09-02-2013, 10:21 AM
Tom
Thanks for sharing your knowledge with the group! I've been grinding about an hour a day on drill bits. Now I got a question, I have some bits that are old been ground upon years ago and damn near 60* point they are less than 90???? a couple are #2 jt all are about 1/2" I've spent a bit of time just getting the close to 120* As not to over heat the bits, coolant and swapping them around has prevented that. I just dawned on me maybe these were ground to drill..... gold? platinum? beer cans? I didn't just regrind special bit back to normal? These bits are from boxes from yard sales, auctions, swap meets (can't throw good steel away!)
One thing I did to help in this regrinds is I marked the tool rest on the grinder at 60* from perpendicular to the stone, sure gives e a better target, I tend to be thinking of other projects when doing something repetitive or in other words I don't pay all that much attention to what the heck I'm doing.
Thanks for sharing your knowledge with the group! I've been grinding about an hour a day on drill bits. Now I got a question, I have some bits that are old been ground upon years ago and damn near 60* point they are less than 90???? a couple are #2 jt all are about 1/2" I've spent a bit of time just getting the close to 120* As not to over heat the bits, coolant and swapping them around has prevented that. I just dawned on me maybe these were ground to drill..... gold? platinum? beer cans? I didn't just regrind special bit back to normal? These bits are from boxes from yard sales, auctions, swap meets (can't throw good steel away!)
One thing I did to help in this regrinds is I marked the tool rest on the grinder at 60* from perpendicular to the stone, sure gives e a better target, I tend to be thinking of other projects when doing something repetitive or in other words I don't pay all that much attention to what the heck I'm doing.
oldgoaly, proud to be a member of MetalworkingFun Forum since Jun 2013.