Homebrew PCBs

Sorry as I posted to the list owner instead to the
list recipients.

The former messsage was as follows:

--- teknochaman <teknochaman@...> wrote:
> 
> > Hi All,
> > 
> > This is my first post here.
> > 
> > I'm newbie to PCBs but familiar with
> > > positive/negative
> > graphic film (former printshop manager)
> > 
> > Wanting to do home etching it's an intuitive
> 'upgrade
> > ' of my skills.
> > 
> > I'll use presensitized positive boards (epoxy
> > substrate) and I wonder where to go for knowing
> about
> > track thickness issues in terms of current passing
> > thru copper tracks.
> > 
> > I'd like having more solid foundations than the
>common
> > sense i.e. with wire (roll not flat ) it's known 1
mm = 1A, 2mm = 2A , etc.

> > Any equivalence for tracks or minimum distance >
>between tracks to avoid arcing ?

 
> > BTW  I'm also a DIYer of small microelectronics
> > projects. 
> > 
> > Being baby boomer hope some day having enough time
> to
> > build my own CNC based cutter (some day) one as
seen on today
> > posting.
> > 
> > For sure as an old eBAYer I assume that parts can
> be
> > found at the auction hub for the world.
> > 
> > TIPS are welcome.
> > 
> > Anybody is welcome to send me beginner's tip here
> or
> > in private to avoid disturbing with too obvious
> > matters regarding current postings.
> > 
> > Hope get here motivational resources which IMO is
> as
> > important as the knowledge in itself.
> > 
> > 
> > To fulfill forum requirements
> > (and to demonstrate that I'm a human
> > being rather than a bot) :)
> > 
> > 
> > My goals:
> > 
> > 1. To build a integrated light-timer to avoid
> doing it
> > manually (i.e. thru a 555 or the likes integrated
> > circuits)
> >  
> > 2. To upgrade my UV light source with a more
> powerful
> > metal-halide type to reduce exposing time
> > 
> > 3. If it should be of help I'd adapt my vacuum
> frame
> > it shou(for offset plates burning) to put there
> also ,
> > the film pressed against the copper substrate base
> if
> > that should help.
> >  
> > 
> > 
> > .SCH file extension 
> > question
> > *******************
> > 
> > I've seen at many DIY sites that PCB software is
> used
> > from a site of free download (.sch extension).
> > 
> > I'd say that at a first look expressPCB would be a
> > free software for layout, but seems to be
> propietary
> > software in terms of they expect people sending
> them
> > their files for production purposes.
> > 
> > Those .SCH files using that software (many
> published
> > at .DIY sites) can be routed to an ordinary
> printer ?
> >  
> > Let's say to get printouts ready to be put i.e. ,
> on a
> > polyester film  ?
> > 
> > I 've heard about Gerber, Tango (Protel), Eagle,
etc. files
> but
> > not of this so called "free" but orientated to be
> tied
> > a commercial purpose ., as it would be ordering
> PCBs
> > which is in fact the OPPOSITE to this forum goal,
> > where we intend to homebrew our own PCBs.
> > 
> > Bests, peace for all this Season and TIA
> > 
> > Samuel J.


P.S.

Sorry it's long, but think being my first post here
I'll get mercy !

a longer 

__________________________________________________
Correo Yahoo!
Espacio para todos tus mensajes, antivirus y antispam \ufffdgratis! 
\ufffdAbr\ufffd tu cuenta ya! - http://correo.yahoo.com.ar

First, some here have much more experience but out of all the years and all the methods I've tried, positive/Photo is my favorite.  Nice, quick, easy, and accurate.

I've tried several brands, but my favorite was always MG Chemical boards.  They are more expensive and getting a little harder to find, but I had no problems with very fine traces.  I use their developer when possible and never had any throw aways.  I can't say that for some of the other brands I used.  I'm open to opinions though.

My Frame is nothing more than a small stool like table, with an upright on it for my lamp to hold it centered over the table.  It has a smooth bottom and I position my board,  layon the transparency  (HP LaserJet) and set a section of 1/8" thick glass on it.

To expose, I use a 250 watt, reflector Infared heat lamp, spaced at 11" from the board, for 70 seconds and they come out perfect EVERY TIME.

I tried the toner transfer and had absolutey no success.  I tried the expensive transfer paper with mixed results.  I tried some of the cheaper no name positive boards with "OK" results, but none compared to the MG.

Etching Tank, mine is 12" vertical, 12" wide, and about 1-1/2" thick.  I use an aquarium heater and an Aquaruim air pump and it does good.  I think I bought it somewhere like Jameco for 40 or 50 bucks.

CAD software, well, I'm not successful with that yet.  I got real good with Windraft and WinBoard from Ivex but they went out of business.  I know have to learn Eagle, but their constraints on PCB Size is a joke.  


You should get a lot of responses with many different and plausable ideas.

Have fun,
RIchard



[Non-text portions of this message have been removed]

"Richard" <rwskinner@...> writes:
> CAD software, well, I'm not successful with that yet.  I got real
> good with Windraft and WinBoard from Ivex but they went out of
> business.  I know have to learn Eagle, but their constraints on PCB
> Size is a joke.

Tooting my own horn here, but... have you tried gEDA and PCB?  They
are free (beer and speech) and have no intrinsic limits.  I once
calculated that the largest board PCB could support was a quarter mile
square, at 0.01 mil resolution (although 32"x32" is a more "stable"
limit, for historical reasons).  It also supports an essentially
unlimited number of copper layers (the default build is 8 active
layers out of 16 max, but you can easily compile it for more).

The development group is fairly active at the moment, too.

--- In Homebrew_PCBs@yahoogroups.com, "Richard" <rwskinner@...> wrote:
>
> CAD software, well, I'm not successful with that yet.
> I got real good with Windraft and WinBoard from Ivex
> but they went out of business.  I know have to learn Eagle,
> but their constraints on PCB Size is a joke.  

You might want to look into KiCAD:

  <http://kicad.sourceforge.net/>

It is cross platform -- WinOs, MacOS, Linux, etc.
KiCAD has no board size restrictions.

-Wayne

Has anyone recompiled PCB for windows (or cygwin, for that matter)?

I can deal with small micros (like PICs), but I wouldn't know where to 
start with a project like compiling PCB under Cygwin.

CW

>
>
> Tooting my own horn here, but... have you tried gEDA and PCB? They
> are free (beer and speech) and have no intrinsic limits. I once
> calculated that the largest board PCB could support was a quarter mile
> square, at 0.01 mil resolution (although 32"x32" is a more "stable"
> limit, for historical reasons). It also supports an essentially
> unlimited number of copper layers (the default build is 8 active
> layers out of 16 max, but you can easily compile it for more).
>
> The development group is fairly active at the moment, too.
>
>