WHAT IS COUNTER BORING? short #41 tubalcain counterbores

[@durkhurker6268]

Hey that's not stupid at all! Knowing that there COULD be a difference between cap screws might save us some headscratches if we're working on older machines! 😁 Thanks Mr. Pete, you're a fantastic teacher!

[@mrpete222]

👍👍

[@Hank_Snow]

I concur!

[@haroldsprenkle4173]

Hey, I have ran across this problem, older cap screws sometimes had smaller heads, not a problem for making new holes, but I have had to turn down heads of new shcs's to fit old holes.

[@CA_Rock]

Thank you for the cutaway and for the historic size change on socket head cap screws. I've been stung by what I thought were non standard sizes on socket head cap screws on old machines, but now I know the size standard changed.

[@mrpete222]

😄😄

[@mikemerritt8496]

Hi Mr. Pete. Another great video. I am not a machinist. I do have a small shop at home and enjoy making things. I did take machine shop in high school and always think about my career choice machinist or mechanic. My grandfather was a machinist and had a small shop. I did get some of his tools and I use them everyday. One machine is an old sears 101 lathe which I am restoring. Over the years of being a mechanic I worked on cars, trucks, heavy equipment and hybrid buses. I'm sure if I would have been a machinist I would have enjoyed that career also. Now I retired and am having so much fun and learning new things. I did buy a standard and metric set of counterbores. I like measuring the head diameter and using one that fits best. I did a few projects where the hole was to big. Thanks again. Mike.

[@mrpete222]

👍👍👍

[@4GSR]

We always referred to the old style as the "1956" series socket head cap screws. Encountered lots of them over the years! And still do, working on some of my older machine tools. As always thanks for sharing! Ken

[@larry400]

Definitely not a boring subject and video, which is a bit counter to the topic. So counter confused.

[@LostAgain1970]

The joy of your "short" videos are the side tracks you always get into. I'm loving it! 😁👍

[@mrpete222]

😄😄

[@RRINTHESHOP]

Great coverage of the counterbore subject. Very helpful.

[@mrpete222]

😄

[@josephstlouis]

I thought shorts meant 1 minute? Maybe Mr. Peter is wearing shorts? If he was a preacher I'd recommend bringing a lunch pail to church🙏. Whatever the case don't we all love Mr. Peterson, "as we addressed our seniors back in the day". Yep I'm from the mid 50s. Thanks for all your entertainment, ranting, and sharing machining knowledge. 👌

[@StanErvin-yo9vl]

He's not all that tall, I guess @

[@emerycreek8016]

Thanks for the lesson Mr. Pete! Loved the bolt head comparison too.

[@mrpete222]

😄

[@daveharriman2756]

A very enjoyable watch, here in England the 1/4 whit cap screw has a 3/16" hex key socket. with the same 20 TPI thread as your UNC 1/4" but 55 degrees instead of 60 degrees, wow that took longer to type than your video!, cheers Dave

[@mrpete222]

👍

[@johncloar1692]

I always enjoy your video. There is a lot of wisdom in your videos. Thanks Mr. Pete for the always enjoyable videos.

[@mrpete222]

😄😄

[@russellherold272]

I sure enjoy your shorts. I am 78 and not too old to learn from your valuable information and knowledge. I teach electrical theory at our community college but spend more time in the machine shop. Hurray for you!!!! Bless your heart.

[@renaissanceman7145]

I have a Bridgeport but no counter bores. If I need to counter bore I drill then thread if needed then counter bore with an appropriately sized endmill watching the DRO. Once I've finished I'll then move to the next hole.

[@mrpete222]

👍

[@robertpearson8798]

I think that that’s what most of us hobbyists do, although I think I might acquire a small set of counterbores for my most used sizes to save a bit of time and effort.

[@kensherwin4544]

Thank you for the extra extra credit opportunity. I'm such a slow student that I need all the extra credit I can get to be able to graduate before I grow up and get expelled.

[@mrpete222]

lol

[@llapmsp]

Very interesting topic. When I received my shop training at work, I had to drill a partial bore hole then re grind the drill bit to cut a flat bottom. Then when done with the counter bore, re sharpen the drill bit by hand on a pedestal grinder. Then drill a hole, supervised by the instructor to prove I could sharpen a drill bit correctly. I was so happy when he let us use counter bore bits. Sorry for the rant but I couldn't pass up telling my story. Thanks for all that you do.

[@mrpete222]

👍👍👍

[@dannyl2598]

Thank you Mr Pete. That was very informative and very enjoyable. Have a great weekend.

[@Wooley689]

Very informative video, even the cap screw info. Restoring an antique vehicle would garner extra points for having the period correct screws.

[@mrpete222]

👍

[@parkerackley133]

I have a copy of a 1918 Machinery's Handbook. It contains the dimensions of hardware of the time. Most has changed over the years, especially the head and nut dimensions. It is also very useful to see the normal practice of the time. Many things have changed over the past 100+ years.

[@sethemerson885]

I have been using two unusual counterbores for several years. Well, both are unusual uses, only one is an unusual tool. I relocate the fuel jet in certain carburetors to prevent high cornering speeds from pulling fuel away from the fuel feed position. I have to move the jet to a place where the float of the carb might hit it, or maybe actually catch on it. My procedure is to bore through to the main fuel location, then counterbore the hole to allow the jet to be recessed into the wall of the chamber, after that, I tap the hole to allow the jet to screw into place away from the float. I used to use a standard counterbore tool in a drill press, now I use my Bridgeport. The second counterbore tool is unusual (and was expensive). I am slightly changing/relocating the bolt pattern on "mag" wheels to allow them to be swapped onto another brand of car. Just a tiny bit. At the same time, I machine the hole to install a steel tapered insert for each hole. The special counterbore tool has a cutting tip that bores a larger hole in the correct location, again just a little offset from the original hole. As the hole is drilled, the tool's shoulder eventually contacts and then cuts a new concentric tapered seat, contoured for the insert profile. This large counterboring tool was obviously made from a large drill. After I locate and drill the new holes, I remove the wheel from the Bridgeport table and pull in the inserts. I used to pay shops to do this, now my Bridgeport does the job!

[@mrpete222]

Very interesting uses for a counterbore thank you

[@carrollprice1213]

Thanks for another educational video. Have observed and used counterbore screws for years but never stopped to consider how they're made.

[@rexmyers991]

As always, I learned a lot. You are an EXCELLENT teacher.

[@mrpete222]

😄

[@joewhitney4097]

Great video, I learned something new today. I have not run into the issue of different size heads before that I remember but good to know about the issue. Thanks for sharing.

[@strongandco]

For years I never even knew these existed. (for context, we don't do any sort of production work) counter boring operations were always done on a milling machine using a slot drill right after drilling the associated hole. Had I known about these, there would have been times when I'd probably wish I had a set of these handy little gadgets.😄

[@mrpete222]

👍

[@arlindkrasniqi3315]

Amazing video. Thank you mr. Pete, very very educational and sprinkled in the mix is just the right amount of entertainment.

[@haroldsprenkle4173]

Hey Pete, good video as usual. Shop where I work, die shop, generally 1/64 or 1/32 over pilot diameters. Most of our die sections are 1/32 over on fasteners. Our complete set is 1/32 over. Then enters the "engineers" they spec anything and everything for counterbores, guess it is off the top of their head or what the CAD program popped up. Ok I use my head, kinda, measure heads of shcs etc. Cut off more than a few drill bits to make odd counterbores for print drawers. There are specs for this stuff, don't these guys ever look, heck they call out drill diameters that aren't on any charts, not going to bore a diameter for a simple bolt to go through. Gee. I am starting a rant like someone I know. One of our engineeringnerds specs .562 deep holes through .5 thick materials instead of thru. Old guy I work with, hey he is 76, I am only 61, he showed me on print, told him just bring quill down further, make sure. Ha. Hey gotta add one, counter bores are wonderful tools, but if you are working with a homemade flat bottom bit chopped off and hand ground. Bridgeport or clone spindles have just enough backlash on quill to chatter, lock quill and feed with knee. Hey Pete, keep making videos. PS, you aren't the only one that can do a rant.

[@mrpete222]

Very interesting

[@MrUbiquitousTech]

Excellent video Mr. Pete! I've always liked the way cap screws and counter bores look. All of your information is great, I always watch the whole video.

[@theElderberryFarmer]

Thanks very much for this informative presentation, Mr. Pete! This kind of instruction is so very lacking in today's world. Take care and God Bless.

[@mrpete222]

Thank you very much

[@jodydoakes8754]

Yes, enjoyed. Yes, found very interesting. I have been around for a hundred years, give or take, and have always counterbored with a drill. Never knew there were special tools! Sheltered existence.

[@mrpete222]

Thanks for a very very interesting comment.

[@hawkenman.549]

Love your videos, always learn a lot from you. Thank you Mr. Pete.

[@mrpete222]

😄

[@kevinnobody3052]

Thanks Mr. Pete. I find these topics very interesting. I might be kinda boring..... But I'm also knowledgeable. I thank you for that.

[@mrpete222]

😄

[@andyjohn5272]

Hi Mr Pete, Id be interested in how to go about sharpening one of these counterbores and if you don't have one the right size on hand is it feasible to grind an old drill down to size. Looking forward to your video on spot facing. Keep up the good work!

[@cschwad559]

I do it all the time. Surface grinder is your friend on that one.

[@orangetruckman]

Thank you for another great video! I’ve come across the different sizes Allen heads before and didn’t know why they were different. Now I know, thank you sir.

[@mrpete222]

😄😄

[@familyd5952]

Good Morning Mr Pete!!! The Tennessee Mole Man 👍🇺🇸🍊🍊🍊

[@mrpete222]

😄😄

[@peteengard9966]

I ran into the two different head sizes on a truck steering gear once. Thought I was losing my mind when the Allen wrench fit one screw and not the others.

[@mrpete222]

Yes

[@daviddickson7067]

Thanks for the wartime trivia! I like to know things like that.

[@mrpete222]

👍

[@davehiggins5903]

The whole class was very interested

[@mrpete222]

Thanks

[@DonDegidio]

Hi Lyle, You can also use pilot point drills to make a flat bottom counterbore. I have a set of DeWalt pilot point drills and have made counterbored holes by first drilling the counterbore and then coming back with the through hole size. You and your family have a safe Memorial Day weekend.

[@mrpete222]

👍

[@paulhunt598]

I had to counter bore 2 days ago. This was the first counter bore job requirement since setting up my new hobby shop 1.5 years ago. Industrial machinery is nearly exclusively assembled with SHCS. this hardware is most commonly harder than HHS hardware and fastener and wrench clearance space requirement is much smaller. "Flush" fastener appearance is also much cleaner and is often an industrial look design element as well. While conventional wrenches and sockets were a must tool demand for this industrial maintenance technician, I vastly used hex wrenches more. For this reason, I own every hex wrench, socket, T handle, screw driver handle, power bit style manufactured in both standard and metric, plus quite a few custom fabricated versions for special application. Until working with these fasteners on a daily basis I didn't appreciate their value. I think that counter boring best practice is to break the corner at the top of the counter bore hole. There are applications where this may conflict with a design element, but the square corner can be quite sharp.

[@hughdanaher2758]

Mr. Pete: never dull or boring 😊

[@AmateurRedneckWorkshop]

Before I got some counter bores I used an end mill t make a flat botton counter sunk hole. Thanks for the video keep on keeping on.

[@henryneyens5066]

I enjoyed the extra extra credit!

[@mrpete222]

👍

[@VintageGearMan]

This is great! I always wondered how this was done so accurately.

[@PatchManMary20]

Great video Mr. Peterson! I always learn something from you!

[@ChimeraActual]

Boat carpenters also use counterbores to create room for a wood plug over a flathead wood screw to seal it from water or for cosmetic effect. I'm most familiar with Fuller taper bits with a depth adjustable counterbore set by a pair of set screws. Excellent video as always.

[@mrpete222]

👍👍

[@pault4513]

As a heavy duty mechanic i used to cut counter bores on engine blocks in order to get the proper cylinder sealing and protrusion above the block after cutting the counter bore i would shim up the cylinder sleeves to obtain .003-.006 protrusion which keeps coolant in the block from leaking and head gaskets so they seal correctly

[@frogandspanner]

Here in UK I only ever use metric allen screws these days. But you have made me wonder, so I'll have a look at the allen screws on my 1966 Norton 650SS. The problem there is that most British bike threads of that age are cycle (steel on steel) or Whitworth coarse (steel studs into Aluminium), so they do not map to US threads and their associated socket size. (If anybody can point me to a formula I can use to calculate Whitworth/BS spanner across-flats dimensions based on bolt/screw size I'd appreciate it.)

[@mrpete222]

Sorry, I can’t help you with that. But we sure did like those Norton, BSA, and triumph motorcycles here in the Illinois Valley. I had a friend that had an Ariel Square four or is it an aerial foursquare?

[@frogandspanner]

@@mrpete222 I worked for many years near where the Ariel factory had been. I taught at Birmingham University, and Ariel had been in Grange Road - just over the Bournbrook, adjacent to the Westley Richards shotgun works. All of that is now student residences - the UK decided years ago it didn't want to make anything any more.

[@danermer2955]

Neat to know how screws have changed over the years.

[@Unrivaledanime]

Thank you Mr Pete i do enjoy your videos

[@mrpete222]

👍👍

[@ellieprice363]

If you’re already on a milling machine with limited room you can counterbore your drilled holes with an end mill.

[@mrpete222]

I am sorry I did not mention that in the video

[@ellieprice363]

@@mrpete222 No worries. You can’t think of everything. Keep on educating us with your vast knowledge of useful tools and operations.

[@vicchiapetta4166]

Hi Mr. Pete, I was in Huntley I’ll this past week for a friends Mothers surprise Birthday party!! I was thinking of trying to get a hold of you, but I was so pulled in so many directions, it made my head spin!!! I don’t get a chance very often to come back from Ca., but I really would consider it an honor to finally meet you!! I have always admired you and the awesome videos you produce!! Thanks as always, Mt. Pete!! Your Friend, Vic Chiapetta!!!

[@mrpete222]

👍👍👍👍👍

[@neatmachine]

Thanks for all of your great and informative videos!

[@mrpete222]

Glad you like them!

[@nelsonmachineshop2032]

i've always liked your videos. i have seen the cap screws , but didnt know which years were different . Thanks for all the videos.

[@mrpete222]

😄

[@rodbennett4790]

G'day Tubalcain. Definitely interesting. Not stupid things.

[@componenx]

I have dozens of counterbores, many of weird sizes, but when I need a specific size/pilot configuration, I rarely have it! I've made many pilots over the years (small sizes), but learned that if the fit is too good, they sometimes catch and self destruct. A great way to get a tight fit if you need one is to drill an under sized pilot hole, counterbore the hole and then drill/ream the pilot hole to the size you need.

[@mrpete222]

👍👍

[@the56bear]

Thanks for interesting lesson. I sometimes use counterbores, but first time seeing a talk on them.

[@mrpete222]

👍

[@RyanWeishalla]

I have some counterbores from auction sales. I've also used milling cutters to counterbore to get the flat bottom, then just have to make sure the milling cutter doesn't have too much radius versus the hardware used.

[@bcbloc02]

Don’t forget backfacing! Then there is also backfacing counterbores which is actually quite common on large parts as often the machined flange side provides the only short access.

[@mrpete222]

I believe i show that tool in the follow up video about spot facing

[@thomasmurray3212]

Mr. Pete: Thank You for another informative video.

[@mrpete222]

😄

[@angelramos-2005]

Very clear explanation,mrpete.See you next time.Thank you.

[@warrenlee3113]

That’s a great video Mr Pete. I don’t know how much about counter boring, I can’t wait to get a set to start using them. Never stop learning.

[@mrpete222]

👍

[@jamesbarisitz4794]

I make replacement handle scales for folding knives. The blade pivot is usually a counter bored hole. With so many brands out there, it's rare to find a combination of pilot and shaft that match the two holes required. I generally have to make what I need with a drill and a bench grinder! It's easier with a drip bottle over the work piece to keep the temper of the bit while grinding. 😂👍

[@Petzlglyph]

Are the pilots made slightly undersize to fit in standard clearance holes?

[@ellieprice363]

Yes the pilots typically a few thousands smaller than the hole to prevent rubbing and possible seizing.

[@ralphf8951]

Very interesting regarding the spec change from the 30's fastener to the 60's one. I have found this to be true and important to note when servicing older lathes out of the 40's. I pay attention to any changes, by reading a Machinery book from the time period of the lathe vs. a modern one. PS - your program is the best teaching one on the web, always informative and inspirational.

[@mrpete222]

Thank you very very much

[@ruperthartop7202]

Great, thanks for sharing Lyle 👍

[@bc65925]

I sort of drilled a counter bore prior to having any counter bores. When I welded up the stand for my portaband I had a small piece of steel that I drilled to screw into the holes where the guide was. I then drilled two holes in what ended up being the bed with the same spacing but large enough for the heads of the screws. I then welded the small one to the bottom of the bed. Clear as mud?

[@mrpete222]

lol

[@greggroos2271]

Really useful stuff. I bought some new counterbores for 8-32 and 10-32 and they were junk. I had better results grinding my own flat bottom drills. I'll keep an eye out for an older set to try. How are the one piece pilot ones sharpened?

[@PeterWMeek]

When counterboring a hole when only the tap drill hole has been drilled, a smaller pilot is required. This is when the removable pilots would come in handy. I've run into that situation several times and a set of counterbores with changeable pilots would have been very useful.

[@mrpete222]

Thank you, never thought of that

[@whatwillwedonow]

I thought I'd comment since I was first or at least I think I was first to give this a thumbs up. Thanks Mr Pete for all your videos. I have no experience of machine work but have just bought a Colchester Triumph lathe - largely because of your great videos (and those of other talented youtubers) hope you keep well and thanks for everything!!!! Kind regards from the UK

[@mrpete222]

Thank you very much for watching. I hope you enjoy your new machine.

[@gkeyman565]

great video, great info have a great day

[@davidt8438]

I often wonder when watching your videos if while explaining things, you might say for example “I need to clean out the hole and polish up this shank” when you finish the video do you ever go back and clean up and polish or organize some drawer that you mentioned or do you just go about life again and never complete those much needed tasks? And thank you for these wonderful videos. I have learned much over the years.

[@mrpete222]

I am mediately go to bed after I make a video

[@danbreyfogle8486]

I liked the cut away, were you peeking as I got up to go to the bathroom? Very interesting video. And I found the "extra extra credit" interesting as well.

[@chuckyounger7298]

14:47 really enjoyed this one... not “stupid “ at all, thanks ... the little clock marker works haha will make use of that in future comments 14:47

[@Radiotexas]

I learn something every day!

[@jeffmarden9502]

So the size of the counterbore always corresponds with the size of the hole? i.e: for a 1/4 in. drilled hole, you would use a 1/4 in. counterbore?

[@PierreaSweedieCat]

I mever took shop inschool. But boy do I love your videos!

[@mrpete222]

Thank you very much

[@centerfirecentral]

Great information as always. Thanks !

[@BenButler1]

Thanks Lyle!

[@floridaflywheelersantiquee7578]

Thanks for sharing Mr Pete

[@timeflysintheshop]

It is not stupid stuff! If I ever run into the mixed cap screws, I would think I had gone mad. Now I will expect the difference and will maintain my sanity. For at least one more day! 👍😁👍

[@mrpete222]

😄

[@StanErvin-yo9vl]

Comment on @12:01 about the size differences. A small difference exists between bolt grades and also bolt manufacturers. Also, the undercut for the mating surface can vary substantially. Lyle, can you also do a short lesson (or demonstration) of the two different angles in counterboring for flat head machine screws. There is possibly even a third or even more when Whitworth, metric, or jis standards are used. You may need the old reference book and then again, maybe a recent one. 🗜️🔩🪛📐📏🏁 . Shouldn't be too much of a challenge to make a dedicated flycutter with interchangeable cutters and a cute gage to establish angles of both the screws used and the cutter needed for the job at hand. P. S.: When did you last see an elevator bolt?

[@mrpete222]

👍👍

[@MrPossumeyes]

Thanks, Mr Pete!

[@EVILDR235]

Your videos probably boost eBay sellers profits. Excuse me dear, but Mr.Pete just did a video on counter bores and I need to go get some.

[@mrpete222]

You actually cracked me up

[@EVILDR235]

@@mrpete222 I watch a lot of tool related videos and I am guilty of getting on eBay looking for related items.

[@mackdog3270]

Is there any downside to making a jig out of some hex stock and grinding out flats on a straight shanked tool? Besides making me look like a barbarian, that is. Good quality tools are expensive, and I'm hesitant to mess it up.

[@mrpete222]

Give it a try

[@heinstrydom864]

Not borring at all, thank you.

[@howardhilson2374]

I have often counterbored holes using two drills, one with the standard taper and the second with the end ground flat with clearance much like an endmill. It is an easy grind by hand and does a good job. I just run them on the slow side.

[@mrpete222]

I made a video on that two years ago and never did release it

[@100yojimbo]

Another really well explained video, very interesting thanks Mrpete 👍👍👍👍👍

[@mrpete222]

😄😄

[@izzynutz2000]

The gearbox on a Brunswick A2 pinsetter machine is aluminum and all the gear sets that bolt into that use these plus a copper gasket behind them so they don't leak I've had to repair many holes And re drill them and counterbore them I have a set of counterbored drills in my toolbox

[@mrpete222]

👍👍👍👍

[@OleGramps53]

Always educational! If we’re not learning then are we dormant?

[@rodwright225]

Very interesting !!!😎👍👍

[@358trucking]

Awesome video! Makes me want to counterbore something with the set of 7 I just bought off EBay. They seem good quality, I’ll find out! 👍Thanks Again!

[@DunderOz]

Wonderful explanation 👍

[@moms762]

Since you have too many, feel free to send all you want to me.

[@stevenfarrall3942]

I am in the UK and I have got samples of and have used both of those two 5/16th set screws. Mostly from automotive purposes. Ford mainly. I always wondered what was going on.

[@mrpete222]

👍

[@longcaster]

good one

[@user-ce7bj4rk8r]

Great video as always.

[@Duckfarmer27]

Lyle - Good surprise on a Friday morning over coffee. You're not the only one with too many counterbores - and spare pilots that don't fit. Don't ask me how I know.

[@mrpete222]

lol

[@peanutslayer]

At 15:04, what book is that graphic out of that shows the 6 processes?

[@jobos98]

Great Video Mr. Pete

[@duron700r]

I wish I had a good set of counter boring tools. I thought it a neat video and subject!

[@mrpete222]

👍

[@Stefan_Boerjesson]

When boring for threading all is centred. Use a drill bit large enough for the screw head and finish off with an end mill. Much cheaper then buying special tools, not used very often. As You, when You already got them, of course use them.

[@mrpete222]

👍👍

[@mattholden5]

The older version 5/16" bolt head looks very similar to M8x1.25. I wonder if the ASME (or whichever standards body decided to change the diameter) did so to make 5/16" hardware easier to visually differentiate as metric hardware became more common. Interesting history lesson. Thanks Mr Pete.

[@haroldsprenkle4173]

Hey gotta add, depth, i work in die shop. Dies get sharpened, i have seen some really thick shims, and i have had to reduce head thickness of shcs's a time or two. Depth to clear, some is good more is better on die sections.