emco pc mill 50 & similar

[RandEE]

Nice pics, thanks for sharing!

So what do you search for to find that rotary axis?
Just day dreaming now, I have been searching on Fleabay for parts.

Thanks for pointing out that power supply. 1 piece of the puzzle done.

[RCREDD]

Rotary table. There are a few good ones on fleabay and alot of bad ones.

below is a link to the table I have. This is their version of what I did. Not sure who sells the complete unit.

TAIWAN HOW-MAU CNC MACHINERY, Mini Milling Machine, Desktop Lathe, -- 4" Motorized Rotary Table

[the-jackal]

Hey, I was just wondering if you were still planning on doing the write up for the retrofit.

[redridertwo]

new here looking for how much a emco pc 50 mill would run with it ready to run how much would a used one go for any help would be great

[redridertwo]

what is a emco pc 50 worth with all the software? thanks for any help

[RCREDD]

Jackal,

I could have sworn I sent you the rough draft of the conversion????? Maybe I sent it to someone else. My business has been keeping me working about 18hrs a day and no time to play. I wrote it up and have the rough draft laying around. I will post it as soon as I find t again and if you have any questions feel fre to PM me. I don't get a chance to browse or lurk here lately.

RCREDD

[RCREDD]

That is a loaded question. To me an Emco PC50/55 is worth the same value with or without the software. Personally I would prefer to buy one without any control software etc. Then Idon't have to think about doing a retro, I just do it.

But to answer your question I paid $2800 for my PC55 with the computer, control panel and software. It no longer runs as originally configured and I would have it any other way.

[RandEE]

what is a emco pc 50 worth with all the software? thanks for any help

I have been trying find the answer to that question as well.

There is this one...
EMCO PC MILL 50 CNC w/Computer, Software & Manual | eBay

with computer and software for $5,800 a little high i would think, but not sure. I am thinking it was retrofitted.

I have seen others selling for $800 and this one..
EMCO PC MILL 50 CNC | eBay

Does the mill in question have a RS485 card? has it been retrofitted?

[RandEE]

Jackal,

I could have sworn I sent you the rough draft of the conversion????? Maybe I sent it to someone else. My business has been keeping me working about 18hrs a day and no time to play. I wrote it up and have the rough draft laying around. I will post it as soon as I find t again and if you have any questions feel fre to PM me. I don't get a chance to browse or lurk here lately.

RCREDD

You sent it to me, with your permission I will post it if you'd like.

[RandEE]

Just posting this for all interested. This is from RCREDD and his conversion so he could use a 4th axis. All thanks go to him for this well laid out and informative explanation of his retrofit.

________________________________________


Converting the Emco PC Mill 55

The only reason I converted my Emco Mill was to add 4th axis capability. The following is what I did to upgrade the machine. You may choose to use other methods and or materials.
The following is a list of items you will need to do the retrofit.

1. A suitable power supply. I used a SOLA 48volt 12amp regulated supply

2. A Breakout Board and Motor Drivers. I used a Gecko G540

3. A VFD (variable frequency drive) to control the spindle. I used a KB KBVF 23D. On my machine I decided I wanted to have a manual control of the spindle speed mounted on the machine cabinet. I mounted a pot on the right side of the machine and wired it to the VFD to control spindle speed.

4. Three stepper motors. The best motors for use in the Emco, (my opinion only) are the Vexta #PK-268-03 Bi-polar 4 wire motors.

5. I also added a homemade flip-flop relay circuit to prevent the spindle from being placed in reverse while running forward and vice-versa.

6. I also added a Tyco 4 pin AMP style connector to the left side of the machine enclosure for my 4th axis along with an insulated audio jack for a digitizing probe. These are optional.

7. I used the original pulleys and belts on the 3 axis drives. You may want or need to replace.
I used an old egg carton to store the screws removed during the conversion.


------------------------------------------



1. If possible, before starting the retrofit, lower the head of the machine and block it to prevent personal injury or damage to the machine when the Z axis motor is removed.

2. Unplug or disable power to the machine. Remove the back panels (there are three) and the top cover over the spindle motor.

3. Unplug all connectors from control boards and carefully remove the three boards. They are held in with four screws each.

4. Remove all wiring, transformer, terminals, fans, wire channels etc. The only wires left should be the 3 axis cables, spindle cable, E-Stop cable, door open cable and the limit/proximity switch cables. Leave these in place for now.

5. While at the back of the machine, remove the Y axis motor mount with motor and switches. Disconnect wires from limit switch, unscrew the proximity switch from the bracket and remove 4 screws from the wire cover of the motor. Then remove the wires from the motor. Set the motor aside for now. You will not need the Proximity switch.

6. BE SURE THE MACHINE HEAD IS BLOCKED and remove the Z axis motor mount. Again remove the proximity switch, wires, etc. as done in step 5.

7. Move to the front of the machine and remove the covers from the X axis motor and remove motor mount, etc. as in step 5.

8. If you do not want to keep the door open switch, now is the time to eliminate it. You can remove the door and remove the switch and wire.

9. On my machine, the 4 stepper motor mount holes did not line up with my new NEMA 23 motors. Place the motors into the mounts and slightly rotate them to expose fresh meat, transfer punch new locations, drill and tap for 10-32 SHCS’s.

10. You now have to make the decision on how fast you want your feeds to be. If you want to be in the 15-20 ipm range, you will need to either, carefully remove the stepper pulleys from the stock motors, ream them to ¼” (if needed) and install them on the new motors, or if wanted, purchase new pulleys from a number of sources and use them.

11. If you want faster feeds, then you will need to remove the pulleys from the lead screws and replace them with smaller pulleys. To remove the pulleys, first remove the 6mm set screw in the center of the pulley. It is very tight and set with thread locker. Use a tapered wooden wedge to hold the pulley from turning. The pulley is threaded 6mm so any replacement pulley will need to also be threaded. You will then either need to modify the large pulleys to fit the steppers or purchase new pulleys.

12. Next is laying out the control cabinet. I removed the rear cabinet from my machine and placed it on a set of saw horses. At this point it should be completely striped with nothing in it.

13. You want to place the components in the cabinet to get an idea of where to mount everything. I placed the power supply on the right side, VFD and Gecko on the left side. The Gecko was mounted into a aluminum panel and mounted on standoffs. I cut the panel opening on one of my other machines. You may want to do this before starting the retrofit if possible.

14. You can either use existing terminal blocks or purchase new terminal strips to do the wiring. I have a good supply of terminal strips on hand and used them.

15. Mount all the components in the cabinet. Make sure you have air circulation and working room around them.

16. The wiring is the easiest part of the whole retrofit. Mount one 12 position terminal strip near the Gecko making sure it is on the same side as the 12 position wiring input on the Gecko.
17. Run wires from the 12 terminals on the Gecko to terminals on one side of the strip. On the other side of the strip Terminal 1=x limit switch, 2=y limit, 3=z limit, 4=digitizing jack (if wanted), 5=CW relay, 6=CCW relay, etc., etc. See Gecko documentation.

18. I also mounted another terminal strip for control ground. This strip ties all of the ground side wires from limit switches, etc. together. This is not a mains ground!!!

19. On the opposite side of the Gecko I mounted another 12 position terminal strip. This strip handles X, Y and Z motor wires on one side and wire DB-9s to the other side that plug into the Gecko. Again this allows you to make changes in your wiring very easy, if needed. Emco wiring cables have the individual wires marked 1,2,3,4 etc. This makes it very easy to keep everything straight.

20. Install the motor wires into the block as X 1,2,3,4; Y 1,2,3,4; Z 1,2,3,4. The DB-9 wiring should be A,/A,B,/B on all three. On the other end of the motor cables I used 4 pin Molex connectors to make it easy on that end.

21. To enable M3/M4 (clockwise/counter clockwise) switching, I used two relays mounted on a Radio Shack PC board and encased with shrink tubing. The relays I had on hand and used are 5vdc, so I installed a 5v wallwart inside the cabinet to power the relay circuit.

22. I used the original key-switch and there are a number of wires coming from the mains connector. Isolate the one you want to use (check with meter between L1 of the EIC connector and wires). Run this wire to the switch, power then runs to Power supply, VFD, cooling fans (be sure to use 120v fans), cabinet light (if used) and auxiliary power outlet(s).

23. Follow wiring diagrams supplied with the VFD for wiring the motor. I also have an external switch on the machine to turn cabinet light on and off.

--------
end

[AWysiecki]

Kevin,

Our school machines are having some troubles to work properly. Both the Emco PC Mill 55 and the PC Turn 55 are no getting signal form the computer. I've checked the dongle board config and it seems to be right. Could be a problem with the onboard network connection? As soon as I start WinNC, both mill and lathe make a very low noise that makes me belive that the machine is having connection with the pc, but when i'm trying to move any of the axis nothing happens. The pc position shows all ot the values at zero, different to machine real position..
I sent you today a private message but i'm not realy sure if this was sent to you.
Help from anyone is appreciated!

Thanks

[yvesdupre]

Hello,

i have also bought an emco pc mill 50 w/o any software or control, It is in a not so good condition and bit rusty but i only paid 1300€ .
I now have to retrofit the machine.
My question is why do all the retrofits install new steppers & drivers.
Can´t the original stepper with driver be connected to a new control. The stepper drive seems to have CLK and DIR inputs as can be seen on the electrical scheme i got from emco directly. PM me with your E-mail if anyone wants to have it. I am not completely sure how the signals must be, each axe has 5 inputs :

only the Z-axe has the extra input E-Achse
If anyone knows how to use the original stepper driver i am happy to get that information. I will soon make some tests and put manually 5V on the Inputs to see what will happen.

Regards

Yves

[RCREDD]

The steppers and drive are 5 Phase, which are considered to be smoother and more accurate than 2 or 4 phase motors. In my opinion they are nice motors but under powered for the machine. I am not an EE so I would be taking a shot in the dark as to whether the drive board could be connected to a break out board and driven by one of the popular control programs. I always say given enough time and money anything is possible but not always practical.

As I have said before, I did the upgrade to add a 4th axis by using a Gecko Drive G540. Since my upgrade I have also added a seperate controller and now have 6 axis capability with a custom fixture I have built.

One suggestion is to join the Yahoo Emco groups. One is for the F1 machines and the other is mainly focused on the lathe's, but there is a ton of information and files there, including the schematics and machine drawings.

Good luck and feel free to PM me regarding any questions.

[samarkh]

Hi,

THE PROBLEM:
Looks like I’ve just joined the ‘I’ve got a EMCO PC Turn/Mill 50/55 but no interface club’ as well! At least I’m in the lucky position of having a heap of manuals for both the PC Turn 50 & PC Mill 50, along with version 3.3 of WinNC.
As I read various pieces from around the internet, it looks like that unless you have an ISA EMCO RS485 interface card mounted in an old PC running Windows 3.11 you are not going to be successful! This is the situation I find myself in.

THE INVESTERGATION
I had a quick look in the back of my Turn 50 and removed the control interface card (Y4A 018 000). If you look at the bottom right of the PCB you will see chip marked D201 (AM26LS32ACN). Its output’s feed the X and Z axis decoder & driver chips. I do not know what the driver chips are as they are covered in a heat sink, and I think if I remove the heat sink I might destroy the chip.

I don’t know if the motors are microstepping or not can someone advise please?

I haven’t had chance to inject a signal in to the output of D201 yet to see what happens. I will let you know as soon as I have a chance to pull D201 and play around.


THE SOLUTION
??

Yours Simon M
PS I hope this image shows where I intend to inject signals


PPS Zero CNC knowledge, BUT a fully qualified tinkerer and Electronics Engineer to boot!

[RCREDD]

Welcome to the club.

I am currently converting a PC55 Turn and am doing a total write-up with pictures and supporting documents for publication after I'm done.

I have now done a number of these conversions and have found that there are different control configurations within models.

This current PC55 Turn has 3 phase steppers instead of 5 phase. It also has a seperate VFD for the spindle (very Nice!).

After stripping the whole unit down, I am rebuilding it with an internal PC motherboard and PS. This machine also will be equiped with a 15" touch screen monitor.

I am driving new nema 23 270inch steppers with a geckodrive G540. Power is supplied by the original Emco power supply.

The tool turret will be driven by a nema 17 stepper with a single homing switch.

It would be nice if someone out there was able to sneak past the original computer card. May that someone will be you. Good luck.

[samarkh]

Hi RCREDD,
I look forward to seeing your work.
Because I'm flat broke, I can't see that I'll be able to do much in the way of stepper swapping, but the electronics, that will be cheaper option for me. My biggest problem I think will be getting a CAM package to talk to the EMCO's on a more modern interface eg USB/ Ethernet,
Have you seen this by the way?

14.6 TUTORIAL - PC TURN 50 LATHE DOCUMENTATION: (By Jonathan DeBoer)

Yours Simon M.

[RCREDD]

On my personal machine, which is a pc mill 50, I originally ran the win cnc software. Then I switched over to Mach3 and never looked back.

I already had a seat of mastercam x3 (I have MC going all the way back to 5.5 on floppy disk). I think mach 3 will read dxf files and then there is lazy cam also.

[samarkh]

OK with regards to the EMCO PC Turn / Mill 50:

1) They use 5 phase steppers, and these are 500 steps per revolution.
(Does anyone know if they are micro stepped?)
2) There is no feed back to the PC as to the position of the motor(s), other than the limit switches.
3) The RS485 is a proprietary signal that is unique to EMCO

Please correct me before I start on a design..

Yours Simon M.

[UUU]

On my PCmill 50 there were rotation sensors on the ends of the axis leadscrews. These would have provided a once-a-revolution feedback to the control system. So perhaps not capable of detecting a few lost steps but would detect a baulked movement.

[samarkh]

Thanks UUU,
That is the sort of info I need!
I'll have a look at the end of these screws.


Yours Simon M.