Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

I would not buy his plans even if i could.
The hardest for me is not how to make it, but how to get the needed
material.
The plans don't do the work for me.
Making some errors during development i something i risk, but i doubt i
would be satisfied
with any plans. (you have to search for the specific parts then also...)


I think it is good possible to see from the pictures of his machines which
principles he
uses, (e.g. which rail mechanism). For someone with a bit understanding
of mechanics there are no dimensiones etc. required.


Look he too uses the ball bearing on pipes/rods...
i located a big length of stainless pipe (maybe flag pole or similar)
at a relatives shed.. have to inspect for surface quality but if it is ok i
am sure
i can get it..

another source for good rails is ebay..
at ebay.de (for markus....) there are always a lot of "linearführungen".
often ground steel profiles with ball or roller beared carriages. no play.
also acme threads with ball-beared nuts ("kugelumlaufspindel") are sold..

it is not as cheap as pipes or steel profiles but a lot more precise.


I was thinking about the cnc for some time now, not really having time to
build one
but gathering information..

i initially wanted to make a steady table with the spindle moving all three
axis..
now i think it is easier to move the workpiece the one direction (x), the
spindle y and z on a vertical mount (like seen on many designs, including
kleinbauers).
Not sure what's better...
I want to use the machine not only for pcb making (and there maybe only for
drilling)
so i have dome extra requirements.
if i make "ball bearing" slides (and not buy good oned from ebay) they need
to be steel.
a ball bearing only conacts the rail on one small point (ok a lne with a
flat rail).
if you use aluminium bearings and want to mill aluminium this may not be
sturdy enough.
ball bearing rails have the disadvantage of small contact points. (i think
because of this
on other tools like lathes/mills dovetails are preferred).

i have a lot of other ideas.. but i don't want to bore you...

feel free to discuss any part of pcb cnc mill construction (anyone..).

stefan