[Allan Adler]

I was looking through Al Williams' TAB book on making your own printed
circuit boards this evening in a bookstore. One of its features is
a CD containing some free CAD software from SoftCad, which allegedly
runs under Windows and Linux. I don't know whether it would run on
my particular machine which has RedHat 7.1. I went to www.softcad.com
and tried to find a downloadable version of the software to look it over
and wasn't successful. There does seem to be a demo for download but, if
I understand the page correctly, it only works for one month. So now I'm
wondering whether the stuff on the CD is just the demo and will expire if
you don't purchase the real version.

Another thing I noticed in the book was the way Williams advises one to use
a laser printer. He says that you can print onto paper, as usual, or onto
transparency (possibly better), and then use an iron to transfer the
artwork to the copper clad board. According to Williams, the toner is
just a kind of plastic and it will melt if you apply an iron to it
and thereby transfer the artwork. He says one has to experiment to
get it right, since paper and printers and irons vary, and he advises
against using steam irons, even if the steam feature is turned off.

Has anyone here actually done this?

 

[Christoph Loew]

I was looking through Al Williams' TAB book on making your own printed
circuit boards this evening in a bookstore. One of its features is
a CD containing some free CAD software from SoftCad, which allegedly
runs under Windows and Linux. I don't know whether it would run on
my particular machine which has RedHat 7.1. I went to www.softcad.com
and tried to find a downloadable version of the software to look it over
and wasn't successful.

Are you *sure* it was 'SoftCAD' and not 'CADSoft' ?

http://www.cadsoftusa.com/

They produce the 'EAGLE' PCB CAD software which is free for 100mm x 80mm
PCB size, 2 layers and one page of schematics.

I've run EAGLE on Windows (ME; XP SP1 and SP2) and Linux (Red Hat 9 and
Fedora Core 2) and it runs very stable; I can recommend it.


Chris

 

[Skyscraper System Administrator]

I was looking through Al Williams' TAB book on making your own printed
circuit boards this evening in a bookstore. One of its features is
a CD containing some free CAD software from SoftCad, which allegedly
runs under Windows and Linux. I don't know whether it would run on
my particular machine which has RedHat 7.1. I went to www.softcad.com
and tried to find a downloadable version of the software to look it over
and wasn't successful. There does seem to be a demo for download but, if
I understand the page correctly, it only works for one month. So now I'm
wondering whether the stuff on the CD is just the demo and will expire if
you don't purchase the real version.

Another thing I noticed in the book was the way Williams advises one to use
a laser printer. He says that you can print onto paper, as usual, or onto
transparency (possibly better), and then use an iron to transfer the
artwork to the copper clad board. According to Williams, the toner is
just a kind of plastic and it will melt if you apply an iron to it
and thereby transfer the artwork. He says one has to experiment to
get it right, since paper and printers and irons vary, and he advises
against using steam irons, even if the steam feature is turned off.

Has anyone here actually done this?

Hi,

I can attest to the fact that CadSoft Eagle is very stable,
and all in all a great program. You'll really like it,
they're very dedicated people. If you're gonna use it I can
advise you to also immediately join their forum.

As to the making of PCB's, I just print (using an old
inkjet printer) on a transparent overhead projector sheet.

Since my old deskjet isn't very consistent in the ink
disposal, and the ink tends to be a bit too transparent in
places, I always print twice and tape the two prints
together. Try to be very precice when doing this, a good
magnifier (I use a lens from a junked photo enlarger)
is indispensable -- you'll also need it to inspect the final
product, your pcb. If there still are places that are too
light, I often even manually touch up one of the prints
with a fine ink drawing pen (0.13mm), using said magnifier
and a backlight.

To transfer the print to the photo-pcb board, I use an old
UV face tanner (4x16Watt I think). Some ballpark figures:
UV at ca. 10cm above print/pcb, 120s exposure, developing
(in FeCl) at room temp. some 15-20s; etching ... depends --
I never bring the etchant to temperature (which should be
about 50 Celsius I think), so etch at room temperature. I
just leave it in for about 45 minutes, then go back to it
and with a tweezer stir it which will result in a clean
pcb in about 10-15min. The deveoper and etchant you can in
any good electronics store, at least over here in Holland.
For the etcher I think you could also use plain sink deblocker
(caustic soda) in some dillution, but I've never tried it.

I always drill my 0.8mm holes by hand, using a common home
drill (actually it's quite a heavy type too). Microtools
are for whimps ;-)

I've designed (with Eagle, on Linux btw.), printed, echted
and soldered complete small pcb's in one day ;-)
One caveat: this can become addictive!

Good luck.

bjd
bjdouma AT xs4all DOT nl

 

[Allan Adler]

I can attest to the fact that CadSoft Eagle is very stable,
and all in all a great program.

I've downloaded it.

As to the making of PCB's, I just print (using an old
inkjet printer) on a transparent overhead projector sheet.

I know that is the usual way to do it. The point of my question is
whether anyone has tried what Al Williams said, i.e. to transfer
directly from paper or transparency to the copper clad board by
ironing the paper or transparency on the copper clad board. That
apparently causes the toner, which serves as a resist, to melt enough
to attach to the copper clad board instead of to the paper or transparency.
For this, he insists on using a laser printer.

 

[Uwe Bonnes]

: I was looking through Al Williams' TAB book on making your own printed
: circuit boards this evening in a bookstore. One of its features is
: a CD containing some free CAD software from SoftCad, which allegedly
: runs under Windows and Linux. I don't know whether it would run on
: my particular machine which has RedHat 7.1. I went to www.softcad.com

Try www.cadsoft.de

 

[Skyscraper System Administrator]

I've downloaded it.




I know that is the usual way to do it. The point of my question is
whether anyone has tried what Al Williams said, i.e. to transfer
directly from paper or transparency to the copper clad board by
ironing the paper or transparency on the copper clad board. That
apparently causes the toner, which serves as a resist, to melt enough
to attach to the copper clad board instead of to the paper or transparency.
For this, he insists on using a laser printer.

I think I've seen this method discussed on one of the Dutch
electronics forums. I have no personal experience with it,
though I'd say it might work. If I were you I'd just try
it, I mean I'd experiment with fake laser-prints and some
materials that might resemble the pcb sensitive layer, just
to see if the transfer occurs at all, and if so, at what
temperature. Then just try it on a small real pcb.
That's why I would do.

Another method is to print the pcb layout directly onto the
pcb using a flatbed plotter. I obtained two old Mural 8000
plotters (A0!, slight overkill for the pcb's I make...)
recently to exactly that end, but haven't given it a try yet
-- no pens to be found in this vicinity (meaning I'll have
to construct my own from a fine ink drawing pen, something
which I haven't come around to yet).

How do you like Eagle?

bjd

 

[Al Williams]

The software with the book is the "freeware" version of CadSoft's
Eagle CAD. It is fully free for personal use and works with boards up
to a half Eurocard in size and two sides. The software has a great
library and a pretty strong autorouter along with schematic capture.
If you want more than 2 sides or bigger boards, you do have to
upgrade, but the software is well worth the expense and many people
get along fine with the freeware version.

The PCB toner method works very well once you find the right
combination of paper, laser printer, and iron that works for you. One
thing to note is that you don't iron the pattern onto photoresist. You
actually put it on the bare copper and the toner IS the resist.

As someone else said earlier, get a blank copper board and an iron and
experiment. When it doesn't work, you can always strip the board back
down with acetone and try again.

The book covers this method in detail along with photo methods. It
also covers how to use Eagle (including things like building custom
components and sending CAM files out for production).


Regards,

Al Williams
http://www.awce.com

 

[Allan Adler]

electronics forums. I have no personal experience with it,
though I'd say it might work. If I were you I'd just try
it, I mean I'd experiment with fake laser-prints and some
materials that might resemble the pcb sensitive layer, just
to see if the transfer occurs at all, and if so, at what
temperature. Then just try it on a small real pcb.

I've walked around in wrinkled clothes my entire adult life because
I don't own an iron. I have a Canon BC02 Bubble Jet printer and no
laser printer. So it will involve some commitment of resources to
simply try it. Before doing that, I just wanted to know whether anyone
else had any experiences to report, other than the author. (Thanks to
Al Williams for adding his helpful comments to this discussion. I don't
doubt what he says, I just wanted other points of view.).

Anyway, I guess there is no alternative to trying it. I can try to get
an (non-steam) iron, take scrap paper from someone else's laser printer
and see if I can do any transfers.

I have very little discretionary capital, so I like to check things out
carefully before I commit any resources. For example, that is why I merely
looked through Al Williams' book in the bookstore instead of buying it,
even though it looked interesting and even though, as books go, it is
pretty reasonably priced. I know how badly wrong one can go by throwing
money at a problem instead of investing thought in it.

Regarding Eagle, although I downloaded it, I haven't had time to experiment
with it. I've been giving priority to my unfunded mathematical activities
and they have been fairly intense lately.

 

[Allan Adler]

They make a blue sheet that you print it on then iron on to the copper
baord before etching, works pretty good. Don't know about a direct
transfer...

Who are "they"? Is the blue sheet different from ordinary transparency?

 

[Allan Adler]

Both DynaArt designs (now called pulsar) and Techniks sell special paper. And,
an earlier question on 'what kind of controlled heat source'.. The only thing
that I have come across that offers any consistency is a heat-press.

I did a google search for heat-press and came up with machines for transferring
designs to t-shirts. They don't look cheap, but I didn't see any prices. I
looked at the pulsar website and now I understand what a laminator is. They
don't seem to sell them directly, as nearly as I can tell, but say that they
usually go for $140, sometimes only $99, at places like Staples. That's good
to know if one can't get the iron to work. Thanks for the info on this
and the transfer paper.