RE:re:Re: cast iron

I've been surfing some of the solar collector sites and I think you
guys have a prety good idea here.

If you put your part 'under glass' the sun will heat it like a car,
to 60°F - 70° - or maybe even 80° in January. Then, with a timer or
some such instrument, you could open the door and let in the cold
night air. It'll take a few hours to get the part warm all the way
through and it'll freeze at night. Summer/winter in a day. You
could probably season a part in one winter that way.

--- In CAD_CAM_EDM_DRO@y..., "James Owens" <wotisname@l...> wrote:
> Hi Ballendo,
>
> I must say that most of the castings that I machine are for high
and very
> high precision and I tend not to want to rush and ruin.
>
> > What about the 'accelerated' aging? I didn't mean to imply that
the
> > box (refrigerator/icebox) would get very hot. It seems that
> > if 'natural aging', which as you said, relies on the weather, will
> > work well; then a faster Day/ night cycle might be created.
Something
> > based on the time for the casting(s) to reach the high, then the
low
> > temp. (which would save time as long as the castings weren't so
large
> > as to take a "days' worth" of time to cycle)
>
> With weathering in this country we have a fluctuation in
temperature in the
> order of 5-10c in a twenty four hour period. On top of that winter
average
> temperatures can go as low as -10c with the summer ones up as far
as 30c.
> The use of "Green House" ageing speeds up the process from over a
year to
> three months. I cannot comment if your idea will work, as I haven't
tried
> it, but I wonder if there would be enough time between hot and cold
cycles
> on the thicker sections to make the expense and, possibly, shorter
time
> worth while.
>
> In short putting the castings under glass and using the sun is
virtually
> free. A refrigeration and heating unit would cost a lot to run.
>
> > I used to work extensively with wood, and the equivalent there
> > is 'air dried' vs. 'kiln dried'. The Kiln group always
said, "There's
> > NO difference, IF the kiln process is done correctly!" But using
> > hand tools, I could ALWAYS tell the difference. For SOME things
the
> > difference 'mattered'; for many things it did not.
>
> I too notice the difference as most of my woodwork these days is
for pattern
> making, as I am trying to do this with CNC, this is the reason I
looked and
> found this list.
>
> > So maybe the BEST procedure is Shake, Bake, AND age! But what
about
> > the "good enough" that many of us will be looking for?
>
> I can see that a combination of sonic ageing and weathering may
well get you
> the results you require but until it is proved I'll go with my way
of
> working certainly for my one off irreplaceable castings.
>
> Terry