Homebrew PCBs

gettingalongwouldbenice wrote:

> positions to align the board.  But it was tedious going back and forth.
> It should be a simple matter to do the rotation math to just calibrate
> the drill to any board rotation.  Started down that path, but lost


   The rotation math really isn't that bad, after aligning manually to two holes 
in opposite corners, but there are many ways to skin the cat.

   Reference line marked or scored with a tool on the backing.  Drill two holes 
on a line and sight the reference.  Once you're rectilinear offsets are easy. 
And skip those first two holes, just put a ruler across the holes and mark at 
the edges of the board, align to the reference line and it's square to the grid. 
  Bring a bit near the board, get it over a known hole, do the 90 degree cross 
check and set the coordinates for that hole.  Then go.  Really best to have 2 
lines at 90 degrees, use a corner hole and two out at the other corners.  That 
way you know you're fully aligned all the way across the board.

   So the math's easy enough, but very little reason to do it when mechanical 
alignment is easy too.  I've never bothered to put it in my driller for that 
reason..

Alan