Sharpen A Gundrill

How I sharpen a gun drill using a Accu-Finish Grinder

[@howardwilliamson4076]

Thanks so much for doing this video ! I'm a home shop hobbyist - in the midst of building a deep hole drill /rifling machine for making rifle barrels. Completely new to gun drills - I have a grand total of one ! My nearest supplier is a couple thousand miles away and I didn't like the thought of sending drills back to have them sharpened - now I can see how I can do it in my own shop.Nicely done video - clear and concise - I learned a lot - Thanks again

[@EdgePrecision]

Thanks Its always good to hear.

[@aceroadholder2185]

Pretty soon you are going to find out why drilling rifle barrels was already a specialty in the 1700's. For the effort involved, unless you couldn't live without making your own barrels, I'd go buy one that is straight and correctly rifled.

[@douglaslodge8580]

You sir are a true craftsman. I have watched all your videos and this last series is absolutely amazing.Your dedication to precision is awe inspiring.

[@cncdavenz]

looks like you take on a lot of jobs that many other would shy away from. Thanks for the very interesting videos.

[@ivanthehunter]

Thats the best video I have see on gun drill and explaining how they work

[@lorenlieder9789]

Great video Peter very interesting subject on gun drills and how you sharpen them.

[@Anonukin91]

Nice video, i work everyday with these drills..just much more longer drills. 1750mm long. They are really easy to sharpen when you have the right tools.

[@pawankashav54]

Plz send Hindi lauage

[@billdlv]

Nice job Peter I didn't know the Accu-Finish had those attachments, they look really useful. That part looked really good reminds me of my aerospace days. I'm reading some of the comments; trial and error take on a whole different meaning when working with such expensive raw materials, and the usual impossible schedules and deadlines.

[@norcosawllc9248]

Not a bad edge for grinding manually. It's a real must though to have a comparator to find and center those cutting geometries. Thanks for sharing your videos.👌

[@EdgePrecision]

It can be done with a pair of calipers and a magnifying glass. I have done it that way before. Thanks!

[@RRINTHESHOP]

Nice demo on the Gun drill. Beautiful part.

[@fryydcamel]

Cheers man I’ve been gundrilling exclusively for 8 years now. It’s quite the niche to get into 🤙 (edit… I use the same sharpening machine !)

[@floodo1]

no actual machining but still one of the best machining videos! Super interesting and we get to see that completed part ... i'd been wondering what it looked like all finished! Thanks

[@Skyisnotalimit]

That kind of drills i used to have in a German “Tief Bohr” machine. The drills was in pair, could do 300mm very fast. There was a lot of a special oil pressurized through with a big pump to have materials pushed out into a bin with a net, to catch the chips and let the oil back into the filter and oil tank. You have very good videos. Thanks!

[@EdgePrecision]

Thank you! Yes actual oil for coolant is the best for gun drilling and volume is actually more important then pressure. But of course if you push a lot of volume in a small coolant hole it will increase the pressure to high pressure.

[@pieterveenders9793]

@@EdgePrecision I thought pressure is needed over volume, as pressure will help break up the swarf and not form long lints.

[@EdgePrecision]

@@pieterveenders9793 For small drills the coolant holes a so small that a lot of volume of coolant will increase pressure. But as the drill gets larger with larger coolant holes even if you have a high pressure coolant system you will never get to the high pressure because the holes in the drill are to large. So in this case you need the volume to get there. I have found it is harder to drill holes above 1/2” in diameter than smaller holes because of the lack of volume in my coolant systems.

[@cvantrease1231]

Very cool I wish I would’ve seen this when I was learning tool cutter grinding Awesome visuals

[@davidjackson4112]

Thank you for sharing your talent.

[@pedrorivera4769]

that grinding machine sharped easier than my old machine when i grinded tools

[@Edge2219]

Awesome! I know who to send my gun drills to for sharpening. No worries I dont even have a gun drill ha ha. They do work good for deep hole drilling like you say though. I worked for a guy that was a manufacture of duck and goose calls and we used them in Acrylic, worked great and a good finish!

[@michaelj.blount1446]

Good Job ! Well Explained. Well Presented.

[@danvandertorre9280]

cool now I know how to make that sharpener with all the angels and speed thanks for the info .

[@James-fs4rn]

you do some really nice work just to state the obvious. thanks for sharing.

[@theessexhunter1305]

Again fantastic work with great description

[@mrrrrr1rob590]

First of your videos I've watched. Earned my sub! Quality work, nice machinery, and knowledge.

[@brianbures4478]

Your videos are great and very knowledgeable!!!

[@ls2005019227]

Very interesting video! Definitely not much on YT about gun drills.

[@trif55]

I found this, I'd never known how such small holes were bored so consistently and found very little info, beyond the term gun drill, this at least goes into some detail about how they work, it still amazes me they cut straight to such depth!

[@pierresgarage2687]

Good explanation about gun drills... ;) Maybe try the manual focussing feature with your camera, it helps a lot where auto focus isn't keeping up...

[@EdgePrecision]

Thanks. Yes the camera I had that day is this Canon G7X MRK II. The more I use that camera the less I like it, but it is small. It also has no audio input jack. The manual focus on that camera works terrible. In other words I cant stand it. I would like to purchase a Canon 6D MRK II. I have the previous version of this camera and many lenses. In particular the 100 MM macro f 2.8 would work good. The previous version of the 6D is not as video friendly. No flip out LCD screen so it requires a monitor. Also I would like to use my better lenses. Than the 6D requires a bigger tripod and so on. It never ends. A new GoPro first than this.

[@pierresgarage2687]

Not as nice a picture as an SLR camera, but for video only the Vixia sereis is doing an honest job for around 2 to 300$, that's what I use, it has an external mic input, manual focus, macro, Zoom, you maybe want an extra wide angle adaptor. I'm machining, grinding and welding, so, I'm not ready to spend a fortune in cameras in that environment, beware of grinding mostly as it will instantly ruin a lens, or later with dust and chips... My opinion about GoPros is quite negative, 2 words, Overpriced junk... ;) Also a side of the mouts close pick up microphone is helping A LOT to make speach more legible in a noisy shop environment. Keep on the good work... Pierre

[@justinmoritz6543]

24:14 Hey this looks like the mating piece to the titanium piece you just made!! Key way and all of the holes on the one end.

[@Skyblue-p7h]

Thank you for such a informative video .

[@PeteBrubaker]

Very cool stuff man! You might consider some WD-40 on that diamond wheel. I've ground a lot of carbide scraper blades and the light lubricant helps to flush the swarf out of the grains of the plate. A good spray with a WD-40 spray bottle will wash out a lot, and I always apply a little when I first start grinding.

[@danvandertorre9280]

your right pete its also good for cleaning out honing stones that go black with particle's.

[@craigwalker3256]

love your videos. thankyou for sharing!

[@drubradley8821]

Nice work on the finished part from the last video. As per, this video, I am sorry to keep bugging you on the whole game of "GUN DRILLING" and all that pertains to this art form, but, I am really fascinated by this process. My question this week, I kindly request, can you look in your Machinist's hand book, as I will assume that with all the lovely and costly toys you have at your disposal at your shop, that your Machinist's hand book is with in the past few years ,and likely this years new addition, where as I am still using my vintage addition, (American Machinists' Handbook by Colvin and Stanley, EIGHTH EDITION, "1945",) lol, Yes, I know how pathetic I am, but, I can't afford a new copy even used, they are costly, and I do keep my eyes open for a used copy of newer editions in the second hand stores... Anyhow, Can you look in your hand book, to see if the new editions, of the past 10 to 20 years worth, if they cover gun drilling, and theory, and I think I can use the word "nomenclature" of the gun drill's optimum design(s)... As, my old 8th edition, although full of great stuff that I do reference to very often, weekly, does not cover any such thing. If the new editions do cover this topic, I think, that would assist in me sacrificing something else, so I could put forth the money on a newer handbook. There is no hurry upon my request, just the next time you are rummaging through for other info, I kindly request to take a peek to see if they do cover the topic. Nice job on this video here. As I mentioned in a previous video, where you were using the gun drills, I mentioned that there isn't really much out there upon the matter, and any of the science is protected by the company's. The manufactures, will not talk (waste their time) on some small guy like me, unless I did an opening order of a few thousand dollars, which, I totally respect and understand. I will also respect and understand 100% if you are in the same boat, or simply just do not have the time. I will still appreciate all the info that you have already shared, and I am content for that amount. BUT.... the more you teach, the more I want to know about the process, LOL... Thank you, again, fine job on the video, Drew

[@EdgePrecision]

Dru Bradley My version of the machinery's handbook is the 21st addition it has no information on gun drilling. Most of what I know I learned by trial and error. There is very little information on the subject. I think the people that do it like to keep it that way.

[@drubradley8821]

Roger that. I do understand the idea of keeping a trade secret in house. The idea, that a company has went through all the costly trials & errors, to then just hand out this info for free... But, I really do appreciate what you have taught so far, really good stuff. Thank you, Boss. Drew

[@JaakkoF]

Call Sterling or Gühring and you get all the info you need for feeds, speeds, materials, coolants etc. They are there to do business of selling gun drills and are more than happy to share gundrilling information.

[@lohikarhu734]

Can you use a gun drill with just air flow to cool, and clear chips, if you drill more slowly? Or, do you care very much, with sold carbide gun drills?? Thanks for these videos, sir! BTW, Hammond (UK) suggest using water-soluble lubricant with their gun drills, 10% solution...different dimensions/finish/geometry??

[@EdgePrecision]

Thanks Lohi Kartu. There is a system that uses a air mist coolant system with a gun drill. I think Adam Booth showed it once a long time ago on his channel. I have never done it that way. You can use water soluble coolant for smaller drills (It's what I use at a 10% solution). But I find for larger ones it does what I showed in this video. All commercial drillers I have seen use oil for coolant.

[@juandelaluz2196]

Do you ever run a gun drill at the manufacturer's recommended feeds and speeds?

[@EdgePrecision]

In truth I don't know what the manufacture feeds and speeds are. I just do what has worked for me in the past. I feel that if you don't have the exact same setup, coolant, coolant supply and pressure what they are recommending may not work. Now if you do than by all means do it their way. But usually they are using oil for coolant. Not water soluble coolant and that make a world of difference when gun drilling.

[@scottlundy257]

You sure make some nice parts

[@thrustprop67]

that was so interesting,, never knew how the drills were re sharpened

[@XinPaotau]

VERY nice job )

[@qamarraza5382]

Sir i have 500mm length and 15 mm diameter . This diameter can not clamp with steady rest. Please gave an idea for how can i control chattering?

[@EdgePrecision]

I’m not sure I understand your question. This video is about a gundrill. Are you referring to that? Or are you asking about turning a 15 x 500 mm in a lathe?

[@akfarmboy49]

that is a busy part. thank you

[@ray-charc3131]

How about the EDM drilling method。 It tends to has high accuracy because there is no machining force interaction during the deep hole cutting。 The downside is the matt edm surface finish remain and the process cannot be happened in the same machine set up。

[@EdgePrecision]

raychar cheung Also it may come down to the size of the part. Will it fit in the EDM machine with a long electrode.

[@chapiit08]

Very interesting video. Who manufactures the gun drills you regularly use?

[@EdgePrecision]

I mostly use Drill Master drills. But I do also have some Star brand and Eldorado as well.

[@chapiit08]

@@EdgePrecision Thank you!

[@normanj844]

Great video Peter! Neat to see the pitfalls of gundrills, not much info out there about them. For sharpening twist drills, do you use the Darex? What would you recommend? Also, thanks for showing that finished titanium part, a shame you couldn't film more of it.

[@EdgePrecision]

Norman J Yes I do use that Darex grinder quit a bit. That models main weakness is it's chuck that holds the drill. You have to tighten it as tight as you can or the drill will slip. A friend of mine has their more expensive model it's much better but it costs three times as much.

[@JaakkoF]

There's one saying I like to use: don't cut corners with tool purchases, that's the wrong place to make savings from.

[@SpringfieldM1A]

I've got a job coming up gun drilling a hole through inconel 718. Hole is just under 0.3" but I have to go 28" deep. How many inches are you getting between grinds in this material? 718 is pretty spendy stuff, don't want to wreck it or the drill. Don't mind re-grinding after each workpiece but it will be a nuisance if I have to re-grind during the cycle. Do you think I could make it through on the one grind? I do have a counter rotating machine with cutting oil etc. Any help would be much appreciated.

[@EdgePrecision]

You will have to experiment. Drill part way and look at the drill tip. If ok drill some more. It would not surprise me if you had to sharpen the drill before going 28” deep. What I usually do is have a short drill drill half way a d finish with a longer drill. If you are doing many parts. I would have more than one set of drills. That way I could sharpen them while drilling with the other ones. Gun drilling takes time. So you will have time to sharpen drills while others are drilling. Listen to the sound of the drill and look at the shaving coming out. Also I keep a eye on how the coolant is exiting the drill. That tells you a lot on how the drill is drilling. Don’t know if any of that helps. You will just have to experiment to get things right. One thing don’t try to feed the drill to fast. I usually run in inconell around 110 surface speed and around .0005” per rev. But I’m using water soluble coolant. With oil you may be able to go a little faster.

[@SpringfieldM1A]

@@EdgePrecision Thanks very much and thanks for taking the time to share your videos. They're all good stuff

[@philgarbarini9645]

Great video.

[@nathantownend1233]

Hi any tips on stopping the gun drill from wandering when drill deep hole over 1500mm

[@EdgePrecision]

I have never personally drilled holes that deep. I have drilled small diameter holes fairly deep. Lets say a .203" dia. drill 18" thru parts. Whenever I do this kind of thing. I start with a short gundrill making sure to get the hole starting straight. Then increase the drill length in stages. In other words don't try to drill it all with one long drill. Also I thing it is important to keep the drill sharp and properly sharpened to balance the forces on the drill. Parts here where we need drilled holes that are straight we send to people who specialize in doing this. (Dearborn Inc. is one) I posted a photo on Instagram showing a part around six feet long with .218 dia holes drilled thru it's entire length. They can do this but they are very secretive about how it's done.

[@adsdentiste]

Lovely music

[@brettw.3128]

Are the angles you use when sharpening the drill universal for most drills on all types of material or?

[@EdgePrecision]

I have used these same angles for pretty much everything. They do change slightly for drills under .100” in diameter.

[@roddelmundo6560]

I know how to Regrind that Gundrill Tool. the Right Angle. its part of my Job.

[@tomharrell1954]

Thanks great lessons

[@a.k.2023]

Nice Video like your other Peter. I have build a kind auf gun drill grinding machine for our grinding shop in Germany. How much cost your machine? Can you grind 5 mm or more if the drinn needs this?

[@EdgePrecision]

I the machine’s current cost are posted on their web site accu-finish. com. If I were you I would just buy the machine. If you grind quite a few gun drills you will need some different grit wheels and have to replace them when they wear out. They can supply all that from stock. I have ground drills from .062” in diameter to 1”. You will need fine wheels for small drills, say 600 grit. For large drills 240-400 grit depending on size. They also sell off hand bench grinding wheels which I also use in a bench grinder to rough a lot off. If the drill has a big chip in the tip.

[@a.k.2023]

Edge Precision ok i will look on this side! Thanks! Like your Videos and had subcribe your channel. Axel

[@richiejbhoy1888]

I think you are suppose to turn the wheel the other direction depending on which side you are using.

[@EdgePrecision]

I have found when grinding the angles on the right side of the plate. You are doing heavier grinding. So running the wheel up reduces the chatter. Also it takes less time because you don’t have to stop the spindle and reverse it. This machine won’t instantly reverse. First you must stop it than push the reverse switch. There might be a argument that it would be better to grind down toward the cutting edge. That is true but I have found it makes no difference that I can discern.

[@richiejbhoy1888]

Edge Precision yeah i agree the waiting for the wheel to stop before reverse works is a pain. I think the arguments i seen was it gives the tool more life when done the way the manual says. Unlikely statement. Haha

[@jimsvideos7201]

I have no idea what that titanium piece is, but damned if it wouldn't look good sitting on some acrylic v-blocks on my coffee table.

[@TiênĐăngvăn-w4c]

Mũi khoan dài bán ko

[@skirifles2076]

Very cool vid again Peter. Two questions.... 1. I have about 6 BNIB gun drills that I will not use. I want to give them away to someone that can use them, are you interested? 2. The part you machined looked like it had a male key way machined inside of it. How did you machine that? Thanks....SKI

[@EdgePrecision]

ski rifles The part had the key burned in a EDM machine. As to the gun drills I need more information what size and how long are they?

[@skirifles2076]

Edge Precision ....Thanks for the reply. I was assuming EDM but wasn't sure. The drills are about 3' long. I will have exact sizes tomorrow. I will email you. Thanks again.

[@tomharrell1954]

It does not make any difference but if you can please tell what the parts do. Like oil well cutting head or what ever

[@jeffreypfeifer862]

Super helpful information! subscribed now too!

[@ewotha2]

Why don't you spray any lapping fluid on the wheel? Think of a pedestal grinder that has coolant sprayed on the wheel.

[@EdgePrecision]

According to Accu-Finish the people that make the grinder its not necessary. I have tried it all it does I just make a big mess for no real reason. I have been doing it this way for many (Over 20) years and in all that time only bought about three new wheels to replace worn out ones. This grinder turns at a very low RPM(I think about 400 RPM). There is very little to no heat even when bearing down hard on the wheel.

[@mva8082]

my old boss always would use the accu-finish grinder for some reason he put a little wd-40 when sharpening the tools on the diamond wheel he would get pissed when you didn't use any wd40 during sharpening what is your opinion on this peter????

[@EdgePrecision]

You don’t need anything on the wheel. Even AccuFinish says that.

[@cruch9]

does gun drilling have to be performed in the horizontal position for chip evacuation? I am assuming it wont work as well if at all in the vertical position?

[@EdgePrecision]

No gun drilling can be done at any angle. The coolant flow and pressure force the shavings down the flute of the drill. I have drilled many holes in the vertical position.

[@cruch9]

Edge Precision thank you very much! Love the videos. Should think about more complex probing videos. I have a large 26" diameter 5 tooth (yes 5 tooth) chain sprocket i have to machine the inner feature but am not sure how to probe it. May have to go old school. Thanks again

[@cooperscreativeconcepts8697]

cruch9 it can be done vertically, that is if the drill is facing up and the piece is lowered onto it. FYI I’ve seen videos of these setups in Italy at the Uberti factory, they’ve got like 3 or 4 gun barrels going at once. This also helps save floor space in a warehouse. Just let gravity and fluid evac those chips out.

[@mrrrrr1rob590]

@@cooperscreativeconcepts8697 My work has a machine being built in Spain now that will change the orientation how we drill and tap the tie rods we manufacture from horizontal to vertical, for the very reason you mentioned. Conservation of shop floor space. It will face to length, drill and tap 2 tie rod ball joints in the realm of 7.5 second cycle time.

[@Dr_Xyzt]

Neat. So, a gun drill is a lot like a trepan tool.

[@EdgePrecision]

Sort of similar just smaller.

[@Sketch1994]

Do you know if there is any grinder attachment for resharpening reamers?

[@phillipharris8277]

I wonder if the erosion is caused by cavitation.

[@meocats]

what do you think about BTA ejector drills? the chips come out through the drill body

[@EdgePrecision]

meocats BTA seems to be a very good process for larger holes but it takes a specialized machine to do it. It's not something your going to do on a standard machine without some very elaborate tooling and coolant system.

[@meocats]

iscar has them starting from 0.500" iirc and external coolant pumps are available if you ever need to drill larger than 1 inch hole. But i was wondering if the holes drill straighter as the heads are more symmetric than a gun drill.

[@EdgePrecision]

meocats Actually because a gun drill only drills on one side doesn't mean the drilling is unbalanced. The tip angles are very important as well as the tips point. That's why I use a optical comparator. These angles balance the force and keep the drill on track. I have no hands on experience with ejector drills. I have seen it done and know a guy that builds them. I think they drill faster but as to straighter I can't say.

[@meocats]

why are they called 'ejector'? what does that mean?

[@EdgePrecision]

Go to this link they can explain better than I could in a comment. btahellerinc.com They also have information on other drilling operation methods. Hover over the drilling systems than click on double tube systems.

[@zmajmr]

interesting part, I wonder for what it is?

[@EdgePrecision]

zmajmr I can't say. Most of the times we as machinist don't find out what we make does.

[@raybrown5890]

perfect!!

[@zhipengduan3520]

Hello sir, are you interested in becoming distributor of gun drill product?

[@EdgePrecision]

Thank you, but no.

[@account0199]

I thought carbide dust from grinding was toxic...

[@EdgePrecision]

It probably is. If you are breathing a lot of it. This slow speed grinder doesn’t thro it into the air. I do get it on my hands but I wash it off right after I finish.

[@account0199]

@@EdgePrecision thanks for the clarification!

[@whitemale6497]

Do you break very many drill bits or pop the carbides off? Do you get much steel collect? And that was a very poor example of sharpening a drill

[@CuongNguyen-ic7dv]

có tiếng việt không bạn

[@EdgePrecision]

xin lỗi không tôi không.

[@오구역]

what is the rpm?

[@EdgePrecision]

Are you asking about the diamond grinder. It turns slow. I don’t know the exact speed. I would guess around 200 rpm.

[@오구역]

thank you very much for quick reply...

[@briangena3049]

sorry I work for bear Creek arsenal I am the set up and the reshaping man on control, we make over 4000000 barrels and yours tecnical is so boring u wanna learn contact us.

[@EdgePrecision]

I tell you what. Than make a video and educate us all.

[@vikasvaishnav1976]

But it is not parmanent solution

[@michaelrodriguez-fb8fr]

absolutely love your channel !!! i would suggest making some tee shirts i would love to buy a couple cheers mikerodwelds

[@vUulve]

Aucun bilingue (franco-anglais) ne serait motivé à traduire les sous-titres ? je suis extrêmement intéressés par toutes ses vidéos mais je comprend rien :(

[@highstreetkillers4377]

Long drill, lol. I didnt know gundrills came so short. I drill holes 3 m deep on compound angle. Used 9\16 twist drill meter deep on compound angle through 6 intersections. It aint hard to drill