Homebrew PCBs

Hi,
   Don't get confused. The milling bit only makes a tiny starting
hole in each pad. A mechanical etching bit is tiny on the end. Some
people put a tiny circle in their drawings. This lets the acid create
a starting hole for the drill. I used the same concept in my DXF file.
The depth of the starting hole is only as deep as you mill the board.
   I then drill my board with a N0.60 bit. I know this is a little
large but I have found this lets me put in all my parts with one
size hole.

                                             John  
   
                                            



--- In Homebrew_PCBs@y..., "marble_h" <marble_h@y...> wrote:
> What is the most common size dill bit used in PCB work ?
> 
> John I noticed that in your G-code that you used the same size bit 
> for both millimg and drilling  what size was it .I was thinking of 
> useing a 1/16 bit but the machine I can use has a 3/32 as the 
> smallest right now . I think that is way to big .I was thinking of 
> useing a #55 dill size for the paths ( 1/16 is bigger I know ) and 
> #60 for the mount points these may be to small any thoughts (John)
> (Group)
> 
> What is the best to use   By the way I am makeing the 3amp driver 
> from Steve Blackmore on his site . I have almost completed the 
files 
> meeded to make the G-code . Now I know why G-code is so protected 
if 
> you make one up .
> 
> John Brauweiler