Announcement

Collapse
No announcement yet.

Building Press, lots of holes to drill

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Building Press, lots of holes to drill

    I just got a new Acer milling machine and have it pretty well equipped now. I am in the process of building a 50 ton press. I will be using 6" X 1" hot rolled flats for the uprights, 2 on each side. I will be drilling about 40-1 1/16 inch diameter holes in the flat iron for the table to adjust up and down on. I will be using 4-1" pins holding the table in place into the 6" flat iron so I will have 1/16 play in the holes. Now to the point. I was going to use a drill bit but don't want to cause any undue stress on my machine so I am thinking I will start out drilling 1/4 inch holes with a drill bit, then switching to a 3/4 center cutting end mill in a collet, then switch over to a 1 1/16" center cutting 6 flute end mill to drill to the final size. I will be using the DRO so hole placement should be very accurate. Does this sound like an acceptable method and better than just using a 1 1/16 drill bit? thanks Paul

  • #2
    Get an annular cutter, you won't be sorry.

    Comment


    • #3
      Originally posted by true temper View Post
      Get an annular cutter, you won't be sorry.
      Yes

      Comment


      • #4
        Congrats on the Acer mill! That's a very nice machine.

        End mills make crappy drills. Just get a 1-1/16 annular cutter to start with. That will sink right through and be done in one shot per hole. The next best thing would be start with a 1/4" drill, go to a 1" drill, then a 1-1/16 reamer. Or you could use a 1" annular cutter, then a 1-1/16 end mill or reamer.

        Comment


        • #5
          whats an annular cutter and what do cost True Temper? what is the advantage to what I was going to do? thanks Paul

          Comment


          • #6
            Ok thanks, I will have to price it out. That would be great if it will cut the hole in one pass and hopefully be able to cut all 40 holes in the 1" thick material without wearing out. What kind of spindle speed should it be run at? Paul

            Comment


            • #7
              Cuts round holes like butter, I smile every time I use one. One example, http://www.ebay.com/itm/1-1-16-X-1-l...item417da71791

              Comment


              • #8
                https://www.google.com.au/?gws_rd=ssl#q=broach+cutter

                http://www.machineryhouse.com.au/D9512
                Last edited by oldtiffie; 03-06-2015, 11:13 PM.

                Comment


                • #9
                  will a normal 3/4 collet hold the annular cutter or do I need a special holding tool for it? I have looked in Enco and MSC but they show no tool that they fit into. They are recommended for magnetic drills

                  Comment


                  • #10
                    A Champion CT-7 carbide cutter works real well to cut large holes. I have one I have over 100 holes done with it.
                    Dan.

                    Comment


                    • #11
                      Ok I just ordered the Bison 1-1/16 annular cutter off ebay it was only 25 dollars so I hope I can get through all 40 holes with it. Im doubting it however. and hopefully the 3/4 collet will hold it unless there is a better method. earlier today I ordered the 1- 1/16 center cutting end mill because I thought that was the better method than a regular drill bit.
                      Last edited by pb57; 03-06-2015, 11:59 PM.

                      Comment


                      • #12
                        This would be the best option, http://www.ebay.com/itm/Magnetic-Dri...-/400772073534 I have used a collet and got by fine. A Weldon end mill holder will not work on annular cutters bigger than 3/4" they are too long. Set screw won't reach. I am going to turn one down so it will work.

                        Comment


                        • #13
                          Pb57
                          I have made these remarks on this forum enough for this disclaimer; I don't own or work for any of the annular makers. But they should pay me for the PR.
                          Yep, they are great for making holes, especially large, close to size, repeatable holes that are round, ESPECIALLY on low horsepower machinery.
                          The 3/4 R-8 collet will work but you need to observe a couple things. Since it doesn't have the posi drive screws, don't use power feed. If you spin the collet, its days are over if you can't stop on a dime and let things cool before retracting.
                          Since the collet doesn't have the ejector/locator pin along with interior coolant flow, you get differential expansion, which at worst, causes the above seizing, or just makes it a PITA to remove the slug. Remember to set the start depth at least slug length above the work.
                          Put a gob of Crisco in the cutter bore before you plunge. Use a spray bottle at least.
                          Annulars make nasty uncontrollable birds nests. To avoid that, drill a hole a little less than cutter thickness anywhere in the cutting circle. Also makes slug extraction easy.
                          HSS SFM of 120 or close works for RPM. 40 holes is a cakewalk.

                          Comment


                          • #14
                            The cutters cat be sometimes had cheap on ebay if searched for a bit laterally.

                            In the UK , the technology was pioneered by the RotaBroach company in Sheffield so search Rota Broach , Rotabroach

                            In the US (and UK) , Jancy Engineering sold well with their "Slugger" trademark , So search jancy cutters , slugger cutters , Fein Cutters.

                            Rob

                            Comment


                            • #15
                              As the hole positions by the nature of their intended purpose are not really required to be too accurately placed, and if it were me, I'd mark them out and centre punch the hole centres, use a pilot drill to suit the annular cutter and then either hire of buy a good magnetic-based drill for both the pilot and the cutter - and with a good feed of coolant/lubricant.

                              Do not use a vertical mill as it may cause excessive wear on the mill quill.

                              A good pedestal drill is the way to go if a magnetic-based drill is not available.

                              Comment

                              Working...
                              X