[SEL] Pouring castings at the Tod Engine Works Class.

[Arnie Fero]

Hi Curt,

While its unlikely that I'll ever do any castings, I am greatly enjoying
these "experience" posts.  When you look at large cast iron parts like
those that comprise the Tod engine and imagine that castings of this size
and much larger were routine day-to-day operations, you have to ask
yourself what would it take to do that today?  How many "tricks of the
trade" that were never written down, but were passed on man to man in the
foundary, have been lost and would need to be rediscovered.  Keep up the
good work and keep the stories coming.

See ya,  Arnie

On Tue, 25 Apr 2006, Curt wrote:

> Glad you enjoyed. Yes the green sand is reused. Core sand is not as it
> is a catalyzed sand (linseed oil and some catalyst).
> Yes the muller breaks up clods of used sand and mixes in the water and
> clay you add to give the correct consistency.
> Proper green sand will stay in a shape that you squeeze with your hand.
> Too little water and clay and the mold falls apart. Too much water and
> the castings will have too much porosity/gas defects.
> You'll find this interesting. I designed the core print on our
> patterns/coreboxes to be the same length as the distance the core is
> cantilevered into the mold. This worked well for 2 of the 3 molds.
> However, on the 3HP Hercules piston, the weight of the cantilevered
> portion of the core was greater than the weight of the core print. This
> resulted in a tipping of the core in the cavity, rather than resting
> neatly in place. I thought I had screwed that pattern up! Clever Rick
> calmly broke off a piece of Styrofoam and placed it in the mold to
> support the core long enough to set the cope flask on. The Styrofoam
> vaporizes instantly when the metal hits it. I thought this was a pretty
> clever solution to one of those "oh shit" moments.