end blades are generally a bit thicker and are made to use on scroll saws that require pin end blades which are generally older, less expensive or made for entry level scrollers. Most newer higher-end scroll saws do not accept pin end blades. Blades come in many weights, ranging from #10/0 (for making jewelry—about the size of a coarse hair) to #12, which is similar to a small band saw blade. Another variation is called a reverse tooth blade. On reverse tooth blades, the bottom of the teeth are reversed (point up). This arrangement helps to reduce splintering on the bottom edges of the cut. However, it does not clear sawdust out of the cut as well as a regular blade, so cutting is slower and produces more heat. This heat reduces blade life and makes scorching of the workpiece more likely. Reverse tooth blades are especially useful when cutting softwood and plywood such as Baltic birch. The latest variation is called "ultra-reverse". These blades are configured with 4–5 teeth down and then one up, repeated through the length of the blade. The blade clears dust very well and leaves a much cleaner back (very few "fuzzies"). These blades' sizes range from #1 through #9. References Further reading Saws Woodworking machines