Something different - CNC milling machine build

[freeskier7791]

Dvous thanks for expanding on the topic.  Is that a picture of your machine?

[gc3]

that's the best "what to look for" list ive read yet!
thanks for compiling!

[frijolee]

Bad ass writeup.  Exactly what I was looking for.  Thank you so much.   

[Dvous]

Dvous thanks for expanding on the topic.  Is that a picture of your machine?

No sir, I wish mine was THAT fresh.  Mines in good shape but that's a brand new scrape job.

Bad ass writeup.  Exactly what I was looking for.  Thank you so much.   

My pleasure, like I said before, don't hesitate to contact me with more questions either here or via PM.

[PapioGXL]

Looks like fun. I've been in the market for a knee mill to complement my Harrison 13x40 lathe.

[Dvous]

Okay time to catch up on this a little more.

Once I had the rotary encoders setup on the X and Y motors I ripped into the Z motor.  The Z motor already had a rotary encoder fortunately so it went pretty easy for me (no 3d printed adapter).

Original encoder:
[attachimg=1]

And the mount for the new encoder screwed in:
[attachimg=2]

I don't have it pictured but I did everything else the same as the other two motors as far as the line driver card and the ethernet bulkhead in the cover.

[Dvous]

btw, sorry for all the cell phone pics.  I'm too lazy to use a real camera  .

Anyway, once the motors/encoders were sorted I decided it was time to rip into the old control box.

Old controls:
[attachimg=1]

What you see in that pic are 3 Glentek servo drivers to match the glentek motors.  The power supply is simply rectified 110VAC to make 155VDC with a big cap. and separate fuses for each axis...very simple.  I'll be retaining the old power supply setup for testing purposes but my max voltage on my new drivers is 160VDC so ill be backing down to 140VDC to help protect them.

Old driver card (right) VS. New driver card (Left):
[attachimg=2]

So I stripped out the control box and pulled the mounting plate from the bottom.  Next I cut off all the original mounting studs but left the fan, I figured I could use it in the original location.
[attachimg=3]

Then I started laying out the new components and setting up new mounting points:
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The three smaller boards are the braking circuits.  Basically when the motors are braking they can create excess voltage and kick it back into the system, those boards will switch on and stop that excess voltage from making it back into the drivers.

Once I had the drivers and braking boards mounted I threw the plate back into the box and started looking at how I wanted to mount the motion controller and break out boards.
[attachimg=6]

[Dvous]

So I bought the C62 board for a variety of reasons but one of the big ones is that it plugs directly into the ESS motion control board via two 26 pin parallel ports.

ESS board on the right, C62 Board on the left:
[attachimg=1]

You can see here the C62 board has a metric ton of jumpers and I/O's.  It can handle coolant, VFD spindle control, Pendant Input, Air cooling solenoid control, limit/home inputs, and the list goes on and on and on.
[attachimg=2]

I decided to mount both of these boards on the side of the control box, so I drilled a few holes and got some nylon spacers to get it away from the wall and isolated as best as possible.
[attachimg=3]

Next I figured I would start setting up all the wiring and see of I could power up the boards.  First thing is the main RJ45 connectors from the C62 Break out board to each servo driver.  CNC4PC has custom pinout adapters to connect these (as it turns out I had them plugged in backwards in this pic lol, more on that later).
[attachimg=5]
[attachimg=4]

And started wiring all the rest of the functions, Power into the drivers, Power to the motors, 12v power to the break out board etc etc.
[attachimg=6]
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And after this point I was able to power the system up for the first time.  I cant even begin to cover the amount of errors I had in setup at this point lol most of those LED's are for errors.
[attachimg=8]

[Dvous]

So at this point I struggled for probably 5 or 8 hours getting all the jumpers setup right on the C62 board (one big thing was I had the jumper set to look for a pendant, which would be giving an E-stop input).  Ill skip over the details of the long arduous battle of getting the C62 board, ESS, Drivers, and Computer to all communicate.  If anyone wants to know any details just ask and i'll get into it.

So around this time I got my computer and monitor for this setup ($80 from newegg for the refurb lenovo computer and $40 for the refurb monitor, cant beat that)
[attachimg=1]

And I started downloading all the plugins and programs I would need to get this working, starting the the servoconfigurator software to tune the PID motor loop.
[attachimg=2]

And finally I downloaded a demo of Mach4, You download the demo and then buy a license file and they send you a key to type into the demo.
[attachimg=3]

Next I pulled the motors off my machine and brought them inside to start tuning the system.  I also pulled the C62 and ESS boards back out to make wiring changes easier (this was during the week or so of messing with the system trying to make it work right).  Notice I have the ethernet adapters plugged in the other way, into the C62 side, not into the motor side. Doh!
[attachimg=4]

Another problem I had was I wired the motors slightly wrong, once I had that sorted I could start tuning the system.  To start will that you use this little PRG01 programming stick to plug into the drivers one at a time:
[attachimg=5]

And finally I had the whole system assembled for the first time.
[attachimg=6]

[Dvous]

So step one at this point is to tune the PID loop for each driver/controller combo.  Basically when you try to move the motors manually they need to resist that movement via varying amounts of torque.  I honestly don't know too much about the details of the parameters but after reading some direction supplied by CNC4PC I came up with something I could live with for now.  To start off the motors were constantly searching for position on a never ending basis, In the pic below you can see when the line levels out the motor has reached its final position, at first it never leveled out and would just twitch constantly.
[attachimg=1]

So I had to repeat this process for each motor.  That seems simple but it really took about 8 hours, it's a lot of trial and error.

Once I had the motors tuned I was able to open Mach4 and freely jog the motors around on the table.

[digitalsolo]

This is sooo cool.   It's like nerd porn.      The 3D Printer Dork inside of me really digs how similar these things are.

[frijolee]

How's the documentation that comes with the new controller and boards?  I want to do this but the amount of background research I'd need to do is intimidating.  IE...  If you know these things and it still took you days of setup, so likely is an amateur to get it done at all?  Are the specific forums or user groups that are helpful in troubleshooting?

One more, potentially stupid question: Does setting up a Bridgeport as a CNC affect use of the mill manually at all?

[Dvous]

How's the documentation that comes with the new controller and boards?  I want to do this but the amount of background research I'd need to do is intimidating.  IE...  If you know these things and it still took you days of setup, so likely is an amateur to get it done at all?  Are the specific forums or user groups that are helpful in troubleshooting?

One more, potentially stupid question: Does setting up a Bridgeport as a CNC affect use of the mill manually at all?

I'm no expert in this field.  I know quite a bit about BP's due to owning one for some time and doing lots of research into them, but I haven't ever built my own CNC before this one.  The extent of my CNC experience is through my job as a mech. engineer.  It took me so long to sort out certain things because I had to go back and fourth with Arturo Duncan at CNC4PC.com hundreds of times to get this all sorted out, now that guy knows his shit!  Long story short, don't shy away from it, doing something like building a swap car is a much larger and more difficult process with lots more research. 

With that said, how many guys here are actually interested in a project like this in the future? (chime in here if you are).  the reason I ask is because Arturo and I came to the conclusion that it would be nice for someone to do an actual "write up" of the first few hours of running the controller to document all the stupid little things you need to look for.  The reason for this is he answers tons of questions about this particular setup (CNC BP) and if he could divert some people to some kind of source like that it would help everyone, and I'm going to do it because without him I couldn't have built this.  So, if you guys want I would be willing to add a long winded write-up to this thread which would make it easy for anybody to duplicate this setup and have it up and running in minimal time.  Besides that, like I said before I would be more than willing to help any one of you get on you're way with a project like this, just as you've all helped me with my FD for over 5 years now...Norotors is the best forum I've ever been a part of and I have no problem paying the help forward as much as possible.

EDIT: also, explicit direction could be used to help you build lots of things as Blake pointed out...3d printer, CNC router, CNC lathe, CNC plasma cutter.  This control setup COULD do all of that.  So let me know if any of those projects interest you and I'll go further into the nitty gritty of making this work.

As for you're last question, it depends on the kit you use.  Mine can be run manually.  BUT once you realize what you can do with a CNC I doubt you ever will.  Just because its CNC controlled doesn't mean you have to write a program...Ex. You just want to face .125 off an aluminum block, use the pendant to set your Z height via jogging mode, set your speed, and jog back and fourth just like you would crank the handles...except without cranking handles!

[frijolee]

Yes please on the detailed write up for initial setup.  That sounds like a GREAT idea to me.  When someone else who I trust as a third party as done all the research and makes something straightforward, I value my time highly enough to skip the research and instead just replicate the setup.  I know there are plenty of guys like me and that makes it good business sense for your vendor to support the effort as well.

Manual mode would be important for me as the only way I could fit this in my garage is if it replaced my full size drill press.  Also cranking by hand, or even using an autofeed, I can more easily judge on the fly whether I want to speed up or slow down the feed rate based on the chips and noise it's making.

[ls3_rob]

 

I am way over my head in here

good work but no idea what is going on