Any 2 nuts with the flat sides together will amount to a 120 degree included angle which is acceptable for general purpose use. When pointing drills freehand pay close attention to the symmetry of the cutting edges as if one is longer than the other it will cut twice the difference oversize. Clean a drill doctor after each use to keep its accuracy.
Same here. An old time machinist taught me how to hand sharpen drill bits. It's a bit of a practiced art. Today I use Drill Doctor gets the right pitch and tip angle. Then after that I just dress the drill between sharpening.
This is no doubt the place where all drill grinding experts hang. I supervise a bunch of red seal journeyman machinists less than half of which can repoint a drill freehand that cuts less than. 005" oversize. Drill nomenclature is very involved to truly master accurate regrinding and when hole size is important its not as easy as it looks.
The experimental aircraft guys, that have to drill thousands of rivet holes in their projects, seem to like the Drill Doctor.
I have a Drill Dr and love it for bits under a half inch. It really does a good job. For bigger ones I went on line and watched some YouTube videos on how to sharpen them on a grinding wheel and found out I was doing it all wrong, no wonder mine never were sharp. After I learned how to do them I was able to sharpen bits up to an inch and bigger with great results. My suggestion is to go on YouTube and put in "How to sharpen drill bits". There are some hokey videos, but also some very good ones by guys who explain it and show it well. Don
there are different versions of the drill dr. a commercial grade which works great and a home depot version which wont even sharpen a pencil
Actually southeast.... I've driven by the turn off on I-10 many times.... I think there's a hot rod restaurant there now ... always wondered who the town was named for.... Photo of Samuel Morse's first telegraph key made by Alfred Vail.... http://www.150.si.edu/150trav/remember/r818.htm
OK now this .005 oversize changed everything. I was taught how to sharpen drills 30 years ago by a 70 year old dutch machinist. Its not hard to do if you pay attention to someone whos showing you and have them watch a couple that you do with some feedback. At least for me it wasn't to get them repointed. I have more trouble with the smaller (less than 5/32) ones than the bigger ones. He showed me how to do augers, paddles and forstner bits too. Holding that .005 by eye free hand on a grinder is more than likely a God given talent and not something you can learn. Kind of like these no filler needed panel beaters.
Well my goodness...I'm lovin' this place. Thanks for all the wonderful input. I'll check out those videos. In the mean time it looks like a few will have to go to the shop for some serious rehab, while I practice not messing them up too bad. Ended up buying a couple fresh ones to finish up the task at hand. Thanks again!
One tip I can pass along for hand sharpening is to hold the drill up to the light and use your other hand to form a circle that you look through to eyeball the tip of the drill. Focussing only on the silhouette of the tip makes it easier to judge if the grinding is equal on each side. Mart.
Drill Doctors are made by Darex Corp. which is the brand name for thier industrial models. With heavy use the collets wear out from grinding grit so avoid well used ones. The other is a Pine universal, the best there is IMO and the style to look out for.
I noticed on my Drill Dr that the marks on the dial were off a few marks so when I sharpened them (before I discovered this) the drill points were lower than the trailing shoulder of the tip and the damn things couldn't get enough bite drill pine boards.
I just use my Darex M5, up to about 1-1/2" bits. It will also split the point and thin the web. Works great.
Get a 'drill point gage' for free handing on a grinder. They come in different $ values - they are available on EEEEEEEEEEEbay.
Hi ... I have done mine freehand on a bench grinder for 58 years....there is some skill involved in the angle and rolling the drill.. but once you get it.... you would never use a tool stand again....my uncle was a toolmaker and taught me when I was about 14 how to do it....... any thing over an inch I take them to a tool maker to sharpen.....
Well, due to this post, I spent the afternoon in the basement sharpening all my drill bits that needed it..........thanks for motivating me !
i always do it on the bench grinder. on a side note, i work in a workshop full of mechanics, some who have been in the game for a lot longer than me and i'm the only one aside from the boss who knows how to do it. the only reason i know how to do it is because the grumpy old bastard i did my apprenticeship with gave me a great big box of blunt drill bits one day and told me not to come back until they were all prefect, i was there for almost a whole day
Haha, when I bought my Drill Dr I did the same thing. I had a huge box of dull bits and I sat on a stool and over the span of a few nights I had them all nice and sharp and sorted by size. It was kinda theraputic. It's so nice to reach for a bit now and have it actually sharp enough to drill through something. Don
the bit should not come toa point it should have a flattened S curve... I ran a very expensive drill point re storing machine years ago as an aspiring machinist.. look at a new bit and see what I mean
I AM the grumpy old bastard but it takes my guys years not days to get it right. Anybody who mastered this in a day fucked up not becoming a machinist.
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