I use sawblades exclusively for making blades and choppers of all kinds. I have never used an edger blade, but as long as it is thick enough and high carbon steel.....go for it. Now, I use sawmill round blades which are L-6 and this steel is similar to 15N20. The great old heavy bandsaw sawmill blades were composed of 15N20 and made in Uddeholm Sweden and is a superb steel. The late David Boye made many of his blades from both the L-6 and the 15N20. Unfortunately, the 15N20 bandsaw metal is all but extinct and much of it was gathered up during the metal drives during WWII. New 15N20 is made, but is thin and used to make damascus. There may be someone out there in knife-land that knows the whereabouts of thicker...1/8, 3/32, etc. 15N20. Don't forge the good steel in concrete cutting blades both large and small. I don't know the composition of this steel but I have seen knives made of it and they appear to be solid. Also crosscut saw blades of many descriptions. You will find that having blades cut via a plasma cutter will save steel and save you mucho time at the grinder cleaning up the usual torch cutting. If memory serves the 5160 steels are those found in flat and coil auto and truck springs.....also great steel which will take a great deal of shock. This is spring steel. Many on the Neo-Tribal thread use 5160 as well as the other high carbon steels such as 1095, 1080,etc. The last two numbers indicate the carbon content in points. At one time or another I have made knives from coil and flat springs (especially the smaller overhead door springs), planer blades, railroad spikes, re-purposed kitchen knives, pre-made blanks, and various engine parts. Forging will allow you to use many different shapes and bend them to your vision. These days I prefer not to pound a round spring into something flat, but I still do it on occasion for smaller blades. The flat steel from sawblades is more efficient, but has its creative limitations. Its all about what YOU want to do and your vision of the blade you wish to fabricate. All that being said, it is really not necessary to purchase expensive steel to make blades.....there is plenty at the metal scrap yard to keep you busy for a lifetime. AFter all, many have used elevator cable to make very fine blades.