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Subject: Re: Parser for RS-274X header.

From: Alan Marconett KM6VV <KM6VV@...>
Date: 2002-04-26

Hi Hans,

Yeah, I downloaded PCB editor, and looked at the board with it. I was
seeing the silk layer, as well as solder mask, I think. One layer was
solid! Perhaps there are duplicates of layers. Several seemed to have
pads and traces, more then two. But then, I cut and pasted out of the
97K file, to get each marked "layer" as a separate file (that's all my
program can handle). Perhaps some should have been combined.

I think the reason the mill bits wear out so quickly is that they are
cutting the glass-epoxy board. The copper probably isn't the problem!
I'm tempted to try just cutting a "resist" layer, and etching the final
(something I think John suggested). But I've got plenty to do before
then!

I've etched some small boards, many years ago, I'm just fixated on CNC
and milling a board! I can remember my first mouse and graphics board
(CGA). The first thing I wanted to do (did) was write a PCB layout
program! I think that first Logitec mouse and PC Paint program cost me
$300! For a IBM PC (before even the XT's).

The Eagle files would be nice. I'll check out the new release!

Alan KM6VV


hans@... wrote:
>
> Alan,
> The Gerber files include "empty" layers. The Modular design is a two
> sided PCB, simply discard the empty layers.
> BTW I do not mill boards it's far too mauch work, I use Pre Sensitized
> stock and exposure for 120 second using a GE 500W bulb,
> then developing in a solution of Red Devil Lye, etch with Ferric
> Chloride, the same Ferric Chloride I have been suing for 8 years !, most
> people do not understand it, and they throw it away far too soon. Heck I
> even use the same Red Devil Lye mixture until it's so green I can hardly
> see the PCB developing.
> .... I can make a two side board (without drilling) in about 45
> minutes... 5 mill traces at 8 mill spacing are normal.
> BTW mill bits, I wonder why mill bits wear out so quickly, after all
> it's only copper! Could it be because people run the bit dry ? May be
> people are not buying real mill bits...
> I have a link at my site for a source of really good quality mill bits,
> size down to 0.002" ( yes! 2 mil ) But 2 mil bits are not that cheap....
>
> hansw
>
> Alan Marconett KM6VV wrote:
>
> > Hi Hans,
> >
> > That's quite a nice project! I think I counted 8 layers in one of the
> >
> > GBR files! And with over 20 apertures, I'll have to get a parser for
> > the header working! I think I can pick a layer or two with pads and
> > traces, and manually build an aperture table for some simple tests
> > with
> > my code. I was able to see a lot of the "foil" layers by using some
> > aperture sizes I had defined previously for another (Eagle) demo
> > board.
> >
> > Thanks for the URL!
> >
> > Alan KM6VV
> >
> >
> > hans@... wrote:
> > >
> > > crankorgan wrote:
> > >
> > > > What I find is people are unable to find anything on
> > > > the internet. Maybe they use the wrong search engine.
> > >
> > > I posted a complete design with PCB layout files and schematics at
> > my
> > > web site, during
> > > the past years I have received 100's or emails from people that have
> >
> > > successfully built the
> > > Modular Design, with or without the "Smart Current Monitor".
> > >
> > > The design is Free... I do not charge anything for it..
> > >
> > > When I get time I'm going to post a new design complete with EAGLE
> > > files...
> > >
> > > Hans W
> > > http://hans-w.com