[I haven't used this particular brand, but most oilclays (and other greasy gunk too) can be removed by using salad oil as a pre-wash. The vegetable oil dissolves the grease, most of which can then be rubbed off with paper towels. The residue will come off with soap and warm water- save your credit card for better things...
As for increasing the firmness of your clay, I suppose you could try wedging in more clay powder, but probably the best (and least carcinogenic) thing would be to save this for winter use and get some firmer clay for summer. Or you could mix your own, using more wax and clay, less oil and grease to increase the firmness.]
Andrew Werby
UNITED ARTWORKS- Sculpture, Jewelry, and other art stuff
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