Homebrew PCBs

Stefan Trethan wrote:
 > interesting idea!
 > but i don't think i have rod end bearings at home.

You can buy them from bearing suppliers. When I was looking at
using rod ends for this project a few years ago I remember them
being not expensive. I will one day redo my drill machine so its 
more compact and lighter.

  > do you think there is no clearance in rod end bearings when
 > they are new for horizontal movement?
  >

Rod ends are just a plain spherical bearing inside a housing
designed go on the end of a rod, I wouldn't expect any noticeable
play. I haven't seen them myself, but I've been told there isn't
any play you can feel.

here is a picture.
http://www.qbcbearings.com/RFQ/B610HTML/B610P161.html

 > i can buy the proxxon drill at a mail order company but so i 
can't get my hands on it prior to buying to
 > inspect it closely.
 >

Its difficult to know the quality without looking at one and 
testing it. Maybe you can contact proxxon and find out more 
detailed specifications of the drill.

 >
 > as you see i won't start building before i don't have a 
suitable drill.
 >

yes, I would do the same. The mount for the dill may not be easy 
to make without the right tools.