Temperature and Rate Conversion
Understanding the difference between a
temperature conversion and a rate conversion is vital for anyone who
wishes to convert firing schedules from Fahrenheit to Celsius (or
vice versa).
A temperature conversion is a simple
conversion from a temperature in one scale to a temperature in the
other. 200 degrees Fahrenheit (F), for example, is just over
93 degrees Celsius (C), while 200 degrees C is 392 F.
These conversions can be confirmed with the
topmost of the two calculators on this page. Most online
calculators are temperature converters; they work well when making
straightforward temperature conversions from one scale to another.
But they aren't always the best tool to use for converting firing
schedules for glass.
Instead, it is important to
recognize that a different formula needs to be used when converting rates
of temperature change. Many firing schedules use rates of
temperature change (i.e., increase at 200 degrees per hour); if you
use a standard temperature converter to convert rates, you will not
get the correct answer.
Instead, you need to do the calculation
using a "Rate Converter." This is the second calculator at the
top of this page. A rate of 200 degrees F, for example, would
convert to around a rate of 111 degrees C. Similarly, a
rate of 200 degrees C converts to a rate of 360 degrees F.
Note that these are different answers than the ones given by a
Temperature Converter (discussed in the second paragraph above).
Confusing a temperature conversion with a
rate conversion is common, but it's a pitfall to be avoided.
The differences can cause a firing schedule that worked fine in one
scale to be incorrectly converted so that it yields poor results in
the other scale.

Copyright 2006 Brad Walker.
All rights reserved.
The formula for converting F to C is C = (F  32) /
1.8
The formula for converting C to F is F = C x 1.8 + 32
The formula for converting an F rate to a C rate is C
 F / 1.8
The formula for converting a C rate to an F rate is F
= C x 1.8
