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Wandered over to the local Scrap & Steel yard and bought 9 lbs. of
Aluminium round stock, solid & 1/4" wall thicknesses in diameters to
2.5".

Question... is it normal to find that stuff is out of round as much as
0.010" INSIDE AND OUT? <lots of skip to cut the high parts down>

Incidently....They don't need a lathe to "Gouge"!!....$34.00

Had fun turning my first inside stock to 1.25" + a tad because I was
turning it too slow...(being too careful). :-) Larry

To answer your question about the out of round condition in metal stock,
there are two popular methods of manufacturing round stock, the first is
"Hot Rolling" where steel or aluminum sheet is heated and rolled at
temperature into a solid bar or tube. The second method is "Cold Rolling",
where the steel or aluminum sheet is rolled at room temperature under
pressure forming the solid bar or tube. The out of round condition you are
seeing is the overlap of the end of the sheet. Depending on the thickness of
the sheet and the method used, this will determine how much out of round you
see.
Skydoc_17

"Round" is in eye of beholder..."a commercial standard" might be anything
aproximating
a circular shape more than a square or hexagon...as to prices...scrap
aluminum is
a valuable material because of the vast amount of electricity required to
reduce it
from ore...for last few years demand has exceeded production capacity...if
your recycler allows you access to look around you are fortunate considering
liability issues...that said
if you can shop around you may find a better price or maybe not...I am
fortunate enough
to be allowed to look and sometimes I find an old outboard motor to tinker
with as well
as an occasional piece of stock...if a local company mills aluminum or brass
their rejects
get recycled and you may be fortunate...remember your recycler is a business
just like
any other and they are entitled to try to make as much profit as they
can...you can buy
or not buy as your interests dictate...if you don't pay an excessive price
and no one
else does the price will go down...if someone else buys at a price you
reject...MAYBE...
the price was a fair market price (even if seemingly a gouge)

noskyhere wrote:

Wandered over to the local Scrap & Steel yard and bought 9 lbs. of
Aluminium round stock, solid & 1/4" wall thicknesses in diameters to
2.5".
Question... is it normal to find that stuff is out of round as much as
0.010" INSIDE AND OUT? <lots of skip to cut the high parts down>

Aluminum tube, except in large sizes, is extruded. it comes out looking like
spaghetti or toothpaste (ie. wavy). They pull it to straighten it. As the internal
stresses are relieved, it warps, and is no longer as round as the die made it.

.010" seems pretty minor.

Jon