I am in the process of building my first boat. I have recently completed clinching the hull and was in the process of faring in preparation for canvas. My question is about tack depth because it seems that I have driven some/most of the tacks too deep. After I soaked the hull, the hammer blossoms all came out but about 60% of the tacks now have a depression around the tack head between 0.5 and .0.75" in diameter and roughly 1/16" deep. It is too late to do anything about that now, but my question is about filling these gaps - should I fill them all in and then fair and sand the hull, or will that size hole be spanned by the canvas and not require any further action? If the answer is fill them in, any suggestions as to what type of wood filler to use?