Topics

31

General Mach Discussion / changing kernel speed and maximizing travel speeds ?

« on: May 03, 2008, 07:32:33 PM »

I am finishing up my large (30hp) cnc lahe retrofit and I have a few questions about tunning for the highest possible rapids on the x and z axis with Mach . I am using 2kw, 3 phase brushless AC servo motors and matching drives from Automation Direct. Doing the math with their servo-sizer software my setup should be cabaple of rapids in excess of 1000 IPM  . Using the out put signal from another machine with Yaskawa PLC I was able to easily run the x and z axis at a sustained 800 IPM with no problem , motors and drives never got above room temp

I would like to use mach3 with this machine , I have installed the c11 breakout board from cnc4pc and mach 3 , the x axis requires 90k pulse per inch and the z requires 50k pulses per inch . With the kernel speed set at 45k hz the maximum IPM that can be input x axis is 30 and the max for z that can be input is 52 IPM . The software will not allow me to type in a larger value. The machine seems to run fine at these speeds but is painfully slow. If I change the kernel speed to a higher value I can then change the IPM in motor setup to a higher value but when I try to move the machine at anything over aprox 65 IPM the motors run in pulses , pause and then run , stopping and starting at regular intervals. The motors are not stalling , its as if the drives are receiveing the steps in burst with a pause in between.

What do I need to adjust or experiment with to get rapids of at least  400IPM? Could this be an issue with the computer or memory? its a p4 2.6 ghz

32

General Mach Discussion / Sure Servo drives with Mach

« on: April 10, 2008, 05:23:13 PM »

Anybody here using the sure servo ac brushless drives from Automation direct with mach? Which pins on the sureservo do I attach the step, direction and common pins from my breakout board to?

The wiring on my encoders are labled A , -A   B, -B etc  , the encoder inputs on the drive are labled A, /A and so on  , is -A the same as /A ?  Thanks

33

General Mach Discussion / m3 not always recognized

« on: March 18, 2008, 11:52:48 PM »

I am running mach on 3 machines, 2 lathes and a mill and at some point on everyone of them the m3 command fails to start the spindle, wont work at the MDI line or in the gcode file. It usually happens later in the day after the system has been running 6-8 hours sometimes not for a couple of days. I am not sure what the common link is three seperate machines, three seperate computers all have the problem at some point. Closing and restarting mach doesnt seem to fix it . Always requires rebooting the computer.

34

General Mach Discussion / Duplomatic lathe tool turret with Mach?

« on: February 27, 2008, 12:04:53 PM »

I have a lathe with a bsv-200 12 station tool turret from duplomatic and I am curios if anyone here has had any experience controlling the duplomatic turret with Mach?
here is a link to the unit I have 

http://www.duplomatic.com/duplomatic/auto/uk/2/frame2_21.html

35

General Mach Discussion / controlling lathe tool turret

« on: February 18, 2008, 08:06:30 PM »

I am building a couple of multi station tool turrets for my 14x40 and 9 x 20 lathes and need advice/guidance on controlling them with mach. They will work pretty much like the turret on larger lathes, I will need to energize an air solenoid to push the turret forward off the indexing pins and then tell a servo motor # of steps and direction to turn to index to the proper tool called out in the m6 command line. How should I go about this ? Is there a plugin or macro already written for rotary tool turrets? thanks

36

General Mach Discussion / My next retrofit more pic added

« on: February 16, 2008, 09:30:22 AM »

here is the machine I am going to retrofit next http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=310021367668
any thoughts appreciated

37

General Mach Discussion / Lathe Turn wizard question

« on: January 21, 2008, 09:39:52 PM »

WHen I generate code with the the lathe turn wizard the infeed of the x-axis to the cut depth is a G0 command which is just fine when the tool is out beyond the end of the stock (Z+** ) But when the z start point is a Z negative value it would be nice if the wizard would generate the x axis infeed line as a G01 instead of G00 ., It would also be nice if the x ais infeed speed could be specified as a seperate value from the z axis feed value. On short files I have just been editing this manualy but today I generated a file to cut profile a large mortar bbl thats aprox 4000 lines with almost all the x axis infeed commands being at a z negative position. Is this an easy option to add to the turn wizard? thanks

38

General Mach Discussion / feed hold switch question

« on: January 09, 2008, 08:43:54 PM »

I am trying to finish up the re-fitt of one of my machines from desk to mach and I am down to just the cycle start switch and feed hold.
 
Looking at the OEM codes I see 1000 for cycle start , is setup of this switch as simple as assigning the port and pin  my cycle start switch is attached to at OEM Trig 1 in inputs/ports and pins along with 1000 in the hotkey window?

My feedhold switch is a normaly open latching type switch so in desk when its pushed in the pin its attached to is grounded and the feed is paused until the switch is pushed again , unlatching the switch and opening the circuit. is this the type switch needed to work with mach or do I just need a momentary like the cycle start and estop switches?

39

General Mach Discussion / Need a little spindle encoder timing help

« on: December 17, 2007, 07:56:48 AM »

I received the nice spindle encoder board from cnc4pc and have it wired to pin 15 on the cll cnc4pc breakout board.  I have a single slot .2" wide in a disk 3.7" in diameter.

I am getting steady but inccorect spindle spead readings, no matter what the actual spindle speed I get a reading from 200-280 rpms  , often the reading goes up when the actual spindle speed drops .  If I change the spindle speed from 300 to 800 rpms while the spindle is running by typing the new value in the rpm readout is very eratic djumping from the normal mid 200 rpm reading to as high as 1400 rms and then settleing back down to the mid 200's again.

Hopefuly this is just a wiring or configuration issue , the disk is as small as I can make it due to the diam of my spindle, right at 3" . It doesnt seem to matter if I set the input to high or low .

I did cut a test thread of 20tpi and it came out almost perfectly at 13 tpi

Any thoughts greatly appreciated

40

General Mach Discussion / spindle encoder options?

« on: December 13, 2007, 10:15:08 AM »

I am mostly done with my retrofit of a 13x40 import lathe and have everything up and working other than the spindle encoder. I am wondering if someone could help with a basic circut to use the infared emitter and detector part# 276-142 from radio shack . They are relativley cheap and avail just about everywhere