Hi Folks, Let me start off by saying that I now use a Ney
computer driven oven and have for the past 12 years, BUT for
the 18 or so years before that I used the standard "Dial"
furnace with a pyrometer. These ovens have a calibration screw.
All you need to do is use furnace calibration pellets! Put one
in the center of your furnace and when it melts the oven is at
the temp at which that pellet melts! You then adjust the
pyrometer and voila’ when your pyrometer says 1000 deg.F., That
is exactly (or close enough) the temperature of the furnace!
They make these pellets in several melting temperatures. You
can get them from a dental lab supply house, or call the furnace
manufacturer. By the way, my backup furnace is a Jelenko brand
that is so old that the controller uses an abacus! If you do
enough casting all you have to do is look at the ‘glow’ of the
furnace to get a good idea of the temperature.
N.R.A. Endowment &
in all disciplines
Certified Illinois D.N.R.
Hunter Ed, Instructor