Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan 
<stefan_trethan@g...> wrote:
> hi Dave!
> 
> thick wall.. yes maybe, i will check.
> i tried to flex a 4 meter piece, it is sturdy enough on 1 meter 
length for 
> anything i can imagine.
> 
> NO i want not to use aluminium.
> i don't have it and don't want it.
> i think if i want to make a mill which can also mill aluminium it 
has to be 
> steel.
> that's my opinion, i know this is wrong in principle but i want it 
so.
> ( ;-) this is the advantage of building it from scratch)


I like aluminum for small work, but for a milling machine,  I think 
it is too soft.

It sounds like you want more than just a simple PCB Router, and if 
that is the case, check out the group
http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/

please read the description on the home page.  The moderators do not 
kid around, no off topic stuff.

I think this is going off topic too far, and home this post will be 
acceptable as it does apply to small units for PCB making.


if you weld steel, it will warp and twist.  if you machine steel that 
has internal pressures, like cold rolled steel or welded steel, it 
will move when you remove metal from other places as you are changing 
the internal pressures.

making a steel table is great, but for really serious work, get it 
heat threated, yup, the whole welded table.

then level as best you can.  you don't need a table to put it on, a 
concrete floor or wood blocks that will not move would work, but I 
would assume one would make the table with legs.

also, a machinests level can be made by a flat, ground base and 
putting a thin glass tube on it filled with water.  if you use small 
glass tubing, you can clamp it on the ends and put a feeler gague in 
the center to make a very accurate and sensitive level.

Dave