One thing to watch out for: sometimes when you cut a full sheet of lapping film down to size there is a bit of a lip along the cutting line. I think the happens more if your knife is dull.
Once your film is stuck to the acrylic block, tape a small piece of sandpaper (I use 220 grit because that’s what I have close by) and sand that lip off. Just run it up and down the length a few times. You’ll sand the edge of your block a bit at the same time which is good, sometimes they have a lip from cutting as well.
Once your film is stuck to the acrylic block, tape a small piece of sandpaper (I use 220 grit because that’s what I have close by) and sand that lip off. Just run it up and down the length a few times. You’ll sand the edge of your block a bit at the same time which is good, sometimes they have a lip from cutting as well.