Messages

31

General Mach Discussion / Re: Using a PWM signal to run an ESC controller for RC outrunner spindle motor

« on: May 23, 2013, 05:05:48 PM »

Mike,

Hey thanks a lot,  I will check this out. 

Zarzul

32

General Mach Discussion / Re: Using a PWM signal to run an ESC controller for RC outrunner spindle motor

« on: May 17, 2013, 02:07:22 PM »

That is the problem,  the ESC controller takes a hybrid type of PWM. 

Since I am using this for engraving and PCBs the high speed works pretty well.

Thanks for your insight, the info on poor turndown is very useful.   I wonder if these could be run from a different type of controller?  Like a DC servo motor controller with encoder like you suggested?

33

General Mach Discussion / Using a PWM signal to run an ESC controller for RC outrunner spindle motor

« on: May 16, 2013, 03:49:09 PM »

Has any had much luck using a PWM signal to run an ESC controller for a RC plane outrunner motor as a spindle.
I am trying to do this but having some difficulties.
The PWM is a little different for the ESC controller. 

This is a description of how they work.
DC ESCs in the broader sense are PWM controllers for electric motors. The ESC generally accepts a nominal 50 Hz PWM servo input signal whose pulse width varies from 1 ms to 2 ms. When supplied with a 1 ms width pulse at 50 Hz, the ESC responds by turning off the DC motor attached to its output. A 1.5 ms pulse-width input signal results in a 50% duty cycle output signal that drives the motor at approximately half-speed. When presented with 2.0 ms input signal, the motor runs at full speed due to the 100% duty cycle (on constantly) output.

I have had some success by doing an odd ball start sequence where I start the spindle and call for 50 rpm which gives me a 1ms pulse width, then a pause to allow the ESC to initialize, then I call for 100 rpm (scale of speed is 1000 rpm) and it will run 2ms pulse for full speed on the motor.
 

34

Show"N"Tell ( What you have made with your CNC machine.) / Re: MODEL 629 S&W MAGNUM

« on: May 07, 2011, 03:38:53 PM »

Tweakie,

I am almost sure that is not a casting,  it probably looks like that because of the failure mode,  brittle fracture can look like that.
Sure glad I wasn't holding something like that it when it went off.

Arnie

35

General Mach Discussion / Re: How to control air-solenoid valve with mach3 ?

« on: May 07, 2011, 12:28:05 PM »

Ton,

What function does your solenoid perform?  Coolant?  Vaccum?  Z axis? 

Arnie

36

General Mach Discussion / Re: Axis' accumulating error - need to emulate Mach3 output for testing

« on: May 07, 2011, 12:23:38 PM »

Scott,

I had this same type of problem with a New Hermes engraver that I converted to run from Mach3,  The opto were too slow. 
It manifested the problem by climbing in the z, x & y axis all in one direction. 
I was doing some text engraving and the letters ran at an up hill angle, getting lighter and lighter, and closer and closer spacing.
Since the driver board was all TTL circuits I simply jumpered out the opto isolators.

37

Show"N"Tell ( Your Machines) / Re: 13x40 lathe conversion

« on: March 19, 2011, 10:18:09 AM »

Pete,

Yes the 12x36 is almost a twin of the 13x40.  I ended up using motorcycle fork boots for my ballscrew cover,  the screw is almost 1 1/2",  I got a unbelievable deal on ebay for it.   I had to sacrafice a few inches of stroke but it was worth it.  I haven't made a lot of big projects with it, mainly parts of other projects,  mostly milling stuff,  I did bore and thread an AR15 upper receiver.  It just love the ease of threading, any pitch, right up close to a shoulder you name it, it is a breeze. 

Yes I use the existing bolt holes for the apron.

You should dive in on your conversion,  once you get done you will wish you had done it years ago.

38

Forum suggestions and report forum problems. / can't edit my old posts in bargain basement- Benny Help?

« on: March 05, 2011, 10:17:17 AM »

I know I used to be able to edit my old posts in the bargain basement but either I forgot how or I don't have permissions.
I believe there used to be an edit option next to the reply option.

any help?

39

Works in progress / Re: 3 PAGE LATHE SCREEN - WIZARD ADDITIONS

« on: November 30, 2010, 03:33:57 PM »

I have some additional wizards that you can use for your new screens.  I posted these quite some time ago, feel free to include any of these you like.

http://www.machsupport.com/forum/index.php/topic,4206.0.html

Arnie

40

Show"N"Tell ( Your Machines) / Re: 13x40 lathe conversion

« on: September 13, 2010, 08:00:52 PM »

I did get a speed pickup mounted and have been doing some threading,  seems to work just fine although I am using an older version.   .034 or something like that.

Also just finished installing a VFD,  my Harbor Freight motor died,  bad starting cap.  I had more trouble troubleshooting it to the cap than it took me to swap to a 3phase motor and vfd.
I went through the relay starter with a fine tooth comb until I discovered the leaking cap,  had that thing apart 6 times before the light came on.  Half the wires in the relay start/reverse were poorly connected, half loose, the relays were designed for larger wire and would not crimp down tight on the small guage wire they used.  That lead me down the path to thinking loose wiring.