Thanks McCreed
I think you might be right. The sponge did make a real difference but I just put 2 more coats of Mahogany on it and I can still see discolouration. Looks like a full strip back is needed.
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I do find that applying new stain, even on old set stain, can dilute the previous colour. The 'Colour Enhancer' does the same. It's good as lang as I don't over do it.
Bradboy