Whilst working on a flat surface, turn the adjusters to loosen the retaining bar and load the blade into the holder. The 45 degree angle should be facing the back. Pinch the bar and blade against the body of the holder, making sure the cutting edge stays flush with the sole, and tighten the retention setscrews to set the position. Use a scrap piece of wood to check the shavings are of equal thickness on both sides. By adjusting the central thumbscrew in the main body of the scraper, the blade is forced into a slight curve which then causes the blade to flex through the mouth of the sole. Further adjusting a tiny bit at a time enables you to set the depth of cut until shavings appear.
When sharpening the #80 scraper, the angle should be as close to 45° as you can get. With the blade in the vise, use the flat file at a 45° angle using a continuous stroke from one end to another, this creates a smooth, straight edge. To achieve a 45° angle, you can measure and cut a piece of wood as a guide. To see how to make this, see Paul’s video here.
To remove any unwanted burr, place the flat side (non-bevelled) against the super fine plate on the diamond plate and rub back and forth.
Next, flip the scraper so the bevelled side is facing down on a flat solid surface. Then run the burnisher along the face 30 times keeping it flat.
While holding the scraper on end against the workbench pressing down with your hand, use the burnisher against the bevelled edge and pull up 10-20 times, keeping the angle as close to 45° as you can. Make sure you have something to protect your palm from the scraper blade when doing this. For the final few strokes, increase the angle by a few degrees, this will give the scraper the turned edge. Repeat these steps on the other cutting edge if it has a 45° bevel.