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7CommentsJoined January 20th, 2015
Eldon RV 147 CR2240 Greenville, TX 75402 903-455-0780
  • How to Sharpen Used and Dull Drill Bits (By Hand!!)

    Yes, you get a correct cut IF you have the right feed pressure and right RPM for the bit, type, size, and material being cut. You can ruin a good drill bit by overspeeding and / or not bothering to lubricate. OTOH, I've seen lots of people turn a drill bit into a screw (or pencil point) trying to 'rotate' it when they sharpen it, by hand or 'drill sharpening' machine.All you really need to do (lets assert you can get 135 angle , etc correct)... is get the lip even and established, provide support for it so it doesn't chip, and if you will slow down a little... you'll relieve that 'rear edge'. It doesn't have to be a lot... practice and comparing it to new bits will help you get both sides even and to the correct amount. For what it's worth, I was taught this (and a lot of other l...

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    Yes, you get a correct cut IF you have the right feed pressure and right RPM for the bit, type, size, and material being cut. You can ruin a good drill bit by overspeeding and / or not bothering to lubricate. OTOH, I've seen lots of people turn a drill bit into a screw (or pencil point) trying to 'rotate' it when they sharpen it, by hand or 'drill sharpening' machine.All you really need to do (lets assert you can get 135 angle , etc correct)... is get the lip even and established, provide support for it so it doesn't chip, and if you will slow down a little... you'll relieve that 'rear edge'. It doesn't have to be a lot... practice and comparing it to new bits will help you get both sides even and to the correct amount. For what it's worth, I was taught this (and a lot of other little machine shop tips) by the First Machinist Mate, USS Floyds Bay, a seaplane tender. On those things, they pride themselves on the ability to make anything, anytime to exact spec, to say the least. Problem is... this was during the Korean War, when you didn't have programmmable CNC machines, and etc. Nearly everything was done by hand to some extent, and came out right EVERY time. I grew up performing to the same USN spec. Errors were not tolerated, you were expected to know what you are doing and why. I'd rather see somebody grind a few bits down to nubbins learning to make them right .. than see them plop them into some machine and "hope" for the best ggg

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  • How to Sharpen Used and Dull Drill Bits (By Hand!!)

    In the 'olden days'.. we always had a grinding wheel and wire brush mounted on a arbor with (gad) no shield. The motor is on the bottom of the pedastal, with av belt up to drive the arbor. Is is NOT a positive drive machine.. if you get stupid about how you use it you can stall the grinder without stalling the motor, and not get hurt. The trick to sharpening bit is as this fella described, except one thing:With more room to move, you do NOT twist the drill at all.Get the angle right, then -starting at the lip, you move the drill bit straight up, vertically. Follow the natural curve of the grinding wheel. If you look at a clock face.. you would follow the face of the wheel from about the 5 (or 25) mark on the clock, straight up to about the 2 (or 10 min mark). Small drills are more...

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    In the 'olden days'.. we always had a grinding wheel and wire brush mounted on a arbor with (gad) no shield. The motor is on the bottom of the pedastal, with av belt up to drive the arbor. Is is NOT a positive drive machine.. if you get stupid about how you use it you can stall the grinder without stalling the motor, and not get hurt. The trick to sharpening bit is as this fella described, except one thing:With more room to move, you do NOT twist the drill at all.Get the angle right, then -starting at the lip, you move the drill bit straight up, vertically. Follow the natural curve of the grinding wheel. If you look at a clock face.. you would follow the face of the wheel from about the 5 (or 25) mark on the clock, straight up to about the 2 (or 10 min mark). Small drills are more difficult, and too many people make a big deal about 'relieving' drills that really don't need it. That 'back cutting' action is really easy to damage the nice new lip you just created..

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