Help me please, strange vibration in z step motor

[Scramjet]

Hi, i finished building my controllers cards and interface board in accordance with the diagrams in the book of Geoff Williams "CNC Robotics, build your own machine workshop", the problem is, when i put in the Kcam registered program, all the directions and setup timing, the step motors work really fine with enough torq, but only in the X, Y the Z one starts vibrating instead a normal movement, i checked the connections, the voltages, the port setup, the controller card in comparation with the other two and everything is identical, dont know whats happening.

I pluged X and Y to a power supply, and the Z to another power supply alone, the strange thing is when i shut of the X and Y, the Z works perfectly, but when i turn on X, Y it makes again the same vibration, and when i reboot my machine again, the 3 motors works perfectly just for 3 minutes, after that time, the Z makes the same vibration, dont know what to do i checked and checked everything.

One thing i noticed is when i squiz a little the paralel cable, the motors all them makes a little noise as if were going to move, but i have interchanged the cables and everything and i had make L297 and L298 interchange and nothing, the same happens.

My PC is an old Pentium 200 MMX with 32 mb ram, hard disk 1 gb and win 98 SE, but is the PC??, is any interferance, what else the energ cant be becouse one power supply is only for z

I tested in an dos program "cstep" thinking on the PC and the same, dont know what to do.

Please give me any sugestion, ahh the Y card is the sync director.

Thanks

[H500]

Check your grounding. Each axis should ideally have their own power and ground pin, going to the power filter cap.

[thebackshed]

I think I have the same problem with KCam. When the machine is routing on the level, the Z axis steps one step up and down approx every half second. I have leds on the port connections, and these are also changing for the Z axis only. I think this may be a software problem in KCam.

Glenn

[Scramjet]

Thanks for your help, i solved it by lowering the feed rate in z step and checked the ground connections, one of them, in a capacitor was weak i reinforced with new capacitors and new welding, and it helpéd, no vibration, only it appears when i try to level up speed in z, but z can be slow motioned, so i dont need as much speed as in x or y, i think that the problem was in the capacitors in my board, and in the kcam program running in my such old machine.

Thanks for your helping.

[Green0]

I heard that 1000mHZ is a good threshold for windows based CNC.

If you went DOS I think you would be close or within operating paramenters.