For the past couple of years I have been using some Burr Oak from a huge tree where my wife grew up. I had the tree milled and kiln dried. It isn't the greatest material due to knots and other imperfections but on the right project I like the "rustic" look of the wood. Over time the pile has become pretty well picked over and I am left with the pieces with a lit of larger knots, voids and other imperfections. In the past I have used a mixture of wood glue and sanding dust to fill minor imperfections, mixing up a batch about the consistancy of peanut butter. So, on to my question...

This time, because of some larger imperfections I would like to use West System epoxy to make my "wood putty" due to the larger voids, knots, etc. To what consistancy should I mix sanding dust into the West System epoxy so that I still get a good color match but not lose the ability for the epoxy to "flow" into the voids? Any other thoughts? Thanks.

Hope that all made sense!