[Ed3XP]

So I have another post on here getting my warthog up and running. Well its up and running great, other than this pretty major problem. Its not accurate. And not just a tuning problem, but for example, if I home the router, then move it around, and send it back to home... its off. and each time its off. in different directions. It happens to all 3 axis. I have a few pictures here so you can see what its doing. each time i take a pictures, i moved it, then sent it back to home. I am running gecko 201x with a PMDX 132. It is a rack and pinion system and the Z is on a ball screw. I doubt it has something to do with the actual motors, as it happens to all 3. Could it be Mach3? Its running at 25k and seems to be running perfectly normal. If anyone has any suggestions.. please let me know! Its driving me crazy.






here I'm trying to cut a harley logo, and it just goes everywhere... its off on all axis

[ger21]

What are your acceleration and velocity settings?
Cut them in half and see if it gets better.

[Ed3XP]

my acceleration is 50 and my veloctity was 350. I just now cut it all the way down to even accel 10, velocity 100. and I received the same results. It seems like its worse when i move both axis' at the same time and home it.

Could it be a wiring problem? What were to happen if you mixed up the A- and A+ (or Bs) on the stepper coils? Not saying that I did, but you never know.

Also, could it be a computer issue? It only does have 256 mb of ram. I am going to go upgrade it today hopfully to a gb.

[gmfoster]

Well it could be noise...

Could be back lash.

Could be the direction pin set wrong..I forget the details on this one but basically you lose a step on each direction change.

Could be a combination of all.

As I always tell people you need to start simple and get things working..

Go back and forth in one axis and get that working. Then move to the next axis and get it working. Now get a square working, then a diagonal thru the square and then move on to a circle...

When you think you are good engrave a grid, then cut it backwards. Many of these would be better done with a pen than a cutter...

But the thing is you need to find what isn't working and fix it.. Then move on.

If each axis works by itself but problems when you add axis then your power supply may be to weak or you have noise.

If everything works with a pen but quits when you have the router on its probably noise.

There are many things that can go wrong and they need to be eliminated in a systematic way.

The first thing I would do is go back and forth 50 percent of travel 10 times on the x axes. When I thought that was good I'd do 100 passes. I would then move on to the next axis and do the same thing. Now do the square then the diagonal...each multiple times.....ect.. When everything works then cut a logo!

Garry

[Ed3XP]

an upgade to more memory did not fix the issue. How can I check for noise? also i dont think there is any backlash, esp not enough to cause this much movement. that machine is solid.

[gmfoster]

an upgade to more memory did not fix the issue. How can I check for noise? also i dont think there is any backlash, esp not enough to cause this much movement. that machine is solid.

Well as I said before use a pen or pencil for the spindle. Then draw a line and see of it is repeatable. Use one axis.

Your spindle is the cause of the most electrical noise.

If you run only axis your will not be getting noise from the other stepper commands..

The easiest way is start simple see what works and go from there.

You can get electrical nose from the spindle. You can get noise coupled from other axis signals running parallel to each other...

There are a 1001 ways to get noise..

Improper grounding or bypassing.

Steps missed can cause similar problems to what you are seeing..

Have you tried the simple stuff?

Draw a line over and over does it work?

If you really don't want to start simple do your logo with a pen...
If that works its but it doesn't when you turn on the spindle then you have noise or missed steps...

[ger21]

There are probably 100 things that could cause this. RAM is not one of them. ANd neither is backlash.

First, how fast is your PC? Have you run Drivertest.exe? Do it and see if you get a flat line with no spikes.

What are the specs of your motors, and your power supply?

What current do you have the Gecko's set to?

Do you have a breakout board?

As the previous post mentioned, you really need to start with one axis and get it working correctly before moving on. Trying to troubleshoot 3 axis at once is not a simple task.

[Ed3XP]

all 3 steppers lose steps without the spindle on and when being moved individually. the line is always a little off each time.

the computer is a 1ghz mini itx. 1 gb ram, and its pulsing at 24860 and the lines is flat with a random spike here and there.

[Ed3XP]

im using gecko 201x and a pmdx 132 breakout board.

[ger21]

Motors? power supply? Drive system?

[Ed3XP]

power suplpy is a 700 watt power suply from antek, drive system is rack and pinion on the X and Y and Z is ball screw, and pictures of my motors are here...

http://www.cnczone.com/forums/diy-cn..._router_-.html

[Ed3XP]

still having this problem after rewiring the motors and checking the cables..... its happens when using each axis individually, but is much worse when moving more at once. this is quite irritating... on the pc, the frequency never drops below 25k when the motors are moving either.

[zool]

Is the parallel port on the motherboard or is it a PCI [add-on]card?

[Ed3XP]

It's a on board parallel port

[ger21]

Do you have the current set correctly for each motor?

You say it's worse when all 3 motors are moving? Open the task manager and check the CPU usage when the machine is running?

How fast is the PC, and what processor?

Again, I'd disconnect everything and get one axis working at a time.

[atwooddon]

deleted

[zool]

It's a on board parallel port

I suggest getting and installing a PCI parallel port card.

REASONING: The on-board parallel ports only put out about 3.3-volts. The PCI parallel port card puts out between 4.8- and 5.0-volts, which will be better for the controller. There are a number of threads on CNC Zone about this issue. I had problems with odd movements in the axes of my first CNC router and they disappeared after I installed the PCI parallel port card.

I have read about this in a number of places [which I cannot remember right now] so you might want to do a search on it.

[Ed3XP]

Do you have the current set correctly for each motor?

You say it's worse when all 3 motors are moving? Open the task manager and check the CPU usage when the machine is running?

How fast is the PC, and what processor?

Again, I'd disconnect everything and get one axis working at a time.

X and Y is at 3.4 Amps, Z is like 3.0.

The PC is a 1ghz unknown what kind. its a Mini ITX motherboard.

I agree on getting one axis working at a time, my question still is tho, how do i fix it? i have been running them one at a time, still has issues. I can move it back and forth all day long, and it keeps getting farther and farther away from the home pos. What exactly should I be doing, with each single axis, to try to fix it?

[Ed3XP]

I suggest getting and installing a PCI parallel port card.

REASONING: The on-board parallel ports only put out about 3.3-volts. The PCI parallel port card puts out between 4.8- and 5.0-volts, which will be better for the controller. There are a number of threads on CNC Zone about this issue. I had problems with odd movements in the axes of my first CNC router and they disappeared after I installed the PCI parallel port card.

I have read about this in a number of places [which I cannot remember right now] so you might want to do a search on it.

Well, since im running a mini ITX board, ill have to go get another computer and give that a try. It does output closer to 5volt though on the serial cable when i check it with a multimeter. Ill let you know my finding after i pick up another desktop today.

[zool]

Mini ITX motherboards generally run on 60 to 100 watt power supplies which means they may not have the amperage you need for CNC.