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Bottom Knocker


A Twitter acquaintance, @sherylcoleman*,  responded to a question of mine and used an infrequently used title, Bottom Knocker, as part of her response.  Take heart.  A bottom knocker is nothing kinky, not related to corporal punishment, nor is it a reference to sagging anatomical parts… it is a term used in earlier centuries for an apprentice who worked in the ceramics shop who was responsible for pounding out the clay bases used in the making of saggars.  OK. That is a lot to absorb for my non-ceramic friends.  A saggar is a lidded container used within a glaze firing kiln to hold bisque fired pieces for out-of-the-ordinary glaze firings.  By placing a bisque piece into a saggar, the artist is able to achieve unusual and often unpredictable results in surface coloration due to the controlled atmosphere and chemicals/minerals within the saggar container.

I am constructing several saggars at the moment for experiments with ceramic musical instruments….probably ocarinas, rattles, and small drums.  The clay mix for a saggar is generally about 50% fire clay and 50% grog.   The grog is necessary to handle the extremes in thermal shock from high temperature firings when the saggar is re-used in multiple firings.  Several have advised me not to attempt wheel-throwing  saggar clay because the coarseness from the grog makes it feel like you are throwing sandpaper.  I may give it a try on a small piece.  We’ll see if I have any fingerprints left afterward.   If only that coarseness could be used to grind off the season additions of my bottom…I wouldn’t knock that 🙂

*Sheryl is also the author of a fiber arts and flute blog with a very cool name, Crunchy Banana.