Tuesday, April 28, 2015

computer lab day:1

Pit firing is the original method for “baking” clay.  It dates back nearly 30,000 years ago.  This process is done typically in a hole in the ground, or a pit, pots are placed in the pit and burned.  Pit firing is an atmospheric process all of the colors and patterns are derived from the process and what is consume in the fire.  Items that are burned will turn to vapor and will swirl around the pieces in the pit.  If the pieces are hot enough to have their pores open the colored vapor will enter the pore and stay there, if not pot will not have color besides black, gray, or white. There are several variations in which to do a pit fire, this will become up in smoke.

Saggar firing was originally developed to protect wares from ash-slagging and flame-flashing in wood firings, but in contemporary use, with clean-burning gas firings, the process is used in exactly the opposite way
Saggar Firing is the method of creating confined atmospheres within a container or saggar.  The saggar can be made out of anything depending on the type of firing from the traditional refractory clay to newspaper.  Originally saggars were used to protect the finish from the debris flying around the firing chamber from the wood or coal fuel source. Roughly 200 years ago, potters decided to reverse this and use the saggars to hold material near the pieces to dramatically change the finish.