|Good article on frame materials.||undertrained|
Oct 8, 2003 12:06 PM
|And here's more on the author...||Chicago_Steve|
Oct 8, 2003 1:18 PM
Oct 8, 2003 3:42 PM
|Thanks for sharing it with us.|
|A bit dated?||filtersweep|
Oct 9, 2003 3:44 AM
|The 90210 reference?
I doubt there is a pure magnesium frame out there... the writer presents us with this little "gem":
"One of the intangible benefits of magnesium is that if you need to start a fire for some reason, just scrape some flakes off your dropouts, and light them up. They'll easily burn. For the mini- Hindenburg effect, just add water. The oxygen and hydrogen in the water disassociate, and party down with help from the magnesium. By the way, titanium does the same thing, but it's a little harder to get it started. "
BTW- my car has magnesium rims... they are holding up just fine.
|A bit dated?||Anonymous Gerbil|
Oct 9, 2003 5:02 AM
|Look here for such a frame -
|Your point is?||filtersweep|
Oct 9, 2003 5:30 AM
|Don't you think this is an alloy? As a "metal" magnesium is really a salt. Sure you can have fun rubbing off an oxidized layer and burning a bare metal shaving, but it will take more than a match, and adding water won't provide much excitement unless it is already burning at +5000 degrees (when the hydrogen and oxygen can separate). Maybe you could make a shaving from a fork drop-out "fizz" if you pour vinegar on it ;)
It is obvious that pure magnesium has no structural use.
Even while welding an magnesium alloy, the risk of ignition is rather low. Keep in mind that some Volkswagen engine blocks were made of magnesium alloy.
The dated part I was referring to was the 90210 reference. Magnesium is practically a footnote to the article.
|Another interesting point in the article||Chicago_Steve|
Oct 9, 2003 6:06 AM
|He talks about Lithium Aluminum alloys towards the end of the article...
Just recently Reynolds released their X-100 LiAl tubing. Surprisingly, Jamis is the only mfr I know of that is using this tubing... Here's the marketing hype...
Lithium, the world's lightest metallic element, increases both the strength and stiffness of aluminum when alloyed at optimum quantities. Like Reynolds 853 steel, X-100 is a "precipitation hardening" alloy with the fine grain size formation that promotes high strength and fatigue life. However, unlike 853, X-100 does require a specific frame heat-treatment process to realise its'potential benefits.
Steve (my next bike will probably be steel...)
|no. simple chemistry.||weatherx|
Oct 9, 2003 9:10 AM
|it's about the area of reaction. flakes and powders have a lot more area than a chunk of the same mass. a chunk of magnesium won't burn readily, but flakes and powders will.
some of the weight weenie guys in mtbr actually have done this. they dremeled the lower tubes of their suspension forks (not often made from magnesium and its alloys) and burnt the powder.