I am looking at buying a cnc router to prototype my circuits to eliminate issues that arise from dodgy connections on my breadboard.

Ive gome through tutorials that use a cad software to generatr the gerber files, copper cam to generate the instructions to the cnc and mach3 to control the cnc machine.

Im now at the point wherr i can do this with the exception of the bits to use.

Some use conical or tapered tools, others use pcb end mills. Some use a variety of drill bits whereas others get away with using 2.

Has anyone figured a general solution for bits. Ie use this for isolating paths and 2 drill bits where one will be used to bore larger holes?

 

Really all depends on YOUR needs..
If your machine does not have auto tool changes then its easier to just use one drill bit size and one "V" bit for isolation routing and run 2 programs..

On boards I might prototype I would need small holes for smaller through hole pins and some larger holes for larger pins..
But if all your components are (for example) .030 leads then one drill is sufficient..

carbide tooling is best as PCB laminates are pretty abrasive and will wear normal high speed tooling pretty darn quick..

 

carbide tooling is best as PCB laminates are pretty abrasive and will wear normal high speed tooling pretty darn quick..

Though, for hobby use, it is worth getting FR2 boards which are available in single- or double-sided. They are much more gentle on the tools and the dust isn't as bad for you as FR4 (glass-fibre).

I use a 0.3mm end mill which can make gaps and tracks of 0.3mm which is good enough to put a track between the pins of a DIP IC.

 

Have you checked out the Chinese board suppliers?
The likes of Seeed etc have current offers of $5.00/10 boards 100mmx100mm.
It may make more sense than the investment in CNC.
Max.

 

Yeah I just get all my proto boards from itead PCB..
In about 2.5 weeks I have "professional" boards here complete with plated through holes/silkscreen/solder mask,etc..
Quality is top notch so far for me.. (about 10 or so orders of all different shapes/sizes.. most 2 layer but have done 1 4 layer too through them)

 

The likes of Seeed etc have current offers of $5.00/10 boards 100mmx100mm.

Plus postage?
Plus delivery time?

 

Plus postage?
Plus delivery time?

If you can live with a bit of delay as opposed to the investment in a CNC with the attendant real estate it takes and time taken to produce a board and end up with no plated through holes or silk screen etc as @mcgiver noted.
Max.

 

There's no silk screen, however the CNC can etch text onto the board. I use rivets for vias which are easy an quick to use. The CNC can also etch text and graphics onto panels, make neat accurate holes for connectors and displays and make specially shaped mechanical parts - motor mount, lens mount, levers, buttons, etc.

At the moment I am using mine to make a wooden clock like this: