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split point drill bits

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  • split point drill bits

    Bought some 135 degree split pt bits (mastercraft import brand) and when I try to drill thru 1/8" angle iron (1/4" bit) they go about 1/32 then squeal like crazy and dont want to cut any further. My 30 yr old no name HSS bits still cut thru just fine. Any ideas? Thanks

  • #2
    What RPM? How much force used to push down?

    They might need to be resharpened, Lots of cheaper drill bits do not come properly sharpened from the factory (or random ones in a set won't be)
    Play Brutal Nature, Black Moons free to play highly realistic voxel sandbox game.


    • #3
      approx 1200rpm, used 3x as much force as the old bits. The new bit looked very sharp but I noticed some ragged edges at 10x right after the 1st use


      • #4
        I would kinda suspect the drill bits then. Using too little force can cause them to rub and quickly dull, but too much force usally just snaps them, unless you use lots of force before it starts spinning.

        Do you have any diamond hones or even sharpening stones? Try carefuly aligning it to the angle of the tip of the flutes and give it say 5~10 strokes. Its the grey shaded area you need to sharpen, Idealy without messing up the point in the center too much.

        While a few strokes won't correct any serious error, it should get it cutting again. And if you mess up, Well, you still have 2~4" left to sharpen..
        Play Brutal Nature, Black Moons free to play highly realistic voxel sandbox game.


        • #5
          The real issue for me is that these are brand new bits which look perfectly sharp but they don't cut as well the ones I have been using for years.

          Thanks for the sharpening info though, I will use it on my old bits.


          • #6
            Yea, Just because they are new does not mean they where sharpened correctly. I don't get it but somehow they manage to screw up, sometimes just on a few bits while getting others perfect, other times entire sets.

            Other times they are sharpened 'correctly', but the finish on the sharpened areas looks like it was done with a broad axe.

            Sometimes they are not sharpened all the way to the tip, leaving a blunt, other times the angle is wrong and theres really no relief, Either way they won't cut at all. Its basicly the only thing that will stop a bit from drilling. Not being sharp to the point of being blunt, and/or no relief. (Basicly being blunt is the same as no relief)
            Play Brutal Nature, Black Moons free to play highly realistic voxel sandbox game.


            • #7
              Somewhere this subject has come up before...... several times I believe.
              Cheap Chinese drill bits. Good quality brand name bits are not that much more. What did you save?????? You saved a few pennys and bought a bunch of aggrevation. My brother inlaw but some HF crap drills. The points weren't even on center, as the other poster said they looked like they were sharpened with an ax, these looked that way as well. He couldn't drill alum. with them and one bent at 90 degrees when he was drilling. They weren't even hardened.



              • #8
                Drill Bits

                They are most likely carbon steel, which holds up fine until you actually use them. If your old drills work and these don't, then it's poor quality steel they are made of. Sharpening won't fix that. Stick with the 135 degree split point when you get some good ones.


                • #9
                  I think I found your problem:

                  Originally posted by martik
                  Bought some 135 degree split pt bits (mastercraft import brand)
                  For the benefit of non Canuks, mastercraft is a brand of a local retailer, Canadian tire. the stuff Canadian Tire sells is generally junk, not even self respecting I-put-my-own-shelf-up-guy's even buy it

                  Its not just how sharp it is, its the quality of the steel and the heat treatment process. For example you could put a razor edge on a piece of mild steel but it won't cut either. For putting a plug in drywall you won't notice it, but cutting metal you will. Find out where the industrial supply/machinist tools places near you and you will never darken the doorstep at crappy tire again . If there's nothing local, KBC has a good web order service


                  • #10
                    "No-name" like "mastercraft" are going to be chinese or Indian in general..... Sometimes that isn't true, but anymore it will be 99% of the time. Look for an origin on the packaging.

                    Quality on that type is so variable as to be non-existent.

                    If, in addition to being no-name, they have the typical gold-colored nitride "pixi dust" coating, they are typical chinese drills, often apparently made of mild steel, and they wont work. Just toss them in the scrap for recycling..... if the scrappy will even take them. Chalk it up to experience.

                    The case might be useful to hold "real" drill bits.

                    Old-time "no-name" were made by a quality company, because there weren't many trashy companies in the biz.

                    Keep eye on ball.
                    Hashim Khan


                    • #11
                      Oh yeah1

                      We call 'em "Mastercrap" round these parts. Horrid stuff except for some selected wrenches, ratchets, sockets.


                      • #12
                        Originally posted by chrisfournier
                        We call 'em "Mastercrap" round these parts. Horrid stuff except for some selected wrenches, ratchets, sockets.
                        good point, credit where credit is due, their high end socket/wrench line is pretty nice.


                        • #13
                          Since we are talking about drill bits here...

                          Are the "Made in USA" brand that Enco sell actually Made in the U.S.A., or is that just marketing?


                          • #14
                            Yup, i agree those crappy bits from Crappy tire are very bad. I tried them and most of the angles were way off.
                            As advised spend the extra and buy a good set, if you don,t need a full set right now, buy only a few sizes you need, then buy the rest later.


                            • #15
                              OK, One more question. This was normal mild steel angle iron and not bed frame angle iron right? Because that stuff is shear hell on drill bits. If it's just run of the mill mild steel then your now a far more experienced person in regards to Crappy Tire quality control. It cost me far too many hundreds to finally learn that cheap cutting tools are far more expensive than higher priced, Better quality cutting tools. Cheap cutting tools just aren't worth the agravation IMO.