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twisted bottom bubbles

updated tue 23 sep 03

 

Kathie Wheater on mon 22 sep 03


Randy asked:
>>I seem to be getting twisted type air pockets in the bottom of pots that are
>over two pounds. Small mugs there does not seem to be a problem. Usually
>the pockets are smaller than a quarter.

This happens when you throw the clay on the wheel head and air
gets entrapped between wheel and clay.
Make sure the clay is smooth and tapered when you plop it down.
If it's a round ball, even a slight indentation from holding the clay can
capture enough air to be significant when you compress it and work
it up when centering.
If you do have a bubble on the bottom, slice a line concentrically and recompress
from the outside wall inward. Sometimes this will simply force the air up toward
center and you can tweek it out. Mke sure you work it back out again.
All this compression also helps to prevent the evil...
~ ~ ~ ~ ~ ~ ~ ~ S - CRACKS ~ ~ ~ ~ ~ ~ ~

Good Luck,
KathieW
Patiently waiting to move to Alabama????!!!!!!