone know anything about them
besides marketing lies? Alloyed? Durability? How are they welded?

Not that I am interested in purchasing one, just curious.

I don't know much, but they're not *that* new. I have a 1988 edition of Eugene Sloane's _Complete
Book of Bicycling_ that has an extended quote from Douglas Hayduk's _Bicycle Metallurgy for the
Cyclist_ (no date, but no later than 1988):

I have Hayduk's book (what happened to him?). It is the strangest book I own in that it is the only
book I've ever seen with the even pages on the right and the odd pages on the left. Weird. No Frank,
I'm not holding it upside down.

"Matt O'Toole" <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

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

Quoted message said:

These are starting to appear - Pinarello has one, among others. Anyone know anything about them
besides marketing lies? Alloyed? Durability? How are they welded?

They're cast, one big solid hunk of metal. I hear they're prone to cracking, but they're pretty
rare anyway.

More common were cast magnesium BMX wheels many years ago, before the molded plastic ones became
popular.

Matt O.

The Kirk magnesium frame was a cast frame, ugly like baboon. That was what, 15 years or so ago? TVM
had a contract to race them, but I don't know if they ever did. There is a new frame that claims to
me welded magnesium, but as Peter mentioned, it's probably mostly something else (aluminum?) with
some percentage of mag. alloyed with it.

Cast mag. is pretty common, RockShox lowers, Time pedal bodies, scary light stems, etc. I have had
mostly good luck with Time and R-S stuff, but the new 100ish gram stems give me the creeps. -Jim

"Meccanico di Bici" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

but the new 100ish gram stems give me the creeps.

Don't take this the wrong way, but, which ones and why?

--
==================
Kraig Willett www.biketechreview.com
==================

"Kraig Willett" <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

"Meccanico di Bici" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

but the new 100ish gram stems give me the creeps.

Don't take this the wrong way, but, which ones and why?

Take what the wrong way? No worries, this is all just opinions, eh? Anyway, we recently put an ITM
The Stem on a bike, and maybe it's irrational, but it just seemed too light. You know how you expect
certain things to act or feel a certain way? When I pulled the stem out of the box, it just felt too
light. Also, mag. has never been the best thing to put threads into, add Ti bolts and it's begging
to strip or gaul. The torque spec for the stem was like 6Nm, not very tight.

Now, a couple years back I used an Easton mag. mtb stem for a few months, and had no problems.
However, it wasn't particularly light and I put steel bolts in it slathered in antiseize. As a just
<200lb guy who likes to ride lots of dirt roads, I'm gonna stick to more robust aluminum and steel
stems, the peace of mind is worth a few extra grams to me. Cheers. --Jim

"Meccanico di Bici" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Take what the wrong way? No worries, this is all just opinions, eh? Anyway, we recently put an ITM
The Stem on a bike, and maybe it's irrational, but it just seemed too light.

You and I think similarly. I went one step further, though, and decided to find out for myself by
conducting an actual fatigue test. Were you afraid that that stem might wind up like this:

tinyurl.com4wchOpen ↗ ?

Lots of the others I tested wound up the same way. Some were better than others.

--
==================
Kraig Willett www.biketechreview.com
==================

Kraig Willett said:

You and I think similarly. I went one step further, though, and decided to find out for myself by
conducting an actual fatigue test. Were you afraid that that stem might wind up like this:

tinyurl.com4wchOpen ↗ ?

Ouch. Notice that that stem was also anodized. Wonder if that was a contributing factor.

--

David L. Johnson

__o | When you are up to your ass in alligators, it's hard to remember _`\(,_ | that your initial
objective was to drain the swamp. -- LBJ (_)/ (_) |

"David L. Johnson >" <David L. Johnson <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Kraig Willett said:

You and I think similarly. I went one step further, though, and decided to find out for myself
by conducting an actual fatigue test. Were you afraid that that stem might wind up like this:

tinyurl.com4wchOpen ↗ ?

Ouch. Notice that that stem was also anodized. Wonder if that was a contributing factor.

Arrggh! Let's not go there again. ;- )

The stem depicted is magnesium, so it has a special coating, but is not anodized. The other stems
that I tested were aluminum and were cosmetic anodized. I find there to be other important things in
the overall design one should consider rather than simply focusing on the final cosmetic finishing
(it is a factor, yes, but one of many) - wall thickness, extension geometry, mfg method, material
selection, etc. are better _indicators_ of fatigue performance for stems in my experience.

--
==================
Kraig Willett www.biketechreview.com
==================

"Kraig Willett" <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

"Meccanico di Bici" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Take what the wrong way? No worries, this is all just opinions, eh? Anyway, we recently put an
ITM The Stem on a bike, and maybe it's irrational, but it just seemed too light.

You and I think similarly. I went one step further, though, and decided to find out for myself by
conducting an actual fatigue test. Were you afraid that that stem might wind up like this:

tinyurl.com4wchOpen ↗ ?

Lots of the others I tested wound up the same way. Some were better than others.

Yeouch! Without divulging to much detail, did that stem fail under what would be considered "normal"
amounts of load, or did you really wail on it? Did you test Ritchey WCS or Pro stems? (I'd check out
your site deeper, but all those numbers and engineering-speak is Greek to me!) They seem like good
stems for the money, light but not scary so. Not sure who makes them, maybe Kalloy? I have a WCS on
my cross bike, a custom fillet brazed steel stem on my road bike, and a Race Face SyStem on my mtb.
Any imminent doom in my future? --Jim --Jim