Messages

41

dspMC/IP Motion Controller / Setting up a touch plate for TLO

« on: October 22, 2015, 04:16:24 AM »

I have been using my dspmc controlled mill for about 4 years, and this week decided to implement a Tool Length touch plate.

The touch plate is working fine, after playing around with various resistors and schemes.

I wired one end of a 330 ohm resistor to a wire, which connects to the 24 volt buss. The input to the J4 board connects to the insulated touch plate surface, and also to the other end of the resistor. Reading the voltage between ground and the touch plate
surface is about 23.7 volts.
Touching the copper touch plate surface to a tool in the spindle turns on the digitize LED on the diagnostics page, so all seems good to go.

Trying to run a touch-off program in conjunction with the dspmc setting in the config seem to interfere. The machine Z axis stops properly, and backs off .050 as per program, and the setting in the dspmc config, but then the machine starts wandering off very slow in Y positive direction.

What kind of program is supposed to work in conjunction with the config settings in the dspmc settings?

John

42

General Mach Discussion / Re: new guy

« on: October 15, 2015, 05:32:04 PM »

Scroll down to the "Member Docs" section of this forum, and download the "MACH 3 TUTORIAL - SETTING UP A BASIC 3 AXIS MILL" pdf file. It is a clearly written, step by step  tutorial, with page examples showing all the many parts of the puzzle. In addition to the videos, this will have you up and running, with a total overview of Mach3.

43

General Mach Discussion / Re: Homing Position

« on: October 08, 2015, 03:25:20 PM »

Hi Brian:
Go to the "Member Docs" section of the forum, and download the pdf file; MACH 3 TUTORIAL - SETTING UP A BASIC 3 AXIS MILL

This is an excellent overview written by Henrik Olson showing all the basic steps necessary for Mach3.  He details everything, including the Home states, as well as how to set Soft limits with pictures of the Mach screens at each step.

44

G-Code, CAD, and CAM discussions / Re: Setting Z Floor

« on: October 06, 2015, 11:33:06 AM »

The "Soft Limits" setting does this for X,Y,and Z.

45

General Mach Discussion / Re: whats with the mini vfd's currently for sale?

« on: September 24, 2015, 01:25:12 PM »

I was at the Little Machine Shop "open house" last year. One of their high-end machines is the Tormach mill. The company reps were there, running parts on one the mills. I asked them where the machine was built; answer: CHINA. Their company headquarters is in Wisconsin if I remember. They just designed the machine. Their new slant lathe is also a China product.
I just bought a "RIGID" orbital 5" sander. Made in China. Further reading of the paperwork, the Rigid brand is just a name, owned by New World .... or some such international marketing machine. Same for Black & Decker, and most of the other big-names in power tools. My Bosch saw is "made in China."
My machine shop is in Los Angeles, and about one mile west is Santa Fe avenue, which used to be "Machinery Row", where all the machine tool makers had their western headquarters and major distributors; it is now clothing sweatshops, and distribution warehouses. The famous architectural marvel, "Goodyear" tire plant is now a mall.
If I need a cutting tool immediately, the closest place is nearly an hour drive. I now buy all my tooling on the internet.
This is the "de-industrialization" of the United States, started in the 1970's, and is government policy.

46

FAQs / Re: Weird Calibrating Issues!!

« on: September 10, 2015, 09:51:59 PM »

If the chain is the foundation for all distance traveled, that is a poor basis. The error in the chain will be accumulative. You would be better served with a rack gear on the table, and the servos driving a gear pinion to move the X and Y axis. Rack gears are made with a uniform pitch, and the rack is cut with precise distance tooth to tooth.

For example, if each link was 1/2", but to be more precise if might be .502 from pin to pin, +/- the manufacturing tolerance. If you pulled the chain tight and measured 10 links, your total distance would be 10 X .502=5.020 inches. The actual distance is .020 over 5", not very noticeable.
Now take 100 links of your same chain, and do the same test.  100 x .502 = 50.200 inches, or almost 1/4" over 50.000 inches. Very noticeable.

I hope this makes sense.

John

47

Third party software and hardware support forums. / Re: Servo drive recommendations

« on: September 10, 2015, 04:46:00 PM »

Hi Don:
This post is a few months old, but I just read your questions. I have an older mill, with probably the same drives and the very same Electrocraft servo's. The driver/Amps were made by WestAmp, now out of business since I believe 1992. This type of control is Analog +/- 10v with encoder feedback. In the day, these were very good drives, and would hold position well.
The big problem is getting the drives repaired when they malfunction. Even though it might be a single resistor, easily replaced, finding exactly what is wrong can be very difficult without the proper electronic equipment. I have been able to find a few used drives on Ebay, but that is hit or miss.

The mill discussed now uses a dspmc controller by Vital Systems, and it runs the older drives perfectly. I did have to change the encoders to the AMT differential to work with the controller, but is runs better now than the original controller.

Since doing the retro-fit to the older controller, I have since learned of a newer type of Servo motor/drive that is far better than anything I have yet seen, and it uses step/dir for an absolutely solid, precise control.

If I did another machine, I would definitely use the Clearpath servo's by Teknic. There are Youtube videos showing these motor/servo's with Mach3.

John
 

48

Third party software and hardware support forums. / Re: Yet another drive compatibility thread. Maxon 4-Q-EC DES 50/5

« on: September 10, 2015, 12:30:14 PM »

Have a look at some YouTube videos demonstrating the Clearpath brushless servo motors. This type of motor is a huge quantum leap in engineering design over steppers motors and various types of basic servo motors.

The Clearpath motors do not use a separate driver like all other CNC control motors. The step and direction signals are wired directly to the motor and it has internal electronics including an encoder disc. The setup is through a built in USB port, which runs a software program on your PC to automatically set all the parameters of the motor.
The selection of motor sizes is NEMA 23, and NEMA 34, with a separate DC supply from 24 to 75 volts.

https://youtu.be/yZJVXTaDeoU

https://youtu.be/Bb6QK_-I_CQ

https://youtu.be/VaIEMNaSfy0

Here is the company video demonstrating the motor.
https://youtu.be/gz9mZ5fBwUM

John

49

General Mach Discussion / Re: Mach3 tablet controller

« on: September 03, 2015, 02:34:01 PM »

You should correspond with the maker of the wireless pendant to make sure it will operate on the Android system. Twenty feet away from the machine seems like an unusual requirement for CNC machine operation. I have one of the Vista wired pendants, with an LCD screen; well thought out, and solidly built.  If you have not tried it, the 2010 Screen is a huge improvement over the standard Mach3 screen, and I believe there is an Android version available. With that screen, and a Bluetooth keyboard, you may find it unnecessary to invest in a wireless pendant.

John

50

General Mach Discussion / Re: Mach3 tablet controller

« on: September 02, 2015, 12:18:53 PM »

There are a few tablets that run Windows, and they all will run Mach3, except Windows RT. The 12" tablets are pricier than the typical laptop, but with a USB multiple connector, they offer a very compact solution.