I thought my marmalade hadn't worked. It took ages before it would set. I think I added too much water for the amount of oranges. Eventually at around midnight, after the rest of the house (Niels) had gone to bed, a tiny little hint of a wrinkle appeared on the saucer when I tested for a set. Hurrah, we shall have marmalade for another year. It tastes delicious, even if I do say so myself! And, for those marmalade makers among you, the oranges I used were left over from last year. I put them into the freezer whole and they did their marmalade thing perfectly - if a little slowly, and I think that was because my measuring wasn't quite right.