Tammi, I Used shellac flakes for many years in furniture restoration and yes if it is fresh will cure faster. I have been using the pre-mixed shellac on the old sewing machines and their cabinets with no problems. I just make sure the can is fresh when I pick it up from one of the big box stores. I do let it cure for a few days to make sure it gets hard. The key with fresh shellac canned or flakes is to apply thinly let cure a day and repeat. Three coats is all that is needed on wood. Let cure a week or two before waxing to protect the finish. The pre-mixed shellac shelf life is only about a year. I usually use up a qt can in about three months so never had to worry. Shellac does not like humidity. The lower the better for curing if to high the shellac will develope a white haze and will not cure properly.
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