A 6 DOF robotic arm as a CNC machine?

Hi,

I have always dreamed of cheap 5 axle CNC machining mill. It should be possible to CNC-machine a car with that or similar complex object like a human head.

Once I am good to make excellent modelings with Rhinoceros I would like realize these modelings too in real life.

But is there any sense to buy a low cost 6 DOF robotic arm from ebay and use it as a tool like this:

http://www.ebay.com/itm/New-6-DOF-Manipulator-Aluminum-Robot-Arm-Kits-for-Smart-Car-Base-/160998716216?pt=LH_DefaultDomain_0&hash=item257c457338

Is it really difficult to program arduino make whatever form from .stl files in order to CNC machine them with this kind of robotic arm?

Maybe the table where the machinable object is fixed could have such an function that it could rotate with a servo. But I think that in theory a robotic arm with a

table like this should be able to machine whatever form.

Please tell me your opinions of a plan like this. Many thanks in advance.

I found a machining open source software like this for Linux...

It probably helps in this issue.

But is there any sense to buy a low cost 6 DOF robotic arm from ebay and use it as a tool like this:

No.

Not enough:

accuracy
torque
range

with that price point.

You could probably do it for around ~$15,000+, looking at the prices of appropriate DOF welding robots on ebay.

"Not enough:accuracy,torque,range"

HI
All i need is exactlly that cheap a$$ robot arm with low accuracy with a small motor with 1 foot range

as RaiRaiRai asked a while ago
"Is it really difficult to program arduino make whatever form from .stl files in order to CNC machine them with this kind of robotic arm?"

please advise & help

All i need is exactlly that cheap a$$ robot arm with low accuracy with a small motor with 1 foot range

Then go for it.

as RaiRaiRai asked a while ago
"Is it really difficult to program arduino make whatever form from .stl files in order to CNC machine them with this kind of robotic arm?"

Do you know what an stl file looks like? It's a collection of triangles, each of which has a normal. What, exactly, would you want to do with it?

You could import an stl file into a CAM system, and generate tool paths, and export that data as M and G codes, and then write a program to send those codes to the Arduino.

However, the Arduino makes a pretty lousy reverse kinematics solver, so it will take a while to get the necessary joint angles to move the servos to, to get the end-effector in the proper place/orientation.