z axes lifting

[John Teichman]

Here is a problem i am having w/z axes i think it may be in settings in mach i cut all my 2d files perfect small 3d files ok but larger 3d files w/ alot of z axes movement starts to lift z about 1/3 to1/2 way into work. does not do this all the time. i have changed controllers to geko 203s because they were to hot now ok i am running @ about 100ipm. any replies will be appreciated.

[RMT]

Some Gecko's need a certain amount of time between the dir signal and step signal, if the step signal comes too fast they missed them and therefore don't execute all of them, try changing config>motor tuning >step pusle / dir pulse
to 5us .

Frank

[redeft]

Hi, I have the same problem and it is driving me batty!
Sometimes the z rises every so often so that half way through it is cutting air. It is a (http://www.microkinetics.com/Drakspec.htm)
microkinetics drive rack but I just cant figure out why sometimes it works and other times it doesn't. It also sometimes slows way down and gets slower and slower as it goes along.

Any ideas on what my problem is?

Thanks, Peter

[LeeWay]

Have you guys tried reinstalling Mach 3? You may also need to redo your configuration if it isn't too difficult. I find this helps sometimes.
I had a problem where the Z would just creep at snail pace back down to zero after it's initial safe Z move. Then once down to zero, it would jump back to safe Z and start the cutting as it should have to begin with. I had to reload mach and start a new config file, but haven't seen this issue since. It was doing that for every file and I know there was no code telling it to do that.

[Khalid]

seems electrical interference...check the thread post No. 513
http://www.cnczone.com/forums/showth...t=39588&page=8

[redeft]

I came across this in my search for the cure for this problem. I use cnc file extension not nc but I am not sure if this is the solution. Can anyone explain this more clearly? I have checked the wiring and dont think that is the problem,although I could easily be wrong.


"I have had this problem with an Australian Multicam machine running 'Toolpath' software to output to the machine. The file is imported from ArtCAM as an AXYZ style .NC file.

The machine does as you describe when larger files are sent to the machine. The Toolpath program breaks them up into a series of contours, and the Z height change occurs when moving from one contour to the next. (but not always). It can change either up or down.

The cause of this problem is that the Z depth entered into the machine at the keypad (ie depth to machine below the top of the material) is less than the Z depth included in the file sent to the machine. You may have a piece you have designed at 10mm Z height, and sent it to the machine saying go to a depth of 10.5mm. Unfortunately, the file includes the safe Z height of say 3mm, so the file is actually 13mm deep.

The answer is to open the file in the Z view (if using Toolpath/view/3D view - change X to 90 degrees, Y to 90 degrees and click GO. The image on the screen is a side on view, and by clicking on it, you will get a Z height shown in the bottom left hand corner of the screen - in this case 13mm."
Set your Z depth on the machine to 13.1 or greater - as long as it is deeper than the file depth, and problem solved. I have not had a crash since using this method.

[redeft]

I forgot to mention that I don't use Mach 3, I use millmaster pro from microkinetics.