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titanium junkie
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Discussion Starter · #1 ·
Why is butted titanium tubing better besides being lighter? Do they (butted) ride better? Does a butted tube oscillate differently than a straight gage tube? It seems like these titanium double butted and triple butted tubes have a very thin middle section and can be damaged easier from denting, etc. and wondering if the weight saving is worthy.

From reading, Reynolds makes their butted tubing from the drawing stage with dies and mandrels while others butt their tubing by machining and grinding. Which is a preferred butting method? Since most of these tubes are about a .030” thick, how can they precisely remove material in the middle section of a tube? Would the thickness become uneven if the cutting or butting tool is being slight being off center?

Please enlighten me!
 

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Probably do the grinding with a centerless grinder. The thinner section probably does dent easier than straight tubing but remember Ti has a high elongation, if we're talking about 3/2.5 tubing. On the other hand, the 6/4 tubing doesn't have as much elongation so it probably dent more easily than the 3/2.5 tubing.
 

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titanium junkie
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Discussion Starter · #3 ·
Thanks

dlbcx said:
Probably do the grinding with a centerless grinder. The thinner section probably does dent easier than straight tubing but remember Ti has a high elongation, if we're talking about 3/2.5 tubing. On the other hand, the 6/4 tubing doesn't have as much elongation so it probably dent more easily than the 3/2.5 tubing.
Is that mean that the butted section does not have a uniform thickness throughout? What is the best way to fix a ti dent? Can it be vacuum pulled?
 

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I think the centerless grind process can maintain, around .005 in., in profile tolerance.
As far as dents, trying to pull dent out may induce a larger stress riser, which could cause a crack to occur. I would have to look at a spec sheet for Ti but I would guess that all of the cold working steps would occur while the tubing is an annealed condition since the cold work will increase the tensile strength.
 
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