Homebrew PCBs

> Hello Group
>
> I have a quick question about precision drilling of home made PCBs.
>
> Because of poor eyesight, I use a CCD microscope next to my Dremel
> Model 300 drill press stand.  Although this set up is a big improvement
> over doing thing solely 'by eye', there is a parallax error introduced
> between the location of the retracted drill tip and where it eventually comes in contact with the PCB.  Once I saw a milling machine where one
> was able to sight straight down into a bulls eye.  Is there a way to 
> rig mirrors to do this?  
>
> P.S. Sincle sided boards are no problem, as I can hold them up to
> strong light and position a hand held rotary tool with good enough 
> accuracy.  
>
> Any suggestions would be appreciated.
>
> Cheers
>
> Chris
>   
Hi Chris,

You might try to find a metallic  first surface mirror that you can 
drill a small hole into on a 45 degree angle
and mount onto your drill stand with the drill bit going through the 
hole. Position the camera so it looks into
the mirror from the side and down the drill via the mirror.

A less elegant method is to use two point source lights (small halogen 
desk lamps) mounted 90 degrees apart
and pointed toward the drill tip. As the drill tip approaches the board, 
the shadows will converge on the target.

Bruce