Messages

1

General Mach Discussion / Re: Losing Steps????

« on: January 29, 2010, 05:55:26 AM »

How are you 'removing backlash'? Sounds to me like you have a problem with your testing proceedure.

By 'removing backlash', I meant that I made a small move in the opposite direction to 'take up" the backlash ~.0015" that the X axis has.  I did this so that the backlash wouldn't effect my measurements.

Tom

2

General Mach Discussion / Re: Losing Steps????

« on: January 29, 2010, 05:53:33 AM »

Check that you have no loose pulleys, failing that I can only think it is a problem with tuning or a drive.
Hood

Checked the encoder attachment set screws they were ok, no pulleys it's direct drive, swapped drive with the Y axis drive, no change.  could I have a defective encoder, I have another one, would it make sense to swap it?

Tom

3

General Mach Discussion / Losing Steps????

« on: January 29, 2010, 02:55:23 AM »

I am having trouble with my mill, it seems that I am losing steps.  The mill is set up as per my signature.

I am using an indicator mounted in the spindle, I zero out the indicator on a bar clamped to the table parallel to the Y axis, making sure to remove any possible backlash.  I then make a G1 move in the X axis of -2.953" (75mm) and then insert a 75mm Jo block.  With the feed rate set to 4 IPM the indicator reads .000.  I then remove the backlash and rezero my indicator on the Jo block, remove the block and make a g1 move in the X axis back to 0.  The indicator will read -.0015.  I did this 3 time at this feed rate and had the same results.  When I increase the feed rate to 6 IPM, I get an indicator reading of -.001 on th first negative X axis move, but it is off --.035" on the move back to 0.  If I increase the feedrate to 10 IPM I get -.006" on the negative move and -.067" on the move back to 0.  If I do a G0 move it is off almost -.185" on the move back to 0.

I've do some limited testing in the Y and Z axis and don't seem to have any issue, the indicator reads within .0005" both directions.

Any idea what might be happening?

Thanks

Tom

4

General Mach Discussion / Spindle configuration setup

« on: January 22, 2010, 04:37:16 AM »

I need some help figuring out the proper pin and port settings for the VFD that controls the spindle on my mill. 

the mill is a Hurco SM1 I am using the factory servos, Viper 200 amps, Smoothstepper, CNC4PC C23 BOB, Durapulse GS3 VFD. C15 relay board.

I have wired the VFD using this diagram from CNC4PC...  http://cnc4pc.com/Tech_Docs/C23R2toVFD2.pdf

The CNC4PC site shows an example of the ports and pins setup that shows pin 14 as the step pin which matches the wiring diagram for the spindle speed output on the C23(analog) to the VFD.  The direction pin is where I need some help.  The example CNC4PC indicates pin 8 for direction while the direction (CW & CCW) is handled on the wiring diagram by pin 1 and pin 16 which are the 2 built in relays on the C23.  I only have 1 direction pin in the Mach setup screen, but have 2 different pins that appear to me to control direction (CW & CCW) going to the VFD.  What is the correct pin number needed in the Mach setup screen?

Also since I am controlling speed with the VFD how do I setup the spindle pulleys part of the Mach spindle setup screen?

Thanks

Tom 

5

General Mach Discussion / Hurco proximity style limit switch problems

« on: April 13, 2009, 08:26:02 PM »

I have a 1984 Hurco SM1 with the stock proximity style limit switches that were functioning prior to replacing the Hurco control with Mach3.  I am using a CNC4PC C23 breakout board, Smooth stepper, Viper200 servo drives.  The problem I am having is I have 5v going to the limit switches, as checked with a meter, but when I trigger one of the limit switches, doesn't matter which one, I don't get any voltage back from the limit.  I have attached a scan of the Hurco wiring diagram for reference.  Any help would be appreciated.

Tom

6

General Mach Discussion / Re: Steps per Unit

« on: February 10, 2009, 03:51:15 PM »

Hood,
Here is a post from Larken...

Step multiplier, Why use it ?

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

There seems to be some confusion by some people on what the step multiplier is for. Some people want the system to have the highest possible resolution of the encoder ( or encoder X 4 as in the viper) , so they want to run no multiplier ( 1 ).

On a servo system the system works off feedback error. If there is no error, then the drive puts no power to the motor.
Rarely under cutting and moving a machine with any friction can the drive keep a zero error.

On the bench with no friction or load, the motor will respond to a 1X multiplier, but on the machine and cutting, its just an illusion and requires very high steprates to get any speed.

On our machines i never run it less than 4X.

7

SmoothStepper USB / Controller(pulse) frequency

« on: February 10, 2009, 02:45:52 PM »

How do I determine the proper controller/pulse frequency?  The manual seems pretty vague when it come to this setting in my opinion.  I also need help with the max step frequency for each axis.  How is this determined?

Thanks

Tom

8

General Mach Discussion / Steps per Unit

« on: February 10, 2009, 02:38:04 PM »

Hi,
I am a little confused on the steps per unit.  I have a Hurco SM1, .200" pitch on my ballscrews, directly coupled to the servo on the X axis, 1-1 timing pulleys on both the Y & Z axis.  1000 CPR encoders on all 3 axis, Larken Viper servo drives that have the option of 0, 4, 6, or 10 step multiplier.  I also have a smoothstepper.

So...
My screw revs per unit = 5
Motor steps per rev = 4000
Mach 3 steps per rev =  20,000  (5 x 4000)

OK, does the step multiplier have any bearing on the Mach 3 steps per rev?  Larken recommends 4x multiplier. 

Thanks

Tom

9

General Mach Discussion / Re: New people welcome !! Come in here and introduce your self!

« on: February 10, 2009, 02:19:07 PM »

Hello,
My name is Tom and I am retrofitting a Hurco SM1.