I just mixed and put on Blanchard's filler recipe as found in the knowledge section. It is: 5 lb silica, 1 qt spar varnish, 2 qt boiled linseed oil, 1/2 pt Japan dryer. I used 5 lb of #320 silica I got from a pottery supply in Nashville. "Flour" they call it and it seems about as fine as flour. Used 1 qt polyurethane since that is what I had on hand. Boiled linseed oil and Japan dryer from Lowe's. It is a very thin filler, more so that what I bought from a NH supplier last year. I brushed it on. First coat took the most. Second coat exhausted the mix. It is 15 ft canoe. Examination from the underside seems to indicate the weave was penetrated clear through. It is #10 canvas. Being thin the filler really soaked in. Now for the hard part. I can tell that finishing a filler coat is like finishing concrete, something I am not real good at. Even so, I am hand smoothing it trying to get a smooth sheen. Mixed success. Obviously, timing, like with concrete, is everything and I only vaguely know what I am looking for. Like with concrete, this will take a lot of practice. Pictures from just after the second coat was brushed on.