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  • CNC Lathe Gloat

    Bought a little CNC lathe today. Neat little Hercus Compulathe. 8" swing ~14" between centers. 8 tool turret. Made in '86.



    Really well built. Two people can barely lift it. It is a V way machine but there is a integral stainless chip guard that keep the chips out of where they should not. The carriage and tailstock actually wrap around and under the guard. The 3 jaw chuck is made by Pratt-Bernard.

    Its all servo driven Resolvers on the axis' as well as the spindle.

    Bad thing is the control wont boot up. Just a solid cursor. Now if I can just find a SVGA LCD screen to replace the monitor I can retrofit it. I have a couple 200 watt brushless servos and drives with step/dir inputs made by SimpleServo. Might be a good option for the machine.

    Ill take a better pic when I bring my camera to work tomorrow.

  • #2
    Machtool on the PM forum might know a bit about the workings of it...The control it used was used by a few other Australian manufacturers of CNC gear...I think it is an ANCA 2000 control. They were made primarily for schools and other teaching establishments, but the idea must not have taken off as they no longer make them (they don't make any machine tools any more, but interestingly Hercus made the last South Bends a couple of years ago))

    You need to find a Compumill now and you will complete the set.
    Last edited by .RC.; 04-25-2009, 05:53 AM.
    Precision takes time.

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    • #3
      That's a good find Macona, I have the same machine only it has a quick change toolpost, no turret. I use it mainly for screwcutting and radius turning.

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      • #4
        Too bad the original control is toast.

        Open it up and look it over real good, maybe you'll luck out and find a blown fuse or loose connection.


        I'm going to sit over here and turn "envy green" and fume for awhile now.
        This product has been determined by the state of California to cause permanent irreversible death. This statement may or may not be recognized as valid by all states.
        Heirs of an old war/that's what we've become Inheriting troubles I'm mentally numb
        Plastic Operators Dot Com

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        • #5
          They are still well worth buying.
          OK so the electronics are dated and probably U/S but to be honest that the good part

          The mechanicals of these are usually very good , most have probably never done anything like work either because the teachers had no clue about working them or they broke down and there were no funds for repair.

          Now back to the electronics, most would have expensive and now obsolete custom cards in them. Probably only half stepping at most.
          Other quirks would be a limited number of threads available given course threads require high Z axis feeds.
          Many were only programmable for external threads.

          Now by keeping the original motors and mechanical drives possibly the power supply, then fitting a new breakout board and 2 or 3 new microstepping drivers means you can run off a normal PC with advanced features like conversational programming and far more on screen commands like machine offsets and work offsets.

          I have just finished, on Friday, a router that was built at no mean cost for a college.
          This is the sister machine to the one I have done.



          Two days to gut it and replace all the boards and now it's running happily away on mach3.

          .
          .

          Sir John , Earl of Bligeport & Sudspumpwater. MBE [ Motor Bike Engineer ] Nottingham England.



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          • #6
            No steppers in this machine! It's fully servo driven. It has pm servos on x and z and resolver feedback on all axis' including the spindle. One option is to use gecko servo drives. There is a IC made by analog that takes a resolver signal and creates a 1024 line ABZ encoder output so I might be able to keep much if the existing wiring.

            I did find one company that still supports the anca 2000 control do I will try contacting them Monday. I did find the backup batter is bad. I wonder if that would stop it from booting? It's all ROM based.

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            • #7
              You might be on to something.

              Maybe a parameter bank got dumped and all you have to do is put a new battery in and remind it where zero is.

              Big question is... did you get the documentation?
              This product has been determined by the state of California to cause permanent irreversible death. This statement may or may not be recognized as valid by all states.
              Heirs of an old war/that's what we've become Inheriting troubles I'm mentally numb
              Plastic Operators Dot Com

              Comment


              • #8
                Got the manuals, but... Found the problem. Nice burn spot on the main board. Around one of the analog connections to the servo drive for one of the axis's are some burned up components. Only thing i can think of is something happened in the servo drive and high current got into the main board. The board was even burned on the back side!



                So I have three routes to repair it. The control is toast and even if I did repair I would still have a 23 year old control. First, I can keep the original servos and drive them with something like the Gecko 320 servo drives and and install encoders on them for feedback. This would be the most expensive route. Somewhat time consuming as I need to pull the bed off to run new encoder wires. Also the resolver in the head would have to be replaced.

                Second, I found Analog Devices makes an IC that drives a resolver and outputs position info in serial, parallel, and quadrature with an index pulse at 1024 counts per rev. Accuracy is 11 arc minutes. Plenty good for this. The IC's are around $18 for two. The circuit is real simple to just get the ABZ signals out of it. It is a 44 pin LQFP so I will have to have a board made to do the two axis plus the spindle. Again I would use geckos or an equivalent brush type servo drives.

                Last is I have two 200 watt SimpleServo Ac Brushless Servo motors with brakes and drives. About the same physical size as the original motors. The drives have Step/Dir inputs so I can hook up to any generic parallel port with little issue. Since I have the motors and drives this would be the cheapest but most time consuming as I need to modify brackets and bore the drive pulleys. Also have to pull the bed to run the new wires.

                Tough decision. Leaning towards the second option. I think I can use the original front panel. The opening is 7" for the display so I might be able to find a small LCD to go in its place. Most of the buttons and MPG can be reused I think. May end up going with something like the homann designs ModIO board:

                http://homanndesigns.com/store/index...&products_id=4

                Here are a couple better pics:





                Comment


                • #9
                  Nice find and a very nice looking m/c.By coincidence I have been researching Anca,if,that is indeed what the control is for the last week.I have been looking at buying a Farley cnc plasma m/c and every one I `ve seen has an Anca control.It stands for Australian Numerical Control something.
                  Anca cnc grinders who have a site in the UK and probably the States are the same company and according to them can do spares and service on these controls.Additionally Farley has an agent in the UK and again probably has one in the States who have a stock of secondhand and repaired boards for these controls.
                  Mark.

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                  • #10
                    Originally posted by macona
                    Found the problem. Nice burn spot on the main board. Around one of the analog connections to the servo drive for one of the axis's are some burned up components. Only thing i can think of is something happened in the servo drive and high current got into the main board. The board was even burned on the back side!
                    That's why you really want Opto-Isolated driver outputs.
                    That looks like a back-surge from the servos during a crash. If that's a 4-layer board and the PCB has a dedicated ground plane, then it likely fried a lot of stuff on that board besides the obviously black components.

                    Neat machine! I didn't know Hercus made such a machine. *Makes mental note to add another Ebay search item

                    By the way, did you arrange for Nike and Apple sponsorship of TechShop? Man, you're rocking and rolling Jerry!
                    Last edited by lazlo; 04-26-2009, 01:06 PM.
                    "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                    • #11
                      That connector is the analog control signal section. Tough to put an option isolator on that one!

                      The board is two layer. This was made in 1986. So even if I could repair it I would still not have the parameters for it and be stuck with a 23 year old control that requires me to drip feed the programs from a pc. Not worth it.

                      I think I am just going to do the brushless servos. Don't have any other plans for them an by the time I try the other options I am spending $300 more.

                      I have a friend who does contract work for Nike building mock-ups. They had all these store fixtures made for a test store and when they are done they toss them. Nike gave them to me unstead of tossing them. They are built incredibly well. They weigh a ton. We had one shelf unit about 3' x 6' an about 5' high. Two people can barely lift one side to get a cart under it.

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                      • #12
                        Originally posted by macona
                        That connector is the analog control signal section. Tough to put an option isolator on that one!
                        That's odd -- I don't see any power FET's near the DB9 connector, so I was guessing that was driving an outboard servo amplifier. I can't read the part numbers on the packages, but if the burnt DIP package is an H-bridge driver, those must be tiny little servos?

                        If it's a 2-layer PCB, you might be able to save it: the back-surge will usually pop the ground trace, which prevents the damage from propagating across the board.
                        "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                        • #13
                          Gloat??? Isn't it a rule that for something to be a gloat you have to tell how much you paid for it?

                          It does look like a pretty nice machine, unusually well built for a small one.

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                          • #14
                            Oh, I paid $1200 for it. The iron alone is worth it. Pulled it apart today. The ways are in perfect condition. Two V ways and they are hardened and ground. I cant get over how well its built. Even the chip covers are cast. Very well machined. The saddle glides along the ways with ease.



                            The two ICs are a digital to analog converter and quad op-amp. Also some burned up decoupling caps and ICs. Bus voltage was good so the board should have done something. Its toast. The output here was a positive or negative voltage signal that drove the servo amp. Dont know if it was +/-10v or not but I bet it was. The servo drive board can be seen in the bottom right corner of this pic:



                            The transformer drives all of the power electronics like the spindle control which is in the bottom left corner. There is a switching supply beneath the main board that supplies +/- 15v, 24v, and 5v.

                            Like I mentioned above I started gutting it today. Pulled the servos and resolvers. Found the limits. The screws are not ball screws. They are something called a satellite roller screw made by Rollvis in Switzerland http://www.rollvis.com/EN/index.htm. The Z axis does not feel so hot so I might go ahead and replace it with a ball screw. Tried cleaning but it dosnt look good. The X screw seems OK.

                            The brushless servos I have will fit in the spots where the old motors are. I can direct drive the X screw. Max speed of 472 inches per min that way.

                            The last goofy thing I have found is the spindle .55kw DC spindle motor is rated for 180v, yet the original stock drive runs off of 120v. Might just go ahead and replace the motor too.
                            Last edited by macona; 04-27-2009, 01:03 AM.

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                            • #15
                              Originally posted by macona
                              The two ICs are a digital to analog converter and quad op-amp. Also some burned up decoupling caps and ICs. Bus voltage was good so the board should have done something. Its toast. The output here was a positive or negative voltage signal that drove the servo amp.
                              Ah, that sounds like a differential control signal for an outboard servo amp. That should have been opto-isolated.

                              The screws are not ball screws. They are something called a satellite roller screw
                              A planetary roller screw. I have a couple -- they're really neat: they support really high axial load because of all the contact with the planetary screw followers.

                              There was a thread on CNCZone with guys making home-brew versions, but they didn't seem very sucessfull. Mine have very fine thread pitch (.5 mm), but the actual lead (travel per turn of the planetary nut) is multiplied by the number of planetaries -- 4 on mine.
                              Last edited by lazlo; 04-27-2009, 01:19 AM.
                              "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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