How to drill through the centre of a bolt | drill bolt guide

How to drill through the centre of a bolt | drill bolt guide

in a previous video I used some cap head or socket head bolts like that with a hole drilled down the center to remove some broken bolts obviously if you’ve got access to a lathe with a three jaw Chuck drilling something like that is incredibly easy I can simply put it in the lathe and drill straight through it with minimal setup however most people do not have access to a lathe so in this video we’re going to drill directly down the center of a bolt like that using a pillar drill. To set up the pillar drill you will need either a piece of threaded bar or a bolt the same diameter as the bolt that you want to drill through. Here I am cutting the head off this M12 bolt before we drill this in the pillar drill I’ll just show you the easy way on the lathe simply put the bolt in the chuck ensuring that you grip it with the head insert an m6 drill bit into the chuck normally would use the coolant feed but in this example I’m going to use metal working spray if you’re not familiar with drilling on the lathe you need to peck at the bolt so you go forwards then back it off then go forwards again and repeat this until you are through the other side if you try and go through in one movement there is a chance that the hole will not be dead central as the drill bit can wonder, or so I have been told this is the bolt with the hole drilled dead down the center now it’s time for the pillar drill. start off by putting a piece of threaded bar in the chuck with the nut screwed on to the end adjust the table so that the nut can be gripped in the drill vise now lower the drill so that the nut sits in the jaws of the Vice position the nut so that the vice will not move the nut when the jaws are fully tightened you need to get the vice in a position where you can bolt it down to the table of the pillar drill you can now carefully rotate the vice until the bolt holes line up in the table and bolt it down ensure the bolt or bolts are really tight you don’t want the vice to move now undo the chuck and unscrew the threaded bar get the bolt that you want to drill through in this case a M12 socket or cap head bolt and the thread a nut onto it. then thread the bolt into the nut in the vice screw the bolt all the way down then tighten the top nut using a spanner. this will ensure that the bolt is held tightly you can now get the drill bit in this case a six millimeter diameter one and fit that into the chuck by doing it this way you can be certain that the drill is in the dead center of the bolt you can now proceed to drill the hole ensure a cutting compound or coolant is used to prevent the drill bit from over heating in less than two minutes you should be through the bolt and now have a useful drill guide for broken bolts I hope you found this video useful if you have and you haven’t done so already please subscribe to the channel

About the Author: Michael Flood


  1. Great tip, well edited and good sound/voice over. Who would leave a thumbs down? I thought this was great! Thank you for posting this video.

  2. Very clever, and it also works on ordinary hex bolts not just Allen key bolts. But actually one should have a lathe. What is a shop without it? (Wished I had one)

  3. Very nice solution to a rea l problem. I usually take a drill Chuck that I mounted to a flat plate and set it on the drill press table. Then I chuck a rod in the drill press and the other end in the chuck on the table. Then I clamp the lower chuck to the table. Now I chuck my bolt in the drill press and my bit in the lower chuck and drill away. The chips fall out of the hole nicely and I can drill different sizes without changing my setup.

  4. Absolutely brilliant, never thought of this! Saw your video this morning and literally used it at work today! (power station annual shutdown)

  5. In all seriousness though, would you consider making a set to sell? I don't have access to a lathe or pillar drill. Great idea, so much so that I shared the extraction video to all my friends.

  6. Thank you, you have shown a very handy technique of centering without fancy tools. This would come in handy for a home DIY or small shop.

  7. Good video!
    About 30 years in industrial maintenance here, and I really like all the suggestions for doing something so seemingly simple.
    "There's more than one way to skin a cat" comes to mind, and I have had to do this several times over the years, and it seems I've had to do it several different ways because of circumstances and the resources available.

    One thing I would like to point out, though, especially to folks on the Western side of the Atlantic, is that by and large, the most common SHCS (socket head cap screw) over here is usually found in the 'black oxide' variety, and the vast majority of them are hard as hell – pretty much equivalent to Grade 10.
    The reason I bring this up is because a normal HSS drill will usually have a hella time drilling through a bolt like that, so I suggest using at least a Cobalt bit, or (if you're stacked with cash) a carbide bit.
    Even a TiN or TAlN drill would be better than a HSS, but still you're gonna stand a good chance of burning it up if you're not careful.

    One thing you CAN do, however, is just get a skank Grade 3 or lower hex head bolt, grind the markings flat off the top, and drill it. You can even do that with a "bright" drill with little problem.

  8. I wonder if today's "new" mechanics know about any of these tricks. All they seem to do now is look at a computer screen and change out parts. My Brother in Law is a Toyota mechanic : he didn't even know what a set of contact points and condenser was in an auto ignition system! Of course, Toyota is a disposable vehicle anyway, don't fix, replace!

  9. hi brilliant video as always what size do you use for each size you made like m6 to m12 what drill bit size do you use for each one thanks

  10. Strange logic. "Most people don't have access to a lathe so use a pillar drill instead" (that most people do have access to)? I would have said that if you don't have access to a lathe you are unlikely to have assess to a pillar drill instead. Not criticizing the video itself as it showed a good method of lining up the bolt to drill a straight hole using a pillar drill. Would have been useful to have ideas about how to drill through a bolt using hand held tools and available materials as this is the situation you would have on site.

  11. I`m a retired machinist but feel like a noobe after watching some of these vids. I just wish he didn`t have such a heavy English accent…lol.

  12. Now this is a great tip! I simply love it. Iโ€™ll pass this one around to my friends for sure. For accuracy this is the best way. Iโ€™ve tried it other ways like the comments that are posted here by others but your way is to the most accurate way. You should make these and sell them. Are they already on the market by someone?

  13. Great video and excellent tips! I hadn't known of this method of alignment on a drill press before stumbling across this video a few months ago.

    I have used it to make several slide hammer adapters and snowmachine clutch pullers for shop use. Even made a video on crafting a snowmachine clutch puller.

    I appreciate tips like this that don't have any extra equipment cost, but there is so much to gain. (Assuming one has a drill press and vice.)


  14. A good precise way of hold the bolt exactly in the center by using the thread bar to align it correctly. Great work.

  15. Thanks. I will definitely use this. Not sure what is up with all the "Thumb down" people. They are on all channels these days. I wonder if its not part of the attack by YT in their greed. If they have a better way, then show us. But this is as good a way I've ever seen. Thanks for sharing.

  16. Great idea, I am fortunate and have a small lathe to make this process a bit easier. You have all the right tools!

  17. Excellent video. Brilliantly detailed ๐Ÿ‘๐Ÿ‘๐Ÿ‘๐Ÿฅณ๐Ÿฅณ๐Ÿ‘๐Ÿ‘๐Ÿ‘ Thank you so very much

  18. A strong tip about drilling in center line and straight: Spin the work and hold the drill bit. It's self-centering like spinning a basketball on your finger will self align on your fingertip.

    So if i had bare tools and no drill-press or lathe, I'd chuck the drill in a bench-vice and spin the bolt a hand-drill and in the initial step feel when it's centered as the wobble goes away.

    BTW, the lathe does the same thing.. spins the work.
    Spinning the work will ensure a hole true to the rotation axis of the work. While spinning the drill will get a hole true to the rotation axis of the bit which is in no way dependent to the work so great care must be taken like in this video to setup the axis of the bit to the work. The other way around is much more easy and non-dependent to careful alignment of the parts before drilling. You will feel that if the bolt will try to spin offcenter to the drill point it will wobble the whole drill and work or likely just slip and bend/break the drill bit

    Also by spinning the piece you can drill a straight hole with a bent drill bit. not best combo but is possible much more than the other way around as the drill will just skip and skate around by the offcenter rotation of the bent drillbit.

  19. I wish I had known of this technique when I was working ….I was a heavy equipment mechanic for ~ 40 years, and never saw anyone use these drill guides for extracting broken bolts….(Facepalm)….

  20. Very Nice Video! Clear and concise. You don't need to buy a lathe or drill press. Take some various size bolts to your local metal working shop and tell them what you want or check with friends.

  21. Nice job using your head. But you should center drill any drilling of holes in a pillar drill press. That way you will have not drill walking going on. Peace too from the other side of the pond.

  22. I bleve it's good way to hole in centre nice thanks for sharing with us ๐Ÿ˜Š๐Ÿ‘๐Ÿ‘๐Ÿ’–๐Ÿ‘Œ๐Ÿ‘๐Ÿ‘

  23. If the chuck is large enough, I just put the bolt in the chuck and put the drill bit in the vise, and drill it like a vertical lathe.

  24. Well, you started off using a lathe, if I have a lathe, I don't need the jig. Easiest way to do this is use a bit the size of the ID of the nut to center it in the vise, the install the bolt and switch to the size drill you want for the hole. Cuts out 70% of the time and the LATHE

  25. Chuck enclosure on the lathe is a great idea! Weโ€™ve probably all done it- once. Nice simple solution fo centering there with the threaded rod and nut.

  26. Normally, I wouldn't touch anything called "Ultimate", but your well paced narration, excellent skill, not to mention Scottish burr, sold me on a subscription!

  27. I did something similar on my mill for a guy. He had a couple of reloading plates that he wanted 3 stations drilled and tapped bigger to load 50 cal. I centered the spindle in between a table slot and screw a tap into the threads all ready their and then put it in the collet chuck and bolted it to the table. I could then drill and tap it with perfect alignment. Good video! ๐Ÿ‘

  28. After hacksawing then drilling with the lathe, you ought to face the hacksawed end of the bolt to insure that the twist bit wonโ€™t be forced off-center by an irregular surface.

  29. Good video. I have seen using a piece of wood too. Drill a smaller than bolt diameter hole with wood secured to table. Then screw in bolt and sell through. Thanks for a more secure approach

  30. good video but to all the replies be honest how many times have you needed to drill a hole through a bolt length wise.

  31. I was doing this when I was eight in my dad's machine shop.
    Now if you sharpen it to a point, you then use the bolts to wedge under someone's tires that keep blocking your drive way.

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