I think this was the clearest explanation I've ever got on drill geometry. You still have the touch, Professor!

Served my AP at Ed Johnsons shop from around 69 to 75 , one of my jobs, at end of week, was to sharpen all bits in shop , not a big shop, but with up to 4 men working daily, those bits would pile up ! I used the same sharpener you have rebuilt, being the only AP In shop, I also did the other clean up sharping on lath bits to spec. Good info you show here and lots of memory's kicked in Thank you for your work !

Outstanding & thorough video (as usual!)... never hurts to review the basics. Thanks!

The best drill geometry video ever...in simple languange that anyone could understand, thank you so much...

Mr. Pete, I agree with Rein Rapp from 'The Engineers Black Book' who said this video, dealing with twist drills is the best on KZfaq. You, sir, have created yet another benchmark. Go to the top of the class and have a nice coffee. Most sincerely. Joe from Bonnie Scotland.

great to see all this detail and covering a lot of the theory behind grinding drills. I still remember when I was about 13 I got a 30 second lesson from my dad (who was a heavy equipment mechanic and didn't do much drill grinding) It consisted of making the web straight, and not much more. I have learned the rest through trial and error and now I have pretty good dumb luck results on sharping of drill bits. I hope this real knowledge doesn't cloud my dumb luck.

Lyle - excellent video once again - you had me riveted in watching this with your concise explanation on the mistakes and errors that can be made on grinding these drill bits. Thanks for explaining this so well. John 🇬🇧

Mr. Pete, That was an awesome example of teaching. Clear, concise and full of all the necessary details.Thank you so much for producing it. This video should be a definite keeper for everyone. Thank you for sharing! Joe

Most excellent! This will be referred to and immediately become a top drill sharpening reference. Jim

Thank you Mr. Pete! A video about all of the teaching aides that your company sold would be great.

Unbelievable how a simple drill bit is so complicated and misunderstood, I have certainly learned more priceless knowledge from a true master.

I really enjoy your informational videos. Thanks Mr. Pete!

Good information is never wasted . Thanks Lyle. I have a box of bits that belonged to my Dad . He always handground them I'll have to look at them. I use a Drilldoctor.

Superb info Mr. Pete, thanks for sharing! And another Tubalcain Cutaway! Of a drill bit no less!

Great video Mr. Pete. Very succinct and very understandable. Thank you.

1000x times clear explanation than our teacher. Thanks a lot.

Great use of metric Mr Peterson! In Oz shops we are mostly metric, but imperial literate. Your use of metric in place of decimal imperial was spot on! There’s hope for a world where inches and millimetres can live in harmony...

A little late to the lecture this morning Professor, very informative in scope......great photography and descriptions.....Thank You Lyle......best wishes from Sunny Hot Damp Florida, Paul

Indeed excellent and most educational. The part I loved the most is when you “in fact some old-timers ...” because says a lot about yourself, always young. Thank you very much.

At last I find on the net good and clear explanations about drill bits geometry ! Thank You mrpete222.

Excellent tutorial on drill bit theory! I lived decades working in machine shops from Cleveland Ohio and appreciate your vast knowledge on this subject. So much of the basic theory have been lost in this highly technical CNC and advance world of manufacturing. I also went to E-Bay and amazon to order the help materials you recommended.. I would highly recommend this video for engineers, machinist, CNC programmers, trade school teachers, hobbyist and all that wish to have a technically through understanding of twist drills. Mr. Pete, thanks for taking the time to share your knowledge on this subject.

This has got to be the best drill geometry video on KZfaq. Thanks Mr. Pete!

Lyle -- Good stuff! Thanks. I will watch again.

"The Use and Care of Twist Drills". The label says "Sold by Vonnegut Hardware". This business was started by writer Kurt Vonnegut's grandparents in Indianapolis.

Excellent information. I appreciate your detailed explanation.

Thanks Mr Pete I saved this one to my favorites.

As always, great video. I was a shop teacher for many years and I can recognize and appreciate how well organized your presentations are. You are a good teacher.

Very good video. On varying my angles some has to do with material hardness but also thickness. On sheet metal I increase the cutter angle but I reduce the relief angle. Maybe that is wrong but it seems to work for me. On real thin metal I try to use a punch if I can get at it. On thick material over 2 inches I use a boring bar mainly because I can't afford anything over a 2 inch drill. Thank you again for sharing your great knowledge. Many times in the shop I give you thanks.

I think you should make a separate video about web thinning. It is very useful to know how to do it. Both as you said for shortened drill bits, and for drills with heavier webs. Like 135 deg cobolt drills.

Excellent video Mrpete 👍Very well put together and thought out. I want one of those teaching aids. Would look great in the shop. I may need to make one.

I learned a great deal from the Use and Care Of Drill Bits series. This was a good refresher. I look forward to the next in this series. I enjoy your videos very much, the information and care you present, but also your almost soothing voice. Why yes, I am crazy. Why do you ask? It's a good crazy. Thanks.

Good instruction, as always. Thanks, Mr. Pete! :-)

You are able to teach very well. I found so.e useful tips I don't know. I was very impressed with the rebuild of the Lisle grinder for someone who said he doesn't like to paint. I am looking forward to your next drill sharpening video. Thanks

Great video. I make industrial wheels and have drilled thousands of holes in thick plate steel. You’re instruction is spot on.

Great teacher! Thank you Mr. Pete! :)

Thanks for the quality content as usual!

The most educational thorough instruction thank you for sharing your knowledge

Very informative. Thanks Again! You are the man.

Now that's the teacher I looking for Thanks Pete

Very informative and things I don’t know about drill margins will not cut. Thanks for sharing

Got into the tool and cutter dept at Worthington Compressors in the early 70's.The old timers liked me and would teach me how to sharpen drills, end mills ,and braised in carbide cutters.The job lasted a year and then got to be a millrite and worked with a bunch of really talented men for another eight years.That was my formal start to a thirty year career of repairing some of the best built tool room machinery from around the world.

Very useful information, Professor. Thank you for sharing your tremendous insights!

That hand ground bit was PITIFUL! :) We always free hand sharpened and that would have got you put on clean up. I'm hoping that putting a rake on the bit is discussed at some point. I remember that it was used for softer metals such as Brass, but I'm a little foggy on it. I think it had to do with the chip formation. Great video as always and thanks Mr. Pete.

Great job explaining drill bits Mr. Pete!

One of the best training's on the basics of bit geometry I've seen Mr. Pete! Never knew that about the web changing size, but makes perfect sense now why I've had trouble resharpening one that broke ~1/4 of the length down. Also the Chicago chart with the preferred angles make sense at some level but would think it really depends on the material it's cutting (steeper for soft, shallow for harder?) Thanks, Learn Lots and got the synapse firing again!

This is a really great video.

Great instruction. I took shop & have used several pieces of tools/equipment. But, I learn something every video.. My "pet peeve" is that so many people I know will not take simple suggestions for drilling (especially metal) and they just abuse their equipment. Shop tip: Keep old bits for idiots to borrow..

Awesome video

i alawys enjoy your videos mr pete

Thankyou Mr Pete.

Thank you very much for explaining that the "Margin" is part of the "Land" - The Land being the entire distance between the Flutes and the Margin being that part of the Land that actually touches the work. As far as Web Thinning goes, everyone now wants to "Split the Point" to stop 'Drill Wandering'. Everyone seems to have forgotten about drilling pilot holes. There's even 'Four Facet' sharpening which seems to sidestep a lot of drill geometry issues.

Thank you for a very good video.

Nice video Mr Pete alot of information here. Thanks

Excellent lesson Mr.Peterson! I suppose teachers never actually retire, they just stop working at a school everyday.However they never stop Teaching. And I am glad to attend your classes!

Dang. I wanted to give two thumbs up. Thanks for another excellent video Mr. Pete.

Outstanding video, thank-you "Teacher". As always thank you for taking your time to make this video. And I support this site. ~M~ NJ 07922

Thanks for this video! I've always known that drills were complex in their geometry. Looking forward to the drill grinder videos! I can tell you that I understand how the Baldor single phase motor works on your Lisle drill grinder... but anything beyond that is over my head! :)

Excellent video sir

thanks Prof Peterson

Thank You for another very informative video. I have been waiting for someone to show how to sharpen small drill bits and I have saved a few to do just that. I am very pleased to hear that you don't sharpen small drill bits as I was not very confident about doing it. I am not even that confident about doing the bigger drill bits, but I have plenty of old ones that i can practise on.

Thank you sir, for the excellent video and passing on your knowledge. I am learning drill sharpening as a hobby, and sharpened 30 drills in the last 2 days. love the learning and turning dull drills in to some thing usable. I consistently get a big rrelief angle or heel, have ordered a protractor to accurately measure. I noticed the Web thickness on a cobalt or titanium drill can not be sharpened without grinding the Web thickness. will have to rewatch this video and your others on drill sharpening.

Great video!

Best I've seen on this subject.

awesome information. great vid mr p

Good explanation. Thanks. Question: I've noticed a problem with newer drills that did not seem to happen with drills made years ago. When drilling through something and when the tip exits the material, it seems to grab and quickly/violently pull the drill completely through. Thus, damage can occur when the drill chuck is rammed into the surface of material OR if the material is hollow, like a tube or partition, the point of the drill can damage the opposite side of the cavity. Anybody know what causes this? I can't find any markings on the drill packaging that would explain if this is a different type of drill so I don't know where to find drills that don't do this.

Nice job, thanks!

The refurbished sharpener looks beautiful now.

Very well practically explained ...

Thank you! It was very informative.

Outstanding ! Thank you .

Thanks for this well presented, valuable information.

A lot of my is/was working with brass. Here a sharp bit would grab the metal and I would need to find different ways to polish the final hole. Then I was shone a way to modify drills just for brass. I would flatten the lip, so to speak. While the clearance angle remained the same the lip ''wedge'' angle was lessened. If this makes sense. You would be filing the lip flatter, less than 90 degs.

Thank you. Very helpful.

So many YT creators poo poo the Drill Doctor, bit grinder. These same people have spotty, at best, knowledge of proper drill geometry. You sir, are way more knowledgeable than most tool users! Good topical overview of bit geometry. Perhaps you could create a third video, advanced drill bit grinding techniques and when they are appropriate. Cheers

Man that looks great! Thanks for the lessons on the geometry of a drill bit, a lot of stuff I didn't know! Great video, can some one link me the hand sharpening video Mr.Pete mentioned ? I cant seem to find it

Mr. Pete, any chance of covering wen thinning in the series? If you combined that with the other lessons you have planned, it would make a good dvd course.

Excellent video, as always. I have a question and an observation. Question: Some drills I purchase new do not have a distinct margin visible. I suppose on those bits there is a gradual taper back from the margin in the land area. Is that the case? Observation: The faceted method, which you showed a botched example of, is actually proclaimed by some off hand sharpeners of drills (not that I agree) due to ease and speed of getting a dull drill to cut again. I suppose these are the hammer and chisel mechanics you often mention.

Great video. Has anyone ever heard of thinning the web? Many years ago I worked in an automatic screw machine department in Pickens SC at the now defunct Singer plant. The plant made Craftsman Power Tools. This old tool and die man would hand sharpen and thin the web and the bits would last longer. I don't know why. Perhaps coolant got to the tip better. Keep up the great videos.

THANK YOU...for sharing.

I was dying to see you reveal your face in that photo! Please show some of these pictures in future videos!!

"There are two methods used for web thinning. One method requires a round edge wheel; the other requires a square edge wheel. A round edge wheel will work in the flutes of the drill and follow the natural contour more readily than a square edge wheel. However, it is always necessary to grind the cutting edges straight after thinning the web on a round wheel, as the wheel will grind into the cutting edge. If a square edge wheel is used, thinning of the web is accomplished by grinding away the back portion, or heel, of each cutting lip. This will result in removal of a portion of the twist near the end of the drill; but will accomplish the purpose fo reducing the web thickness satisfactorily" (How to sharpen, 1954. pg. 28.)

Learned so much lyle

Mr. Peterson, would love to see more about your teaching aids. Also, like to hear how you made the 10X drill bit teaching aid. How about showing the picture of you with it rather than covering it up? Did you have a big pimple the day you had the picture taken with the drill bit teaching aid (back when you were still a teenager)?

God bless you sir .I am sitting for exam in foreseeable future. Excellent video

Thanks for sharing sir..

Great information sir

Outstanding video mrpete. but i now miss the claw hammer / hatch action.

Mr. Pete... I grew up in a machine shop my father was a machinist tool and die maker as well as my brother I have been shown many times how to sharpen a drill almost verbatim of your video by my father or my brother.. my father could sharpen a drill free-handed and it would be the sharpest drill of the bunch.. my brother could make do free handed but mostly relied on a machine such as yours.. I on the other hand understand the geometry, understand the angles, understand the reliefs, I know what drills to use how to use them with coolant or with oil, Ect Ect if I use a machine I can generally get a decently sharp drill but for the life of me I cannot free hand sharpening a drill I'm 52 years old I've been doing this since I was 7 and I cannot put an edge on a drill free-handed... To me someone who can sharpen a drill free handed has a talent... My father, God Rest his soul spent many hours trying to show me and to this day I just can't do it but I appreciate your videos and I always watch because I may learn something new everyone has a unique way and I like watching other people because you can learn from them so thank you very much for your videos looking forward to more

Very well explained for common man ! If that book ,"The use and care of TWIST DRILLS " is not longer published it will a real benefit if it was scanned and put in public use !

Thanks teacher.

That "Engineer's Black Book" is a great reference. If you get one, don't forget to go to their website and enter in the code on the little hologram sticker in the back (along with your thoughts about the book) and they'll send you a drill and tap size wall chart for free.

Hi Drilling quotation Do you know breakthrough space under plate for drill how much it is say for 1 inch drill ?

Thanks!!!

Question. at around the 08:40 mark, you mention the thickness of the web. When the web gets too thick, it won't cut so we should "pre-drill" the hole. I do a lot of "pre-drilling in my various materials. So when we "pre-drill" a hole with a pilot drill, should we select a pilot drill with a diameter that is about the same thickness as the web?

Mrpete is correct that sharpening a standard twist drill smaller than 1/4" (6 mm) by hand rapidly becomes very difficult to do by hand as the diameter decreases.The difficulty is that the web thickness as a proportion of the diameter is greater in small drills. You have the same problem sharpening a larger diameter drill that has been cut off short. The web is thicker so that web thinning is needed...a nearly impossible task by hand with a small drill on a bench grinder. It's usually cheaper to just by a packet of small twist drills in the size you need and discard them when they become dull. That's not as bad as it sounds, because if you take the time to use a twist drill with the correct speed, feed, and coolant (if required) it will work satisfactorily for a surprisingly long time. If you are drilling difficult materials this is even more important. Realizing that the drill is beginning to dull makes resharpening it much easier and faster. In smaller sizes, it avoids snapping the drill off and possibly spoiling the work.

its a bit of an art to correctly sharpen a drill bit. also, as you may know, if one doesnt have a drill gage, one can take two nuts, perhaps at least 1/2" dia, put two flats together and there you have a 60 degree perfect angle to check your cutting end progress in a pinch.

If you lack the drill gauge, you can confirm equality in your grind using one of your ruled adjustable squares ... if you know what to look for. That might be something to cover later on.

I learn so much from you i am worried about it pushing things out. My wife says i am full of it.... i assume she means wisdom.

Enjoy the video thanks sir for that 👍👍👍👍👍👏👏👏👏👏🌹🌺⚘🌷

The only reason I have ever intentionally ground uneven lips for an oversize hole (16:10) is when I didn't have the correct tap drill available. Not ideal, but can get close enough.