Announcement

Collapse
No announcement yet.

Hollow Mills??

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

  • Hollow Mills??

    Hello,

    Does anybody know where I could get a hollow mill without it being a special order? I need a hollow mill that has a 3/8" center hole.

    Thanks,

    Brian


    Update: Never mind....I just checked e-bay. While I didn't remember seeing them on e-bay, I really never looked specifically for them.
    Last edited by Rif; 03-30-2011, 12:07 AM.
    There are only 10 types of people in the world: Those who understand binary and those who don't.

  • #2
    Wish I knew what a hollow mill might be. Are you referring to an annual cutter? Got a photo, illustration of link to what one looks like? I'm curious.

    Comment


    • #3
      PixMan,
      Old, old, old type: http://www.brown-sharpe.com/102103.php
      Typical HSS type: http://www.jtsmach.com/jtswebshop/MillingTools/M033.asp
      New indexable type: http://www.sommatool.com/catalog/cut...hollowmill.asp

      They're for turret lathe work. Rapid removal of stock.
      Last edited by Arthur.Marks; 03-30-2011, 12:31 AM.

      Comment


      • #4
        I see now that the name is a misnomer as it's not really a milling tool but a turning tool. Not the kind of thing the average home shop machinist needs then is it?

        Comment


        • #5
          Hollow mill

          They are often used to machine a boss or stud on a casting in a mill. It creates an exact size pin with a perpendicular base around it as quick and easy as drilling a hole.
          Kansas City area

          Comment


          • #6
            Given Toolguy's use, are some of them able to be used in a rotating spindle (i.e. mill)? Or do they fly apart

            Comment


            • #7
              Originally posted by Toolguy
              They are often used to machine a boss or stud on a casting in a mill. It creates an exact size pin with a perpendicular base around it as quick and easy as drilling a hole.

              That is what I was looking into. I may have a job that will require that I make many off-center turnings of a 5/8" square brass rod. So, life will be good if I can use my milling machine to machine a boss on the end of the brass. Later I can use the boss to hold the whole thing in a 5c collet on my turret lathe.

              I'll also need to use the hollow mill, on the turret lathe, to machine the other end of the brass bar. After those operations, I should have a 3/8" round bar with a big off-center square section in the middle.

              Regards,

              Brian
              There are only 10 types of people in the world: Those who understand binary and those who don't.

              Comment


              • #8
                So did you end up with a Kutmore off of eBay? Thanks for widening my perspective on the use of these in the mill.

                Comment


                • #9
                  Originally posted by Arthur.Marks
                  So did you end up with a Kutmore off of eBay? Thanks for widening my perspective on the use of these in the mill.
                  Yes, I bought that set of Kutmore adjustable hollow mills.

                  I hope they do what I need.

                  Regards,

                  Brian
                  There are only 10 types of people in the world: Those who understand binary and those who don't.

                  Comment


                  • #10
                    Hollow mill

                    Rif-
                    Why not use a 5/8 square collet with a stop and a vertical collet fixture in the mill? You could cut your bars to finish length to begin with, then simply do each end in the mill with a stop for the quill to come down against. That would go very quickly, especially with an air collet fixture. The cutting edges are held very securely and the hollow mill does not fly apart when rotating.
                    Kansas City area

                    Comment


                    • #11
                      Originally posted by Toolguy
                      Rif-
                      Why not use a 5/8 square collet with a stop and a vertical collet fixture in the mill? You could cut your bars to finish length to begin with, then simply do each end in the mill with a stop for the quill to come down against. That would go very quickly, especially with an air collet fixture. The cutting edges are held very securely and the hollow mill does not fly apart when rotating.

                      That would work nicely. There is only one problem. (Which I didn't mention and you wouldn't have known.) My biggest mill is a Hardinge TM horizontal. (My other mill is a Sherline 2000....let's not go there. )

                      Some day I would really like to get a mill, with a quill.

                      On the other hand, I do have two collet fixtures and would just have to get a square 5/8" 5c collet. (No air collet fixture; but, that would be cool.)

                      I'll certainly keep the 5c collet idea in mind. I was thinking about using a vice and a vice stop.

                      Best Regards,

                      Brian


                      I
                      There are only 10 types of people in the world: Those who understand binary and those who don't.

                      Comment


                      • #12
                        Rotabroach comes to mind

                        http://www.hougen.com/cutters/rotabroach_advantage.html
                        Green Bay, WI

                        Comment


                        • #13
                          Originally posted by Toolguy
                          Rif-
                          Why not use a 5/8 square collet with a stop and a vertical collet fixture in the mill? You could cut your bars to finish length to begin with, then simply do each end in the mill with a stop for the quill to come down against. That would go very quickly, especially with an air collet fixture. The cutting edges are held very securely and the hollow mill does not fly apart when rotating.
                          Hello,

                          I just wanted to add an update and thank you for this advice.

                          I was using a vise and, due to the small size of the brass at only about 1.125 long, I was scrapping a few pieces here and there as they wouldn't always stay in the vise properly. This was even after I tightened it up really tight.

                          So, I remembered your advice and tried it. Using a 5c collet fixture, with a 5/8" square collet, worked great. There was no more scrap. Even the hand cranking on the horizontal mill wasn't bad at all.

                          Here is a link to what I have been making: http://www.reprap.org/wiki/J_Head_Nozzle

                          Thanks!

                          Brian
                          There are only 10 types of people in the world: Those who understand binary and those who don't.

                          Comment


                          • #14
                            Originally posted by Arthur.Marks
                            PixMan,
                            Old, old, old type: http://www.brown-sharpe.com/102103.php
                            Typical HSS type: http://www.jtsmach.com/jtswebshop/MillingTools/M033.asp
                            New indexable type: http://www.sommatool.com/catalog/cut...hollowmill.asp

                            They're for turret lathe work. Rapid removal of stock.

                            Hollow mills ???
                            We know them as tangential box tools.

                            A hollow mill is like a Rota-broach.

                            But a broach is a shaped hardened rod, pushed through a hole to make a shaped hole / keyway/ splines / internal gears .......

                            Then we have
                            Taps you can't hit or get water from, Right hand tools cutting on left & Left hand tools cutting on right,
                            No wonder no one knows what we're talking about (including us )

                            john
                            John

                            I used to be indecisive. Now I'm not so sure , but I'm not a complete idiot - some bits are still missing

                            Comment


                            • #15
                              I'm not really sure I understand what you're trying to do but you might consider grinding a broken or dull end mill to the shape of a lathe parting tool making sure to have a square bottom and then using the boring head and offsetting it such that the inside sweep of the tool generates the diameter of the boss. The process is called "trepanning".

                              EDIT: Check this out http://www.youtube.com/watch?v=Rvk8RKFVXwA

                              You'd be doing this in the mill of course with only one cutting edge if you use the single point tool method described in my post.
                              Last edited by DATo; 05-28-2011, 08:39 PM.

                              Comment

                              Working...
                              X