Drill Doctor

Went back a reread the manual.
It says to move the setting for the alignment setting from split point, counter clock wise, to standard point.
I'll try it and see what happens.
 
I had a drill doctor and a Oliver of Adrian drill grinder, used the doctor for small drills and the Oliver for drills up to 3"; it was worn, but it would still do better than by hand; nowadays, I mostly grind them by hand, but can still go to my old shop and use the machines; my doctor did the split point and worked well, although I did have to adjust the setting fixture to get enough clearance for free cutting.
 
I have the 750 and it made sharp bits that wouldn't cut. I found I had to increase the relief angle on the settings to get them to cut.
I have had one for several years. I find this myself. The bit is sharp, but does not cut well for the first two or three attempts. I assume, that until I get the relief angle a bit "relieved", it rubs a bit. After that, it cuts better than I can do myself, at least for the smaller stuff. I like the thing, I use it regularly, but I recognize I can make a "sharper" bit. NOT a more even, or long lasting, bit. Just a "sharper" one.
 
I have had one for several years. I find this myself. The bit is sharp, but does not cut well for the first two or three attempts. I assume, that until I get the relief angle a bit "relieved", it rubs a bit. After that, it cuts better than I can do myself, at least for the smaller stuff. I like the thing, I use it regularly, but I recognize I can make a "sharper" bit. NOT a more even, or long lasting, bit. Just a "sharper" one.
Look at the drill at intervals while grinding it. Leaving it in the holder, pull it out and look at the drill carefully, under good light, with corrective lenses if necessary. The chisel point should typically be at about 45-50 degrees to the cutting edges, depending on what you are going to use it for. Larger angle, gives less back relief, better for harder materials and shallower feed rate. Smaller angle, more back relief, better for softer materials and deeper feed rate. Also look at the side of the drill, at the angle of the back relief is visible where cutting edges meets the side of the drill. Less angle gives slower cut, more angle gives a more aggressive cut, but less strength. Look at the sharpening tool manual and at the link in post #7. Get a drill point gage so you can check for equal length cutting edges and equal and desired angles of cutting edges to shank.
 
I have had one for several years. I find this myself. The bit is sharp, but does not cut well for the first two or three attempts. I assume, that until I get the relief angle a bit "relieved", it rubs a bit. After that, it cuts better than I can do myself, at least for the smaller stuff. I like the thing, I use it regularly, but I recognize I can make a "sharper" bit. NOT a more even, or long lasting, bit. Just a "sharper" one.
Look at the drill at intervals while grinding it. Leaving it in the holder, pull it out and look at the drill carefully, under good light, with corrective lenses if necessary. The chisel point should typically be at about 45-50 degrees to the cutting edges, depending on what you are going to use it for. Larger angle, gives less back relief, better for harder materials and shallower feed rate. Smaller angle, more back relief, better for softer materials and deeper feed rate. Also look at the side of the drill, at the angle of the back relief is visible where cutting edges meets the side of the drill. Less angle gives slower cut, more angle gives a more aggressive cut, but less strength. Look at the sharpening tool manual and at the link in post #7. Get a drill point gage so you can check for equal length cutting edges and equal and desired angles of cutting edges to shank.

I use a SRD drill grinder that I purchased used off eBay. It too is tricky on the relief when sharpening drills. I attached a link to my video showing me using my drill sharpener


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I use a SRD drill grinder that I purchased used off eBay. It too is tricky on the relief when sharpening drills.
Drills have varying helix angles, which affects where the tooth rest locates in relation to the cutting edges. That is an issue when grinding drills on any type of fixture.
 
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