Messages

11

General Mach Discussion / Re: CNC4PC C11G Analog Output Spindle Control

« on: December 01, 2009, 11:51:43 PM »

Thanks all for the help, it looks like I am going to need to mess with it a significant amount of time to get things up and running, that is the way these home-made machines go :-)

Pete, are you referring to the coolant pump wiring?  If so  one of the relays on the C11G should do the trick  per GrandMasterB, but note the rated contact current and voltage.  Is your coolant pump AC?  If so and you are using the relays for something else you can get solid state relays for switching AC loads that are reasonably cheap, and the input will operate off of the 5V from the bob and you can switch 110-240VAC depending on what relay you get.

Hope that helps,
Dustin

12

General Mach Discussion / Re: CNC4PC C11G Analog Output Spindle Control

« on: December 01, 2009, 04:40:19 PM »

Hmm, Having trouble with this.  I just hooked up the 10V to the C11G because I measured the draw at @ 14mA so figured it would not hurt anything.  It sort-of works, but it takes a long time for the speed to stabilize, and it seems to be super non-linear.  Also, it seems to have different speeds depending on if you are increasing S or decreasing it.  IN other words if you type in 50, then 100, then 150, etc you get different results than if you go backward from say 500 to 450, to 400 etc.

I have it set so that 8V is the maximum and this does not seem to saturate the F-V converter. 

Suggestions?

Thanks,
Dustin

13

General Mach Discussion / CNC4PC C11G Analog Output Spindle Control

« on: December 01, 2009, 01:02:51 AM »

Hi All,

OK, the next step is to get the spindle working with Mach3, now that I have the index pulse properly setup to read the speed.  I have a C11G BOB from CNC4PC and I am not sure how to proceed, here are my problems:-)

1- The VFD I am using ( a 15HP GS3 from automation direct) has an analog output supply of 10V at 20mA max.  The C11G has a required input of 12V @50mA.  Do I really need another isolated power supply?  I feel like I have about enough in that control panel...  24VDC, 24VAC, 12VDC for the drives, 60VDC for the servos, and on and on.....

2- Ive read some not so encouraging things about the C11G's analog capabilities after purchasing it quite some time ago, if I go to the trouble of setting up another PS, will it even work?  Has someone out there had success with it?  I have 4 of their boards going right now and all the other functionality seems OK, although I had to return one for workmanship issues (pins bent over on IC) and they always look a little funky right out of the box...

Does anyone have any suggestions as to how to proceed?  I am seriously considering just switching over completely to Peter Hommans boards and use the C11G in my other lathe which is currently BOB-less.

I've recently received a big order for parts and am feeling the pressure to get this retrofit done, but want it done right :-)

Thanks for any suggestions,
Dustin

14

General Mach Discussion / Re: Index Pulse, nothing happens in S True DRO

« on: November 30, 2009, 11:16:58 AM »

Daniel and Peter,

Thanks for the suggestions, I have it working now!  I did have the feedback option checked but I did not have the "disable spindle relays" box unchecked, that did the trick!  And indeed, the Mach must think that the spindle is on for it to register the speed.  The next project is to get the VFD talking to Mach...

Thanks again,
Dustin

15

General Mach Discussion / Index Pulse, nothing happens in S True DRO

« on: November 30, 2009, 01:43:28 AM »

Hi All,

This is probably something simple but I am not figuring it out...  I am trying to set up the index pulse on my Takisawa lathe and just cannot get Mach to display the spindle speed.

It is a one-pulse per revolution encoder, and I have electronically lengthened the pulse to 20ms.  This gives me a nice ~50% duty cycle square wave at ~1500RPM.  It is also adjustable so I can decrease the pulse width to something shorter if I ever get it working :-)

So, my setup is this-  I have pin 10 of port1 set as the Index input, it is set to active high and the pulse is 20ms high every 1 revolution.  The index (virtual) LED lights up in Mach every time, and the (actual) LED on the CNC4PC card lights up every rev too.

The problem is that nothing happens in the spindle speed DRO.  I have it setup just like (I think) my other lathe running Mach (A different version) which will cut threads all day :-)

Any ideas?  It is probably just a check box somewhere, but it is starting to drive me a little nuts:-)

Thanks so much for any suggestion,
Dustin

16

Show"N"Tell ( Your Machines) / Re: 1979 Takisawa DTX-1 Turret Lathe Update

« on: November 25, 2009, 10:29:14 AM »

Hi Tweakie,

Thanks!  I am glad I spent the money to have everything powder coated, it was worth the $800 just to not clean the grime off of it, let alone paint everything!

I picked up the lighthouse thingy last time I was at the surplus store for about nothing, currently is just indicates that the panel is live (the service breaker is on) so I don't accidentally go sticking my fingers in there at the wrong time :-)  I have not decided what, if anything, to do with the rest of it...  Suggestions?

Dustin

17

Show"N"Tell ( Your Machines) / Re: My CNC pressbrake build

« on: November 24, 2009, 09:58:47 PM »

Beautiful parts, it will be great to see how the project comes along.  On your 6-jaw chuck, what do you call those pads on every other jaw that act at parallels?  That would be amazingly handy, I'm not sure how I've gotten by without that!!

Dustin

18

Show"N"Tell ( Your Machines) / 1979 Takisawa DTX-1 Turret Lathe Update

« on: November 24, 2009, 04:10:40 PM »

Hi All,

Here are a few more images of the lathe project, I thought you might be interested!  The turret is up & running, the servos are tuned and working great, and the spindle, way lube, spindle oil, and coolant pumps are all on-line.  I still need to interface the spindle drive with mach, and get the index pulse working....  Among other things :-)

Thanks for looking!
Dustin

19

General Mach Discussion / Noise, external e-stop triggering, grounding

« on: November 24, 2009, 12:13:25 AM »

Hi All,

I've been working on my Takisawa lathe for a few weeks now and am making great progress thanks to Hood, Peter and others.  I was having a noise problem and finally fixed it and wanted to share what fixed it for me in case someone else has the same problem.

What was happening is whenever the spindle was on I would get intermittent false triggering of my external e-stop, and I had some major problems with the computer dropping the USB keyboard connection.  It turns out if the keyboard disconnects while jogging, it keeps jogging (E-stops are good :-)).  Replacing the keyboard made that problem go away, but I was still getting false e-stops all the time even with de-bounce set to 2000.  The computer was plugged into a separate 110V outlet from the rest of the lathe so I knew that the two grounds were probably at substantially different levels, and the noise on one would not be common with the other.  So I decided to run the PC and monitor off of 240V, which almost all monitors and power supplies have an option for.  I lopped off the 110V US plugs and just wired it right into an existing circuit with a breaker inside the control panel, and grounded them to the main tie-point.  No more problems, so far :-)  Everything on the whole machine now runs off of the 240V 3-phase coming in and has a SINGLE nice solid ground back to the service.

I'm sure there are a zillion ways to fix noise, and it is more black magic than science (if you ask me...) but this worked way better than I thought it would so thought I would share.

Dustin

20

General Mach Discussion / Re: Lathe turret, VB, PLC, MODBUS, Position

« on: November 21, 2009, 02:17:35 PM »

Hi All, just a quick update on the tool changer, it is working really well!  I have  it up and running with everything but the clamp going, I don't yet have all the hydraulics installed and ready to go.  I've attached the macro just for fun, I had a good time writing it, and it is really cool to see it working :-)

Thanks for all your great help!!
Dustin