Homebrew PCBs

I'm curious why there is so much interest in hobbyists who make no more 
than couple of PCBs per week would need a CNC drilling machine to drill 
the holes. I found hand drilling is not that big a deal when you have a 
good drill press. There is a prototype place near my area and I noticed 
they hand drill the holes even though they have a small CNC drilling 
machine. The owner of the shop told me by time they setup the machine 
its quicker to hand drill. So, anyone thought about building a really 
good drill press ?

The drill press I made couple of  years ago is still working very well 
and I'm happy with it. The basic design uses a straight grinder mounted 
to the end of a long arm (400mm) which pivots at the opposite end. This 
is mounted on a wooden base.


             ___
             | |
  o__________|_|  straight grinder
  |           |  
 _|____________________   wooden base (18 mm MDF)


The arm is made from a piece of 50 x 50 mm aluminum square. The pivot is 
made from two thrust bearings (from car clutch) that clamp on opposite 
sides of the square aluminum arm. This is then fixed to the wooden base 
with two pieces of aluminum right angles. In the diagram, thrust 
bearings are "2", the arm is "3". Threaded bar, "4", goes through the 
right angles , the thrust bearings and square arm so everything is 
tightly clamped.


          _    ____    _
         | || |    | || |
    4=== | |2 | 3  | 2| | ===4
         | || |____| || |
   |-----  |          |  -----|
-----------------------------------
-----------------------------------    <-- wooden base


This setup gives stable and extremely smooth vertical movement of the 
drill. There is of course an inherent arc movement of the drill bit. 
This does not cause a problem when the drilling depth is only a few 
millimeters. The most difficult part for me was mounting the straight 
grinder to the end of the arm. This fixture needs to be adjustable to 
allow slight alignment of the drill so it has perfect vertical feed. I 
choose a straight grinder (BOSCH GGS27) because it was the only thing 
around that came with a precision hardened steel ground collet and also 
in my price range. The roundout is acceptable for carbide bits, (haven't 
broken my 0.45 mm bit yet). The Dremel I first tried was useless because 
of the sever round out. Luckily I got my money back. Major problem with 
this machine is it can take up a bit of space. It compromises low 
complexity for size. One improvement to the design would be to add a 
stepper motor control for the down feed. That way both hands can be used 
to position the PCB and a food pedal to operate the drill feed. Any 
thoughts ?