Originally Posted by John long
Brian is giving you good advice here but one thing concerns me. You indicated you were using a DA for the initial blocking. If this is a fairly flat panel a DA is not adequate. Use a long firm sanding block or air file and sand in a sideways crosshatch pattern as you see in the videos. Best of luck.
I don't use the DA for blocking, just for knocking down the big stuff like the ridges left behind from the spreader and to remove obvious areas where the filler is piled higher. Once that stuff is taken off, then I guide coat and use my Durablocks. I do always block in a cross hatch pattern. Thanks.