BUILDING A HEAT TREAT FURNACE

Building a small heat-treat furnace for the shop. This furnace is made from standard fire brick, 2 1/2 x 4
1/2 x 8 inches. Fire brick does vary in size, so the size shown in the drawing may have to be changed to
fit y our needs. Another style of furnace is where the main opening is at the top, and the part hangs down
on the inside. This seems to give a uniform heating.

A-Gas/Air outlet; B-Furnace opening; C-Side view; D-Opening for temperature sensor; E-Blower;
F-Gas intake; G-Heat sensor pipe; H-Heat sensor opening;

You will need eight firebricks to make this. When completed you will have a furnace with an inside size
of 4 1/2 x 3 x 8 inches. This size will handle just about any job in the shop.

The firebrick is mortared together with the cement used in fireplaces, and it should not be any problem
to get from any business that sells fireplaces or wood burning stoves. The brick is placed 2, flat side by
side, mortared, and then one brick on each side is stood on edge, (see drawing) mortared to the two
laying flat.