View Single Post
  #6   Report Post  
MikeMandaville
 
Posts: n/a
Default


Richard J Kinch wrote: MikeMandaville writes:

What, specifically, did you find to be difficult or expensive?


Not easy: making the burner, the refractory, the crucible, the molds.

Just
took a while. Something you'd do either for fun trying, or because

you had
no other way.


Hello again, Richard.

Sorry I took so long to respond. I actually, didn't even realize that
you had answered my post. When you say "making the burner", I am
assuming that you were firing with propane, since that's what most of
the Gingery boys seem to do. I intend to fire with charcoal myself.
Actually, I plan on making my own charcoal as well, by the indirect
method, and I will be burning the emissions to make the process
self-perpetuating, once the oven is hot.

Since I am able to purchase genuine powderized fireclay locally, making
the refractory will be easy for me. This is something which would have
surprised even Dave Gingery himself, since he mentions in the shaper
book, 1998 edition, page twenty-one, paragraph seven, "I was surprised
to learn that fire clay could not be found in any city in the U. S.

So far I have managed to collect about a half-dozen iron or steel pots
of various sizes. The biggest one is a one-gallon cast-iron pot which
is made by Lodge, and which cost me about twenty dollars at Academy
Surplus. I might as well go for broke, since I would rather be casting
iron anyway.

For making the molds, I recently purchased a two-hundred-pound capacity
plastic sandbox at Toys 'R' Us for sixty dollars. I bought it because
of the tight-fitting lid, which will keep the moisture in, and the cats
out. I still need to build a bench for it.

Not cheap: real refractory, real crucible. The do-it-yourself

recipes sort
of work, but the results don't last, and the real stuff (like a

graphite
crucible) are expensive.


It looks like you purchased your refractory pre-mixed, in which case, I
can see that it cost you more than you would have spent otherwise. My
local supplier, by the way, ships out of state, though I suppose that
the shipping would probably cost more than the clay.

A crucuble would probably stand up to the heat better than an iron pot
will, I imagine. I plan on staying with the iron pots, though I expect
them to wear out sooner than the crucibles would.

I figured the fuel costs amounted to about what you would pay for
dimensional aluminum of the same mass, so to be economical, castings

have
to be things that "have to be" cast, not just turning free scrap into


machinable stock.


Since I plan on making my own charcoal from scrap wood, after I build
the oven to make my charcoal, I suppose that my basic cost will be the
gasoline which it will take for me to drive around scrounging up my
wood, and the time which it will take me to cook it.

Hazards: molten metal, airborne refractory fibers or dust.


I agree with you about the refractory fibers. I purchased some kaowool
awhile back, but have decided not to use it. It is really some nasty
stuff.

Again, I've enjoyed the experimentation. It's just not the case that

I
would be firing up the foundry now and then because I happened to be

out of
some size of machinable stock.


For me, melting aluminum will be something which will keep me happy
until I have built up a large enough stockpile of home-made charcoal
briquettes to give me a satisfactory "critical mass" for melting iron.
I will need to discover what this critical mass is by experimentation,
but I am guessing that I will need to have enough briquettes to supply
a cupola of about fourteen inches in bore diameter.

Mike Mandaville
in the "hill country", just west of Austin