John Williamson wrote:
The Natural Philosopher wrote:
John Williamson wrote:
Tony Bryer wrote:
On Thu, 29 Sep 2011 18:27:20 +0100 John Williamson wrote :
It will start stretching under *any* load, linear(ish) up to about
15% at about four tons, and it will snap at just over 5 tons.

The figure I have for S235 mild steel is a yield strength of
460N/mm2. 6mm rod has an area of 28.3mm2 x 460/1000 = 13kN, or 1.33
tonnes.

searches Finds missing divide by four under flap of envelope.


That seems very weak for 6mm rod.

68,300 psi breaking srain for mild steel, divide by four squared, then
by pi, then by 4.

1.398 imperial tons. Then knock half off for the thread weakening it, or
the heat affecting the metal near the welds. If I use a reasonably long
spanner, I can easily snap a quarter inch diameter bolt. It's how I
normally get the exhaust off the Land Rover.

yebbut that's shear strength, not tensile strength and in torsion which
is odd in that the center plays little part.

Pretty sure i've lifted (most of) a car on a single 1/4" rod in part of
a pulley block. Mind you it did deform a bit..