[Harry Bloomfield[_3_]]

Could someone kindly provide me with the figures for the loading at
which a 6mm ordinary mild steel rod will begin to stretch and one at
which it will break please, assuming room temperature? An answer in
kilogrammes would be good, just to settle an argument.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

[John Williamson]

Harry Bloomfield wrote:
Could someone kindly provide me with the figures for the loading at
which a 6mm ordinary mild steel rod will begin to stretch and one at
which it will break please, assuming room temperature? An answer in
kilogrammes would be good, just to settle an argument.

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. A lot depends
on the end fastenings, though, as welding it to something will have an
unpredictable result on the strength of the bit affected by heat, and
the same goes for ultimate srength. Cutting a thread so you can tighten
it up with a nut will reduce the strength by a lot, depending on the
thread form. Strongest is hot rolled Whitworth, as it shouldn't have the
sharp, stress raising, corners of a cut thread.

--
Tciao for Now!

John.

[Harry Bloomfield[_3_]]

It happens that John Williamson formulated :
Harry Bloomfield wrote:
Could someone kindly provide me with the figures for the loading at which a
6mm ordinary mild steel rod will begin to stretch and one at which it will
break please, assuming room temperature? An answer in kilogrammes would be
good, just to settle an argument.

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. A lot depends on the
end fastenings, though, as welding it to something will have an unpredictable
result on the strength of the bit affected by heat, and the same goes for
ultimate srength. Cutting a thread so you can tighten it up with a nut will
reduce the strength by a lot, depending on the thread form. Strongest is hot
rolled Whitworth, as it shouldn't have the sharp, stress raising, corners of
a cut thread.

Brilliant, thanks exactly what I needed.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

[ARWadsworth]

Harry Bloomfield wrote:
Could someone kindly provide me with the figures for the loading at
which a 6mm ordinary mild steel rod will begin to stretch and one at
which it will break please, assuming room temperature? An answer in
kilogrammes would be good,

just to settle an argument.

Fallen out with SWMBO:-)?

--
Adam

[Harry Bloomfield[_3_]]

ARWadsworth wrote on 29/09/2011 :
Harry Bloomfield wrote:
Could someone kindly provide me with the figures for the loading at
which a 6mm ordinary mild steel rod will begin to stretch and one at
which it will break please, assuming room temperature? An answer in
kilogrammes would be good,

just to settle an argument.

Fallen out with SWMBO:-)?

Not his time :-)

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

[Richard[_10_]]

"Harry Bloomfield" wrote in message
. uk...
ARWadsworth wrote on 29/09/2011 :
Harry Bloomfield wrote:
Could someone kindly provide me with the figures for the loading at
which a 6mm ordinary mild steel rod will begin to stretch and one at
which it will break please, assuming room temperature? An answer in
kilogrammes would be good,

just to settle an argument.

Fallen out with SWMBO:-)?

Not his time :-)

Your typo, or maybe HWMBO?
;-)


--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

[Harry Bloomfield[_3_]]

Richard explained on 29/09/2011 :
"Harry Bloomfield" wrote in message
. uk...
ARWadsworth wrote on 29/09/2011 :
Harry Bloomfield wrote:
Could someone kindly provide me with the figures for the loading at
which a 6mm ordinary mild steel rod will begin to stretch and one at
which it will break please, assuming room temperature? An answer in
kilogrammes would be good,

just to settle an argument.

Fallen out with SWMBO:-)?

Not his time :-)

Your typo, or maybe HWMBO?
;-)

My wireless keyboard sometimes misses a typed character.

What I typed was 'Not this time :-)'

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

[Tony Bryer[_3_]]

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.

--
Tony Bryer, Greentram: 'Software to build on',
Melbourne, Australia www.greentram.com

[John Williamson]

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.

--
Tciao for Now!

John.

[The Natural Philosopher[_2_]]

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.

[John Williamson]

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.

--
Tciao for Now!

John.

[The Natural Philosopher[_2_]]

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..