could it be that the titanium shiftknobs are not real titanium?
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From: boulder
[QUOTE]Originally posted by malachi
[B]on a side note - the *primary* reason that Ti bike frames are so damned expensive is not material cost. building frames from Ti is *very* (VERY) difficult and very (*VERY*) unforgiving of any failure or error or deviation). domestic, russian, japanese, european... tube set source is basically a fractional change in cost.
a little background... i used to race (crit and time trial for the most part). one of the other riders on the team ended up as a senior frame builder for Fat City. after the sale/implosion there, he went to Merlin (one of the best Ti fabricators out there). since then i've sat through some truly epic discourses on the difficulties of fabricating with Ti.
[B]on a side note - the *primary* reason that Ti bike frames are so damned expensive is not material cost. building frames from Ti is *very* (VERY) difficult and very (*VERY*) unforgiving of any failure or error or deviation). domestic, russian, japanese, european... tube set source is basically a fractional change in cost.
a little background... i used to race (crit and time trial for the most part). one of the other riders on the team ended up as a senior frame builder for Fat City. after the sale/implosion there, he went to Merlin (one of the best Ti fabricators out there). since then i've sat through some truly epic discourses on the difficulties of fabricating with Ti.
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From: SF
sorry for the confusion, didn't race for Merlin - one of the other team riders - and a friend of mine - (eventually) ended up working for Merlin. afraid i don't know carol.
while it's true that top-end Ti tubing sets are *dramatically* more expensive than, say, cheap steel tubing, it's still a fractional cost as compared to the frame-making costs. skilled labor (especially niche skill like this) is almost always going to be the big cost, but the equipment cost is also high. and you don't want to skimp on the quality of the labor given the potential costs of screwing up.
while it's true that top-end Ti tubing sets are *dramatically* more expensive than, say, cheap steel tubing, it's still a fractional cost as compared to the frame-making costs. skilled labor (especially niche skill like this) is almost always going to be the big cost, but the equipment cost is also high. and you don't want to skimp on the quality of the labor given the potential costs of screwing up.
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From: Portola Valley
KenS2k:
Aren't you thinking of Magnesium?
Last I heard, Ti doesn't have particularly pyrotechnic properties.
As far as TIG (Tungsten / Inert Gas) welding is concerned, that is how all these Ti bikes we are talking about are made so maybe there was something not inert about the IG, (inert gas) part of your welder. Maybe someone hooked up the oxygen bottle
.
As for necessarily being billet, I think you are wrong there. Ferrari's and NSX's I believe have forged Ti con-rods. Basically, any metal that can be deformed can be forged. It's cold work properties determine whether it is worth doing. Ti does work harden so it is of value. As for sinterising... I just don't remember if it is done, but any metal that melts should be able to be sinterised. The only question is whether the pressure required is so great that the costs don't work out.
As for the Magnesium alloy I'm guessing you are talking about, what you describe can happen. Mg castings despite low concentrations of Mg can flame under certain conditions such as welding. Pure Mg (90 +%) is very very volatile - especially in contact with water.
A funny story. At the foundry in my previous company, we had a prankster steal a lump of pure mg alloying ingot. He dropped it in the crapper and flushed. There were 7 crappers in a row, and this stuff only blew when it reached stall #4 where someone was in the middle of a dump. It blew the throne off the floor. Nobody was hurt, so it was funny... but I bet that guy never sits down for a good one anymore.
Oh... the S2000 connection... it was a very fast ride but the seat wasn't as good as ours.
Dan
Aren't you thinking of Magnesium?
Last I heard, Ti doesn't have particularly pyrotechnic properties.
As far as TIG (Tungsten / Inert Gas) welding is concerned, that is how all these Ti bikes we are talking about are made so maybe there was something not inert about the IG, (inert gas) part of your welder. Maybe someone hooked up the oxygen bottle
.As for necessarily being billet, I think you are wrong there. Ferrari's and NSX's I believe have forged Ti con-rods. Basically, any metal that can be deformed can be forged. It's cold work properties determine whether it is worth doing. Ti does work harden so it is of value. As for sinterising... I just don't remember if it is done, but any metal that melts should be able to be sinterised. The only question is whether the pressure required is so great that the costs don't work out.
As for the Magnesium alloy I'm guessing you are talking about, what you describe can happen. Mg castings despite low concentrations of Mg can flame under certain conditions such as welding. Pure Mg (90 +%) is very very volatile - especially in contact with water.
A funny story. At the foundry in my previous company, we had a prankster steal a lump of pure mg alloying ingot. He dropped it in the crapper and flushed. There were 7 crappers in a row, and this stuff only blew when it reached stall #4 where someone was in the middle of a dump. It blew the throne off the floor. Nobody was hurt, so it was funny... but I bet that guy never sits down for a good one anymore.
Oh... the S2000 connection... it was a very fast ride but the seat wasn't as good as ours.
Dan
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If you ever have the opportunity, while camping on a cold night and drinking beers, throw a volkswagon bug engine on the fire. When the magnesium block ignites (takes a while), you have a very hot and bright fire for quite a while! Not much is left in the morning. Also, it is helpful to have welding goggles if you want to actually look at the fire too.
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From: Portola Valley
Bobway...
You are so right!
We actually used to buy junked VW engines to use for alloying the crap aluminum alloys to make windows and irrigation tube. The transmission housings are even better!
Dan
You are so right!
We actually used to buy junked VW engines to use for alloying the crap aluminum alloys to make windows and irrigation tube. The transmission housings are even better!
Dan