Hello All,
I have just joined the forum, and briefly read over some posts that sound similar to this one. However I have a bit of a different situtation and would like some advice if possible.
I am currently a student taking electronics engineering, and for a design project would like to build a milling machine. The electronics involved I will be able to design and build myself, so as far as stepper controllers go, I should be able to take care of it.
So the hard part is fast becomming what to use to build a CNC machine. It seems that assembling the machine is not that difficult provided you have some basic welding and fabricating skills, but finding the right parts is a challenge.
The primary use for the machine will be to machine wood and aluminum. But I would like to also machine steel. I notice that machining steel requires alot more design consideration. This is probably an unrealistic goal, but I would also like to mill pcb's. So it will have to be accurate, strong, and durable.
The desired cost for the project is, as cheap as possible. Hopefully between 1000 and 5000 dollars. So for now any ideas or requirements that the experienced people here have, just throw an estimated cost.
For the motion control I want to use a ACME leadscrew, since ballscrews are exponentially more expensive. The nuts used will be a higher quality anti-backlash type, to try and squeeze a little accuracy out of it. Would this setup be adequate for milling steel, and what kind of precision would it provide practically? Would it be adequate for milling pcb's, would it be adequate for milling pcb's that dont have ultra fine trace spacings?
How much oz-in of torque do I need to get for the stepper motors? I was going to use linear bearings running on a linear shaft that is end supported. But I am pretty sure that its going to have to be supported by a rail as well? As far as the frame of the machine goes, I have alot of scrap steel that can be thrown into it to make it massive and strong.
The style that I want to build is the overhead type.
So if anyone here has some insight as to the requirements for the different parts (ie lead screw/ ball screw, diameter of screw, diameter of linear rails, bearing requirements, stepper motor oz-in requirements) I would really appreciate the information before I buy components that are useless.
For this project plan B is to be able to just mill aluminum and pcbs, and plan C is to cast aluminum parts instead of milling them.  |