Announcement

Collapse
No announcement yet.

Why so Expensive to repair Enco Mill?

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

  • Why so Expensive to repair Enco Mill?

    I may have an opportunity to pick up for free an Enco mill from my work. But there's a story that goes with it, so I don't know if I want it or not.

    Some engineer got himself hurt doing whatever nutty thing he was attempting a few weeks ago. The bosses (we think to cover up the truth) had the entire head removed and sent to a repair facility. Mind you, this machine is in pretty dang good shape to LOOK at. Table's tight, shows little wear in the dovetails, they even haven't gouged or drilled the table top! Now the bad part...

    This "repair" shop came back with a quote for almost four grand to "fix" the head (heaven knows what they are going to "fix"). Company wrote them a purchase order, and then, just a couple of days ago, they came back and stated over nine grand to "fix" it. Our company has told them to box the head up and send it back, which means it'll be in pieces when we get it.

    So I have two questions: First, what in hell is so important in that head that's worth nine grand? It's a general question because I can't find a model number until the head comes back. I assume the nameplate is on that part of the machine. If it's going to bankrupt me, I'm not interested. But again, it may just be a reassembly.

    Two, the machine is now 480 volts 3 phase. I am a power electrician, but know little about the machines themselves. Can a VFD be fit to it to run this thing from 240 single phase? Should it be converted to single phase?

    Depending on your general advice, and when the power head comes back, I'll get some pics together and try to have some more details. Then I'll figure out if I want to tackle it.

    Thanks,
    Mark

  • #2
    Mark,

    Find out the name of the repair shop, call them and see if they will let you talk to the person that evaluated the damage to the head. That person would be able to tell you what they found. Don't question the repair quote otherwise they may not tell you anything. Also, try to find out what exactly the engineer did to the machine, i.e. what kind of operation was being performed.

    Chances are very good that it's a dual voltage motor 240/480, so yes, a properly sized single phase to 3 phase VFD will run the mill. I wouldn't convert it to single phase because dealing with low hp 3 phase motors is too cheap and easy these days.

    Comment


    • #3
      Hi,

      A hard to source spindle and bearings can cost a lot if you have someone else do the work. I would second the recommendation on finding out what happened to break it.
      If you think you understand what is going on, you haven't been paying attention.

      Comment


      • #4
        Is it a ram turret type..aka Bridgeport type.
        Whole new head is less than that estimate. .

        Comment


        • #5
          It depends on what got damaged, and how much time they were going to put into it. Keeping in mind their repair shop rate might easily be in the $100+ per hour range.

          For example, when I rebuilt the head on my Exacto, I had to fabricate a new shaft for the backgear engagement (which probably took me 4-5 hours all told) I had to replace the gears that rotate/tram the head (grand total of $700-ish to have those made) replace the spindle bearings ($220 off eBay) straighten and regrind the spindle (another 4-5 hours all told) and about two dozen other little bits. The total rebuild likely took me 30+ hours, doing a little here and a little there.

          If the Enco is a variable speed head, I could see that taking just that much more thanks the the more complex mechanism, and if it's an older unit, it might very well be that certain replacement parts are no longer available, and they're tacking on having to machine pieces from scratch. At $100+ an hour.

          Now, an option is of course to simply get a new head. Last time I looked- in case this Exacto head wasn't salvageable- there were a dozen knee mill heads available just on eBay. Looking up "mill head" under "business and industrial", on the first page there's currently a 1HP single phase Bridgeport step-pulley head, a 2HP variable with a 30 taper spindle, a brand-new "Ganesh" 3Hp variable and a Chevalier 5HP 40-taper variable, all under $2,700.

          Doc.
          Doc's Machine. (Probably not what you expect.)

          Comment


          • #6
            $9K? That is silly. Purchase a new head.

            Comment


            • #7
              Doc's probably onto it....

              Bent spindle, bad bearings, no parts, so spindle etc has to be re-made at shop rates, new bearings, class whatever expensive...... makes you start to understand the $5000 gears from the machine tool parts folks.
              1601

              Keep eye on ball.
              Hashim Khan

              Comment


              • #8
                9K?

                Buy a new mill!

                Comment


                • #9
                  If it is free I would take it how it is and ask questions later before someone else jumps on it or the company changes their minds.
                  Andy

                  Comment


                  • #10
                    My guess is the shop was told to repair it to quality machine tool standards. That could easily be very costly.

                    Years ago I watched the complete rebuilding of a 50 taper Cincinnati horizontal mill in a local machine tool dealer's shop. The process went on for at least a year. I dealt with the dealer frequently so I got in the habit of talking with guy doing the rebuild when I stopped by. When the project got to the point of final scraping I asked what the guy figured costs were to date, he said around $50K. I couldn't resist asking who would spend that kind of money on a manual machine. His answer was "you". Turned out the machine was from a government shop and had been sent in with a PO to be returned to new condition and accuracy. And this was twenty some years ago.

                    Comment


                    • #11
                      I'm with Andy - it's rare that you see "mill" and "free" in the same sentence. Grab it, even if it's in pieces. Then see what's wrong. Plenty of solutions to the 3 phase problem, I'd have thought.

                      Ian
                      All of the gear, no idea...

                      Comment


                      • #12
                        Originally posted by DR View Post
                        Turned out the machine was from a government shop and had been sent in with a PO to be returned to new condition and accuracy.
                        Those programs can be great. My 1951 10ee was refurb'd by the Navy in 1993. They did a bunch of them in the same program, though I don't know how many or the cost. At least 15. Fortunately it received an honorable discharge and was not rusting in a field for a year or more.

                        As for the mill, a head retrofit is easy.

                        Last edited by Glug; 09-01-2017, 10:00 AM.

                        Comment


                        • #13
                          Originally posted by vpt View Post
                          If it is free I would take it how it is and ask questions later before someone else jumps on it or the company changes their minds.
                          Well, Andy probably has the best advice going.

                          I (we) still think that the head was removed to cover up some sort of stupidity by the operator. I'll bet a quarter that there is literally nothing wrong with this machine. It was rarely used, and I doubt if any of those boobs up front even know how to properly fixture a simple job. I'd speculate that the work came off the table and bit the guy. It's being kind of hush hush, but it's been the cause of a lost time injury, so it absolutely had to be a faulty machine.

                          I'm supposedly first (and maybe only) on the list for salvage, so stand by. I'll need lots of help if I do get it... and it can economically be made to throw chips.

                          Thanks folks for some good advice.
                          Mark

                          Comment


                          • #14
                            Grab it for everything else! Fix or replace the head yourself

                            Comment


                            • #15
                              Even if the head is totally crap there is a lot of valuable raw material and finished parts in that machine.
                              *** I always wanted a welding stinger that looked like the north end of a south bound chicken. Often my welds look like somebody pointed the wrong end of a chicken at the joint and squeezed until something came out. Might as well look the part.

                              Comment

                              Working...
                              X