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

previous by date index next by date
previous in topic topic list next in topic

Subject: RE : [Homebrew_PCBs] Milling circuit boards with CNC?

From: Robert Hedan <robert.hedan@...>
Date: 2005-06-11

We're still here; either waiting for another member to move along on his
driver design, waiting on parts or workin on the structure for the most
part.

In the meantime, I'm stocking parts in 2 versions: lightweight material for
the drilling station, and heavy-duty for the CNC machine.

Just got my hands on 3/4" 10TPI long screws today for the CNC, and I have my
eye on 3/4" pillow blocks (more to come on that). I'm also waiting for 20mm
precision rods and linear bearings to come in as well. I'm most likely
going to be using 3/8" 16TPI screws for the drill with polished 1/2"
aluminium rods (quick and dirt). I'll probably fabricate teflon or plastic
bushings to slide on the rods.


V outlining VS flat milling all copper:

- I see nothing wrong with leaving 'all that copper', I use it as my
negative and helps to reduce noise (<--- total newb here, so please feel
free to add on this). Leaving it on also helps keep the etchant clean and
takes less time to machine.

My intention is to use the drilling station for V-scoring and drilling PCBs
as well as drilling faceplates. As already mentionned, we already have all
the coordinates for the holes in the DRILL file.

I did think of another feature I will include on my drilling station; a
small camera for quality control. I already have 2 cams ready to connect on
a PCI card. I will be able to switch Windows to supervise the work from my
PC and check the quality of the work in progress. Check EBay for small
cameras. Don't bother with wireless and you'll get them dirt cheap.

The last thing I'm still researching is how to process track pins on the
drilling station (plugging vias).

Robert
:)



-----Message d'origine-----
De : Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] De
la part de lcdpublishing
Envoyé : juin 10 2005 10:09
À : Homebrew_PCBs@yahoogroups.com
Objet : [Homebrew_PCBs] Milling circuit boards with CNC?


When milling a circuit board on a CNC, I can see two possible
approaches...

1) Using a 'V' shaped bit to outline the traces. This leaves a lot
of the copper on the board.

2) Using a flat bottom milling cutter and cut away all of the unused
copper.

As I have never done this before, is one method preferrred over the
other, or perhaps even another way of doing it?


Chris

Also, what happended to all the discussion on building a CNC machine
for this purpose? There was a bunch of talk, then it all seemed to
dissappear - did it get moved to a different group?








Be sure to visit the group home and check for new Links, Files, and Photos:
http://groups.yahoo.com/group/Homebrew_PCBs

If Files or Photos are running short of space, post them here:
http://groups.yahoo.com/group/Homebrew_PCBs_Archives/
Yahoo! Groups Links