On Jul 8, 6:04*am, MajorOz wrote:
On Jul 7, 4:44*pm, BJ Conner wrote:





On Jul 7, 9:57*am, MajorOz wrote:

On Jul 7, 9:28*am, BJConner wrote:

On Jul 6, 12:07*pm, MajorOz wrote:

On Jul 6, 6:15*am, riverman wrote:

On Jul 6, 5:18*am, MajorOz wrote:

On Jul 5, 7:36*pm, riverman wrote:

On Jul 5, 3:27*pm, rw wrote:

On 7/5/10 7:08 AM, rw wrote:

On 7/5/10 5:12 AM, riverman wrote:

I'm not convinced that heat expands the radius of the hole, as in a
photographic enlargement. Objects expand around their physical mass.
There is a classic physics demonstration with a steel ring and a steel
ball where you heat the ring and find that the ball will not fit
through the ring. So, just as the hole in a rising donut (or bagel is
more like it) gets smaller, I would expect the hole to get smaller if
you heated the female section. But countereffecting that would be that
the circumference of the torus would also increase. Maybe there is
some sort of ratio of circumference to torus thickness where the hole
actually does not change....I don't know. But the action of the female
end of a ferrule is a very thought-provoking thing.

http://physics.bu.edu/~duffy/py105/Temperature.html

BTW, I think you're misremembering the ring and ball experiment. It
actually demonstrates just what I (and others) have been saying about
thermal expansion of a hole.

--
Cut "to the chase" for my email address.

You're right. I just saw this on youTubehttp://www.youtube.com/watch?v=V0ETKRz2UCA

So OK, *the hole gets bigger when the female end is heated, however
the male end gets bigger also. Which gets bigger faster?

Read my post. *It explains what and why.

oz

Err, which one, Oz? The one where it says "can't guarantee anything,
but that is the theory" or the one that says "disregard my response"?

:-)

--riverman

They are both sincere (in context), but the one I had in mind was that
the metal will expand or contract with temperature change based on the
original (pick your starting point) temp.

However, they all will change at percentage of the starting size
(assuming identical composition).

To wit: if expansion is X %, a three inch circle will expand to 3 in
+ *X% of three inches, while the little bit less than three inches
will expand to LBLT3in. + X% of LBLT3in, resulting in an ever widening
gap as temp increases.

In sum: the gap between inside and outside widens with increasing
temperature.

Ideally, of course, fill the (hopefully) hollow inside one with water,
freeze the whole mess, then zap the outside QUICKLY with heat and slip
them apart. Kinda like baked Alaska.

Works only with metal. *Obviously not with graphite.

In a sever case in the past of irretrievably stuck graphite ferrules,
I just wound up with a rod five inches shorter.
( Solution left as an exercise -- hint: it involved a jeweler's saw )

cheers

oz- Hide quoted text -

- Show quoted text -

"In sum: the gap between inside and outside widens with increasing
temperature. "
Maby it does in the Russian navy but not anywhere else in the world..

Although I have been aboard Russian (actually Soviet) ships, my
engineering degrees are from US schools.

Maby (sic) your experience is different ?

cheers

oz- Hide quoted text -

- Show quoted text -

Your right. *I was thinking about trigger guard assemblies or
something.
I had to go back and thing about a sections of RR track- one 100' long
and one 101' . * *The units of change are in/in/degree IF you bend
them into circles the circumference of the bigger circle grows more
and the radius becomes greater.
.

There is the old chestnut about a metal strap around a barrel. *Cut
the strap and insert a piece 10 ft long and then re-make it into a
circle. *Lay it down, so that the barrel is centered in the "hoop".
Distance between barrel and hoop is a bit over 19 inches.

Now put a metal strap around the earth. *Increase, as above, the
length by 10 feet.
How "high" above the ground will it then be ? * * * * As before, about
19 inches.

Around a marble? *19 inches.

Irritating, but that's the way it is.

cheers

oz

My favorite version of that goes the other way; how much do you have
to add to a strap that surrounds the earth in order to raise it one
inch off the ground? Turns out that its the same amount you have to
add to your belt if you need to wrap it around a jacket that is one
inch thick, or around the universe if it grows one inch in radius.

--riverman