Homebrew PCBs

for what do you want your cnc machine?

if you want it only for drilling pcbs it can be less precise and mechanical 
stiff.
(drilling only needs vertical force).
some here (ncluding me) feel confident this can be made with simple and 
cheap "drawer slides" as rails
and stepper motors.

if you want to mill your boards (isolation milling) then you need a more 
stable machine.
when milling there are forces is all directions and it must be really 
precise.

i have seen some mills which use some sort of steel rails and 3 or more 
ball bearings (on each
bearing point) which roll on the rails. for driving the carriages i nearly 
only have seen allthreads.
(are there any timing belt machines out there). threaded rod and direct 
stepper motor drive works
if you somehow eliminate the play on metric (or other) threaded rods (two 
nuts counterloaded or split nut).


as spindle (this is the "power drill" which holds the bit)
you need a unit which has substantial bearings (for millig because of side 
force).
dremel has been used but shown often to be too flimsy. i suggest a proxxon 
ib/e or better.


but i would suggest to stay with chemical process.
i think it is possible with much less cost and work to get perfect boards 
made.
milling has some disadvantages.


please describe your problems with double sided boards more precise.
please tell us which chemicals/material you already have, there are a 
number
of ways to sucess and not only one special way.

(please also don't use "help me please" as subject, read the groups 
guideline)

please state the quantity of boards you need to make (also in the future).
further the quality (min track with) and if throughhole plated is required.


tell us which printer you have, if you already are able to make films.

also if you have acces to precoated pcb material, or liquid photoresist, or 
dry film (for lamination).

are your problems about aligning of the boards? what did you try until now?
don't be afraid to keep us reading some minutes with 2 written pages, the 
more we know
the better we can help and the faster you have perfect boards.

which etchant did you try?

you must understand, it is impossible to help you without telling us more 
details.

regards
stefan




On Fri, 03 Oct 2003 07:24:29 -0000, Juan 30.SA.146 // EA7??? 
<esp7xx@...> wrote:

> I'm so interested in make a homebrew CNC machine. Does anybody know any 
> webpage to get plans and instructions to make one?
> Thanks for help me.
>
>