On 7/12/2018 3:01 AM, sms wrote:
On 7/11/2018 8:43 PM, Jeff Liebermann wrote:
On Wed, 11 Jul 2018 17:24:40 -0400, Frank Krygowski
wrote:


Exactly. Strong enough is strong enough.

OK, so let's pretend that the tube with the Rivnut bent at 10% less
tension.Â* Is that "strong enough"?Â* There's no way to tell without the
original design calculations, or reverse engineering the frame with an
FEA model.Â* Too bad Autodesk killed their online ForceEffect web app.
http://blogs.autodesk.com/inventor/2017/01/17/autodesk-forceeffect-family-retirement/

I think I could have modeled the problem using the program.

It's a bad experiment because it doesn't take into account whether or
not the hole was properly drilled and the Rivnut properly installed. You
also have to do it with the same aluminum tubing used on a bicycle
frame, but even then it isn't accurate because there's no way to factor
in metal fatigue which isn't an issue as much in steel as it is in
aluminum.

Remember, just because you can often get away with doing a really stupid
thing, it doesn't mean that you should still do it.

Remember, just because one person declares a practice to be stupid, it
doesn't mean the practice really is stupid.

In fact, if the practice (like the use of Rivnuts) is generally very
successful, the stupidity probably lies elsewhere.

--
- Frank Krygowski