Announcement

Collapse
No announcement yet.

VFD for drill press

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

  • VFD for drill press

    I want to have variable speed on my drill press and in the future on my 12” Atlas lathe. For a VFD setup what kind of motor should I be looking for? I would like to keep 120v input. I considered a DC treadmill motor with PWM but I understand low speed torque would suffer and VFD would be far superior.

  • #2
    I know you can get single phase 120v input 3 phase 230v out drives for 1hp motors. There may be some bigger ones out there but not positive.

    What size drill press and current motor size? Are you also planning on keeping some sort of mechanical speed changes on it?

    Comment


    • #3
      The motor has no hp spec listed, but it is 6amp. The press is a Delta 12" benchtop model Dp350 that has a mechanical variable drive, the one of the drive half pulleys broke and an other has dozens of stress cracks in it, and spare parts are not available. I was only planning single pulleys and would like to have speeds from 350 to 3000prm

      Comment


      • #4
        1 hp 3phase motor with 125/220 3p vfd

        Comment


        • #5
          Originally posted by Butcher View Post
          1 hp 3phase motor with 125/220 3p vfd
          Excellent, exactly what I needed. Does the rated rpm matter?

          Comment


          • #6
            You can use a three phase motor of the same rpm as the existing motor, or slower and use the VFD to run the motor faster than stock for high speed and then have more torque available at lower rpm.
            I bought a six pole three phase motor which runs at about 900rpm and set the VFD to run it at 1.5 times the mains frequency to match the speed of the original single phase motor. The VFD is also programmed to run down to 50% of mains frequency to give a good span for my purposes. I am fortunate to have all 4 pully speeds to make a very large range of usable speeds.
            Three phase motors can be 2, 4, 6 and 8 pole for every rated horsepower.

            This link, although to a UK firm is useful as it gives the power expected from the motors at varying VFD frequencies. You will notice that low frequencies loose a lot of torque, which is important with a drill press as low speeds are usually used for the larger size drills.

            https://inverterdrive.com/group/Motors-AC/
            Last edited by old mart; 08-08-2021, 12:34 PM.

            Comment


            • #7
              Originally posted by Stu View Post
              I was only planning single pulleys and would like to have speeds from 350 to 3000prm
              Personally for that speed range I would think about a 2 speed mechanical belt setup in addition to the vfd.

              If you do a single speed and use a 1800 rpm motor and a drive ratio to get 3000 rpm at 120hz, you’ll be down under 15hz to get to 350rpm.

              Its all doable and would work like that but I think the 2 speed setup would be pretty easy at this point and you would get a little more out of the whole setup.

              Comment


              • #8
                AutomationDirect has the GS series of drives
                with the 120v input and 230v 3ph output option available.
                I have used many of them. All still running years later.
                Some in use 24-7.

                -Doozer
                DZER

                Comment


                • #9
                  Your motor would have only 1/4 of its original power at 15 Hz, ok for tapping small holes but nbg for large drills.

                  Comment


                  • #10
                    I run my lathe and my mill/drill on three-phase 1HP motors using cheap Chinese single- to three-phase inverter VFDs, with excellent results all round.

                    Comment


                    • #11
                      I'll add to the others that you'll still need at least 2, perhaps 3, pulley ratios to get that speed range. I tend to leave my DP in it's middle range and get ~150 to 1500rpm from the treadmill motor. I sometimes use the low range for big drills and tapping, and if I did much woodwork or small drilling projects I'd put it in high range.

                      Comment


                      • #12
                        Isnt 350 rpm way too fast to be useful for drilling in metal?

                        Comment


                        • #13
                          Might be better to get one of those servo type sewing motors. They are closed loop to keep speed under load.

                          Comment


                          • #14
                            Originally posted by plunger View Post
                            Isnt 350 rpm way too fast to be useful for drilling in metal?
                            depends on the drill bit size.

                            Comment


                            • #15
                              Originally posted by lakeside53 View Post

                              depends on the drill bit size.
                              Anything over 12mm

                              Comment

                              Working...
                              X