There is several tricks when using drill bits on sheet metal one always us a good lubricant that won't fly off your metal. They make some special lubs for S/S which keeps the bits cool but when the bit starts to get dull or you do not keep the right pressure against the S/S you will work harden it. When you get older your eyes are not as sharp as they used to be. For bits HSS when sharping them they have can't remember the taper 59 degrees comes to mind but take two standard american nuts and put them together and that is the correct taper to sharpen them at. You can refer to this angle from 1/16" to 3" drill bits. When you free sharpen on a grinder you can see if you ground the taper and relief correctly.
While we are on the subject of cutting holes a lot of you use Hole Saws. A neet way to keep the saw blade teeth cool is use Crisco Lard like your wife or mom used to use it works great and the Hole Saw Last a lot longer.
62Blue
Don
Last edited by Don G.; 03/18/2010 8:49 AM.
