Drilling end grain

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  • LCHIEN
    Internet Fact Checker
    • Dec 2002
    • 20914
    • Katy, TX, USA.
    • BT3000 vintage 1999

    Drilling end grain

    Here's a problem I always encounter when trying to drill end grain, particularly if trying to put a hole at dead center of a dowel or a board.
    Click image for larger version  Name:	20180821_165447_resized.jpg Views:	1 Size:	37.0 KB ID:	834083
    As you can see the drill bit deflects off the hard edge grain and in this case a 1/8" drill bit is about 1/16th off the location.
    I used a drill press with a 1/8" brad point bit, clamped the workpiece in a vise, I carefully pressed the bit to the marked X and it made a prick right at the intersection before I tried to drill.

    I tried leaving just a half inch of the bit showing from the chuck but it still walked off.
    One thing that sort of works is to drill a template in metal or a crossgrain piece of wood and put two guides on it that can be clamped to the side of the piece being drilled to locate the template hole precisely.

    One thing that just occurred to me is maybe I should try a higher drill RPM?

    How do you guys handle this problem? - I'd really like to drill accurately into endgrain.
    Last edited by LCHIEN; 08-22-2018, 12:29 AM.
    Loring in Katy, TX USA
    If your only tool is a hammer, you tend to treat all problems as if they were nails.
    BT3 FAQ - https://www.sawdustzone.org/forum/di...sked-questions
  • capncarl
    Veteran Member
    • Jan 2007
    • 3564
    • Leesburg Georgia USA
    • SawStop CTS

    #2
    I’ve found that spade bits don’t wander as bad as twist drills.

    Comment

    • leehljp
      Just me
      • Dec 2002
      • 8429
      • Tunica, MS
      • BT3000/3100

      #3
      I have used a nail or punch tapped to about 1/8 inch deep, Knowing that the hard grain is going to push it off, I generally angle the punch into the hard grain from the starting center point on the wood. Apart from that, this is where a brad point bit, higher RPM and slow feed might help.
      Hank Lee

      Experience is what you get when you don't get what you wanted!

      Comment

      • cwsmith
        Veteran Member
        • Dec 2005
        • 2737
        • NY Southern Tier, USA.
        • BT3100-1

        #4
        Looking at the grain of your example piece, I can see that your center mark is right on the hardest grain. Normally, once I get the hole marked, I use a spring-loaded punch to dimple the hole, then use a brad-point drill bit. With that center spike on the bit, set in the dimple, it doesn't wander... but with that exact point your have, I'm not sure that the punch itself might well slide off your point. In which case. using a scrap of the same thickness, I would probably make a 'guide', which I could hold in place and then drill through that. Depends on how hard that wood is.

        CWS
        Think it Through Before You Do!

        Comment

        • Carlos
          Veteran Member
          • Jan 2004
          • 1893
          • Phoenix, AZ, USA.

          #5
          Odd, what you described is what I do, and it's pretty reliable. Brad point bit, sink it to the shoulder before turning on the DP, then drill. I guess the two things I can add are... I start the drilling VERY slowly until the bit takes a bite. And I run it at high speeds, above 2k.

          Maybe try an automatic center punch? I'm not sure why, but in my mind that was always a metalworking tool, and I only recently started using them on wood.

          Comment


          • cwsmith
            cwsmith commented
            Editing a comment
            Carlos,

            I've got a fairly good punch (I call them "spring-loaded", as I see nothing really 'automatic' about them) that I've used for years, bought it for metal but it's a natural for wood. Kept misplacing it, so I bought a couple of similar brass punches from Harbor Freight. Keep one in my electrical bag, one on the drill press, and one in my general tool drawer here in the shop.

            I have multiples of some things, for no other reason than I keep setting them down and can't find them at the moment I need them.... some kind of gremlins I think, so I keep backups. The old ones turn up, but at the moment I need it, I don't want to have to hunt... thus have spares.

            CWS
        • Carlos
          Veteran Member
          • Jan 2004
          • 1893
          • Phoenix, AZ, USA.

          #6
          Yeah, certain tools just deserve to be sitting around everywhere. Tape measures and rulers, pencils and markers, screwdrivers, and sure, a few punches. I too have one in my "go" bag, at the drill press, and a floater that is always in the way when I don't need it and runs away the second I pick up a drill.

          Comment

          • LCHIEN
            Internet Fact Checker
            • Dec 2002
            • 20914
            • Katy, TX, USA.
            • BT3000 vintage 1999

            #7
            I've used the spring loaded "automatic center punch", but it just slides off the grain, too. I'm going to try and use the higher speed.

            P.S (8/25) . I just tried drilling at high speed (2600 RPM) but with a very slow feed, still walked off the grain peak. - no improvement.

            I suspect drilling with a guide or template and a small bit, the hole will force it to enter in the right place but then rapidly skew off to the side as it drills leaving a very non perpendicular hole.
            Last edited by LCHIEN; 08-25-2018, 01:51 AM.
            Loring in Katy, TX USA
            If your only tool is a hammer, you tend to treat all problems as if they were nails.
            BT3 FAQ - https://www.sawdustzone.org/forum/di...sked-questions

            Comment

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