Messages

1

General Mach Discussion / Re: Noise Issues causing all sorts of problems

« on: June 10, 2011, 01:20:20 PM »

thanks guys for the support.

rrc1962,

I'm leaning towards removing the Smooth stepper also, can you recommend a breakout board that is compatible with the G540?

or is it even necessary?

OH!, I was careful to not use relays, only solid state relays.

2

General Mach Discussion / Noise Issues causing all sorts of problems

« on: June 10, 2011, 11:08:54 AM »

I am having what I guess to be noise or interference problems.

Most common is a random "external e stop requested"

however I also get a random resetting of my Z position. That is to say I will home the machine, then as I run the program it (Z readout on the DRO) will suddenly change, and not once has it changed so it didn't drive a tool down into my work.

it has twice changed in the middle of a program while it is running.

Just last night I was trying to carve an intricate logo on to a polished aluminum billet 12x 18 x1. I used the probe to touch off the surface and set my Z .100" higher than the surface and ran an "air cut"

The program ran well was centered. I rewound the program, sent the head to Z 0.000, entered .100 on the DRO, homed the machine  and when I started the run it dove full speed into the face of the aluminum with enough force to spear the bit into the billet and shear the mill head off the mount. After I cut power to the mill head and hit the feed stop, the Z DRO read at -4.6293,

I built my controller from a smooth stepper and Gecko G540.

my limits are optical and I have a 1uf electrolytic already between the ground and supply feeding the limits.

I've set my debounce to 20,000! and I still get the external estop request.

I've completely eliminated my Estop circuit and wired a jumper between my 48V power supply(-Vdc) and pin 10 of the G540.

the 3 internal power supplies have all the negative terminals daisy chained and sent to ground, the earth ground is no where near the chassis ground.

as far as I can tell I have no ground loops ,I build guitars and amplifiers and I am very familiar with ground loops.

I've COMPLETELY removed all 120 VAC wiring from the controller box (mill head and router head power) and re routed them to drop down off the ceiling and at 90degrees to the controller and the wire routing.

the circuit that the controller is powered off of is on its own breaker and has a separate ground rod 12' away from the shops ground rod. The computer, monitor and external hard drive are powered off this too as not to cause a ground loop.

I'm down to two other possible sources:

There is a large 6 bulb fluorescent light fixture maybe 4 feet from the controller .

Maybe the shop power has interference? the power lines  run under high tension lines about a mile up the road. I'm VERY rural and am the last house on this grid with the the last pole sitting in front of the driveway and the power lines terminate on it.

I am at my witts end here.


Ray

3

Tangent Corner / Re: what kind of liner motion ways are these?

« on: April 21, 2011, 07:03:31 AM »

THANKS!


Yeah, you can see they are hard to keep clean. The x and y are protected with bellows, but get fairly dirty quickly.

When I had the Y axis tore down and no ball screws attached, I could tap the table and send it to the far end.

The machine started life as a CMM, BIG 4' x 4' granite table 9" thick, and the fixed gantry is 3" high, stretches the width, has a 24 1/2" opening for the Y to pass through and is 12" thick.

The guys who delivered it said I weighed 2,750 lbs without the  4x4 steel base

4

Tangent Corner / what kind of liner motion ways are these?

« on: April 21, 2011, 12:54:59 AM »

This is the  LM ways on my machine.

Id really like to be able to know what type they are.

They are mfr'd by THK, but I have poured over their site and could find no reference.

Thanks
Ray

5

General Mach Discussion / Re: home and limit setup questions

« on: April 20, 2011, 01:51:20 PM »

Some more successes!

My Z-- had a cold solder joint on the connector pin, The Z axis homes as it should as does the rest.

I have been also been thinking that the "backup" is how far the axis moves after it hits the home, It is as I found out the G73 peck drilling back out, so when I changed the number it did not affect my home routine,

go figure!

thanks for the Help fella's

Ray

6

General Mach Discussion / Re: home and limit setup questions

« on: April 19, 2011, 12:23:42 AM »

  OOPS,

I should have figured a software company would have paperless docs.

I'll DL in the morning when I have fresh eyes.

Thanks for those links!

They might help me to keep from exposing my NOOB too much!

I tricked the Z limit and  cut a few air parts, all the axis' move the way they should and the X and Y limits perform the way they should too. It was VERY exciting to see the whole thing in motion with the steppers whining and all!

I set the "backoff" on the setting screen to .2" and the X and Y back off as they should, But the Z still overtravels the limit and when I trick it it does not back off. I thought that may it was backlash as the Z axis is a trapezoidal acme, but I did not see the motor shaft reverse and move before the Y went into its homing routine. I think I'm missing something very basic here.

And when the table is jogged into a limit, I cannot reset  Mach and make it jog off the limit like it does in the Home routine.

The prox signals are landed at pins 1,2 and3 of the G540 and they are read on the Diagnostic screen. I slowed the Z axis motor a lot in the motor tuning screen thinking it may have just blipped past it, but it did not help.

When I jog to the Z into the limit it trips fine, And it moves MUCH faster when I jog that it does during the Home routine.

I'm thinking if I put a diode on the end of each of my prox signal wires, I can tie all the  --/Home limits to one input on the G540 and not worry about feeding back a signal into the other proxes. it might drop the high to around 4.5V and the low to 0, but the board seems to trigger around 4V

Ray

7

General Mach Discussion / Re: home and limit setup questions

« on: April 18, 2011, 08:56:02 PM »

Thanks for the info Ron, I'll double check all that.

As far as a manual goes, I never recieved one with this machine when I bought it.

It's a project that someone else quit on.

this is how I have it wired so far

8

General Mach Discussion / home and limit setup questions

« on: April 18, 2011, 04:56:43 PM »

Total noob, so bear with me please.

I'm making progress landing everything, motors and limits and such,

I'm running Mach 3 into a smooth stepper and then into a Gecko G540.

when I go to home  the machine it goes past the Z--/home limit till the Z axis binds.

If I jog the Z it reads and stops.

If I hit the Estop, and then reset it the Z it will act as if the Z home switch was made and continue to do the home routine, with the X axis moving to the limit then backing off then the Y axis does the same.

Also, If I jog into a limit switch, I have to shut the machine off and move the axis by rotating the ballscrew with a pair of pliers until it is off the limit before I can reset it, is there a way around that?

9

SmoothStepper USB / New setup with SS and G540, total noob,lots of questions

« on: April 17, 2011, 04:28:10 PM »

Hi,
I'm new to all this stuff, CNC, Mach 3, everthing.
I acquired someones project that was setup with Mach3 and drove servos. after finding out servos were not the best fit for my application, I bought stepper motors, a G540, Smooth stepper, and a 48V power supply to retrofit in the machine.

So now I've installed the motors, made cables, (controllers are just mounted to a board till I make a suitable cabinet to house it all), figured out how to make the optical limits work and now I don't know where to land the signals from the limits.

The optical limits are NPN and go from an active low of about a half volt to an active high of 5V when the flag breaks the light beam.

I've attached a sketch of my wiring so far.

Besides not knowing where to land the signal wires from the limits, I have a few other issues.

when starting up Mach, I get a message estop not assigned to smooth stepper. I click the window and click reset on the screen and the message appears again, then I click it again and it goes away. If I hit the Estop, the red fault light goes on  on the G540, but Mach doesn't show that an Estop is active.

The other thing is when I move the X axis .500 inches (according to the screen on Mach) I have only 0.3965 movement of the axis (as read by my test indicator)

any help will be greatly appreciated.

Ray