DRILL DOCTOR ANGLES

[kenmac]

When in a hurry I sharpen by hand . I tend to add too much relief.

 

[Scooby074]

For hand sharpening a drill gauge like this can help keep your cutting edge angles correct and centered. One of my first projects in school was making one. I dont miss the filing and polishing one bit.

 

[scott_vt]

Here is some good reading.

http://www.newmantools.com/machines/drillpoint.html

Good Evenin J_J,
Thankyou that was a very good read !


As an example, craftsmen assume that the 118ｰ point is a good compromise or general purpose point for drilling a variety of different metals and this erroneous information appears in machine shop textbooks. Varying the point angle has nothing to do with cutting action. The 118ｰ point is pure myth. In reality, a compromise between high and low lip clearance angles is the determining factor for a general purpose cutting tool, NOT the (non-cutting) point angles !

Like I said earlier, someone that has a drilled a few dozen holes in their entire lifetime, and states that a certain included angle is gospel, is pure BS IMHO !

Thankyou,

 

[escavader]

Yes THANKS for that article JJ.I learned a few things.
1]The split point on my drill doctor is going to be useless on my bits above 1/2.
2]The 119 degree angle doesnt mean beans ,its the clearance angle thats important.
3]Id better stick to sharpening 8 knife multi pattern planer knifes ,and leave the big drills to an expert.It would be easier to buy SCOTTY a case of beer,drive to VERMONT and get him to do them,while i admire that lil FARMALL
now seriously i did pick up alot of info from that thankYou.
ALAN