DANMAS@aol.com wrote:
> Chris:
> =
> You may be right - it's been many years since I had a materials class,
and I
> didn't pay a whole lot of attention then - but I have always thought
about it
> a litttle differently.
Well, it was more than a few years ago that I had the class, so I=
may
have gotten it mixed up...
> maybe I will go bore a hole in a piece of metal, toss it in the freezer=
,
and
> see if the fit to a bolt which has been kept at room temperature is
looser or
> tighter (hopefully, someone else will beat me to it and report back to
the
> group so I won't have to!).
Chris Chandler wrote:
<Let me know the results! You've got me wondering now too. Of course,
there's also the (possible) material differences between pistons and
rings and blocks to consider also.>
When materials get cold, ice is an exception, they shrink. The atoms
occupy less space due to their decreased activity. Holes in material
become larger. A piece of material, say a piston, becomes smaller
therefore increased clearances.
Regards,
Michael.
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