View Single Post
  #79  
Old July 12th 18, 04:54 PM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 4,018
Default drill/tap in frames

On Thu, 12 Jul 2018 00:41:36 -0700, John B. Slocomb
wrote:
Then, of course, the question arises as to what is a significant
difference? Someone mentioned a bit ago about deciding that a TIG
welded frame joint was strong enough to work, ignoring that a properly
made sweated joint is always much stronger.

Bicycle tubes and thus frames, are not all of the same strength.
Columbus XCR material has an ultimate tinsel strength of 1350 MPa
(195,800 PSI), Nobium is 1050 (152,289 PSI) and 25CRMO4 is 80 MPa
(116,030 PSI).

One can only speculate on the effects of drilling, oh say, a quarter
inch rivnut hole in a (approximately) 200,000 psi strength tube and
doing the same thing in a tube roughly half the strength?


Good point. I plan to use the weakest possible steel tubing as
excavated from the junk pile. I think it unlikely that I'll find any
manner of exotic metals or even double butted tubing. At this time,
all I care about is that the two tubes are reasonably identical.

Tinsel strength?

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Ads
 

Home - Home - Home - Home - Home