# Problem in Machining



## sarat (Jul 7, 2011)

Hi,Everybody.
I have CNC Router with stepper(85HB110) motors and YAKO2811 drivers.I am working on 3D(NC STUDIO) carving on wooden doors.Origin is shifting(moving on X(or)Y axis) while running the machine.Z-axis also goes down.Whats problem with this,how can solve?.Cables,programms and all are correct.


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## Metalhead781 (Jul 27, 2010)

It sounds like you're loosing steps. Try slowing your speeds and feeds down. One of the biggest issues with steppers, the faster you go the less torque you have. If your router is too heavy on the machine and you try and go z+ too fast you'll loose steps in that direction causing the depth issue. If you move in x and y with too much resistance it can do the same thing. 

Regards
Randy


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## sarat (Jul 7, 2011)

Thanks,Randy.
I gave X,Y feed rate 10,000mm/min and Z feed rate is 5000mm/min.What feed rate suggestible for 3D carving works.


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## Metalhead781 (Jul 27, 2010)

sarat said:


> Thanks,Randy.
> I gave X,Y feed rate 10,000mm/min and Z feed rate is 5000mm/min.What feed rate suggestible for 3D carving works.


There are way too many variables for me to figure out where you should start. If you're loosing step in all directions then try cutting your feed rates by at least 30%. Run a test file on a smaller scrap material but let it run through the whole cut file. Make sure it's something easy to check tolerances or simply recheck your zero after. Run it again slightly increasing the speeds till you reach a point you're loosing steps in your z axis (most likely the first to loose steps). Once you hit that limit, reduce your speed by at least 10% across the board. The biggest thing to consider in this situation is the fact that your z axis is loosing steps when raising up. You need to figure out the chiploads of your bits, cutting force and machine limits. Keep a notebook handy with references to which bits you're using at what speeds in what material. This way when you come back to a similar project in the future, you'll know what you need to do.

Regards
Randy


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