Bought this kit at Radio shack, its copper plates, a sharpie marker, and
solvent. You draw your circuit with the marker and dissolve everything with
the acid. Is there anything wrong with these things for pro use?

BlacklineMusic wrote:
Bought this kit at Radio shack, its copper plates, a sharpie marker, and
solvent. You draw your circuit with the marker and dissolve everything with
the acid. Is there anything wrong with these things for pro use?

Not really, but it's a bloody pain in the neck to do them by hand that way,
and you can only make one at a time since your original layout is destroyed
in the process.

You'll get a better result if you use line tape as much as possible, and
use the resist pen only for the smaller parts.

Given how cheap expresspcb.com is, I have pretty much stopped doing boards
by hand at home.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

In rec.audio.pro, (Scott Dorsey) wrote:

BlacklineMusic wrote:
Bought this kit at Radio shack, its copper plates, a sharpie marker, and
solvent. You draw your circuit with the marker and dissolve everything with
the acid. Is there anything wrong with these things for pro use?

Not really, but it's a bloody pain in the neck to do them by hand that way,
and you can only make one at a time since your original layout is destroyed
in the process.

You'll get a better result if you use line tape as much as possible, and
use the resist pen only for the smaller parts.

Given how cheap expresspcb.com is, I have pretty much stopped doing boards
by hand at home.

I've used that too, but it appears there are many who want to make
their own boards. There's a current thread on sci.electronic.design
with the subject "printed circuit boards" discussing just this topic,
and they've discussed it on the tech-talk forum on recording.org.

--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

-----
http://mindspring.com/~benbradley

Scott Dorsey wrote:

BlacklineMusic wrote:
Bought this kit at Radio shack, its copper plates, a sharpie marker, and
solvent. You draw your circuit with the marker and dissolve everything with
the acid. Is there anything wrong with these things for pro use?

Not really, but it's a bloody pain in the neck to do them by hand that way,
and you can only make one at a time since your original layout is destroyed
in the process.

You'll get a better result if you use line tape as much as possible, and
use the resist pen only for the smaller parts.


For a while I used the same screenprinting set-up I had for CDRs to
apply the layout to circuitboards. The nice thing about the etchant is
that just about anything will work as an etch resist: Sharpie, wax,
lacquer, tape, probably even grease. But it's still a massive pain in
the ass, and once you get a good pattern applied and etch it
successfully, you still have to drill holes in it. Some people
successfully etch double-sides boards but I would rather eat glass than
hassle with that.


Given how cheap expresspcb.com is, I have pretty much stopped doing boards
by hand at home.


Spezackly.

ulysses

Justin Ulysses Morse wrote:

For a while I used the same screenprinting set-up I had for CDRs to
apply the layout to circuitboards. The nice thing about the etchant is
that just about anything will work as an etch resist: Sharpie, wax,
lacquer, tape, probably even grease. But it's still a massive pain in
the ass, and once you get a good pattern applied and etch it
successfully, you still have to drill holes in it. Some people
successfully etch double-sides boards but I would rather eat glass than
hassle with that.

I always liked the positive resist material. Do your layout, xerox it
onto a transparency, then put it in the sun with the positive resist
and you have a nice image on the board. I used to do a lot of double
sided boards at home this way. I once made a bunch of phono preamps
with the positive resist stuff on the stove in the kitchen of my college
dorm and got a nasty letter from the school Housing department.

There is new material that can be run directly through xerox machines or
laser printers, then the toner image transferred onto a PC board with
a steam iron. This wasn't out when I was in the dorms, but I know folks
who have got very good results with it.

I tend to use perfboard for the first design, then expresspcb for the next
couple variants.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

There is new material that can be run directly through xerox machines or
laser printers, then the toner image transferred onto a PC board with
a steam iron. This wasn't out when I was in the dorms, but I know folks
who have got very good results with it.

I tried it, and my results were godawful. It only partially transferred. Tried
several times with varying iron temperatures, etc., and it sucked every time.
Maybe I was doing something wrong, or maybe my xerox machine was bad, but I
never got a usable board in half a dozen tries, so I quit.

Peace,
Paul

On 13 Sep 2003 06:06:10 GMT, (P Stamler) wrote:

There is new material that can be run directly through xerox machines or
laser printers, then the toner image transferred onto a PC board with
a steam iron. This wasn't out when I was in the dorms, but I know folks
who have got very good results with it.

I tried it, and my results were godawful. It only partially transferred. Tried
several times with varying iron temperatures, etc., and it sucked every time.
Maybe I was doing something wrong, or maybe my xerox machine was bad, but I
never got a usable board in half a dozen tries, so I quit.

Peace,
Paul

It took me over a half dozen tries to get it right. The circuit board
must be pristine clean for the toner to stick. This meant scrubbing it
down with a scotchbrite pad or emery cloth then wiping it down with
lacquer thinner or alcohol. No finger prints on the board allowed!
Even after I got one right, the next was a couple of retries before it
worked.

The best results are obtained by a photo resist method. I have
produced professional quality(single sided) boards with this method.

Ed

P Stamler wrote:

There is new material that can be run directly through xerox machines or
laser printers, then the toner image transferred onto a PC board with
a steam iron. This wasn't out when I was in the dorms, but I know folks
who have got very good results with it.

I tried it, and my results were godawful. It only partially transferred.

There are at least three brands of this kind of stuff available, and they
work differently. The only one I've gotten to work fairly consistenty
without excessive hassle is the PnP Blue film. It's transparency film,
but with a blue power-like film adhered to one side. You print the
toner on that side, and when you transfer to the PCB with an iron, the
powder not only helps release the toner but also fills in the very tiny
gaps and pinholes in the toner. Like Scott I tend to outsource my
boards now (http://www.apcircuits.com/), but I've had some success with
PnP when I've tried it. It should be emphasized that a factor in favor
of using a board house is that they can deal with the chemicals in an
environmentally sound way a lot more easily than most of us can.

Here's a source for PnP blue:

http://www.techniks.com/

The trickiest part of the process is using an iron to transfer the
toner. Techniks sells a press for about $300 that supposedly improves
this process, if you plan to do this a lot. Dyna Art (now Pulsar) sold
a modified laminator to accomplish the same thing for some time, but
I wasn't able to find it at their current site:

http://www.dynaart.com/

Their toner transfer system uses special paper rather than film; I did not
have good luck with it.

Some links on this topic that have accumulated in my bookmarks:

http://www.fullnet.com/u/tomg/gooteepc.htm
http://www.geocities.com/pdmtr/
http://www.cibs.co.uk/etch/x7.html

For ordering out, so to speak, a potentially cheaper option than dealing
directly with a PCB house is to pool your order with others (if you can
wait a short while) to share setup costs. These folks do this for you:

http://www.pcb-pool.com/

They've been mentioned favorably on sci.electronics.cad, but I haven't
tried them myself yet. They have an interesting front page....

Peace,
Tom

Scott Dorsey wrote:
I once made a bunch of phono preamps
with the positive resist stuff on the stove in the kitchen of my college
dorm and got a nasty letter from the school Housing department.

But isn't that 'cause your were dumping the ferric chloride etchant down the
kitchen sink?

Tim

Bryson wrote:
Scott Dorsey wrote:
I once made a bunch of phono preamps
with the positive resist stuff on the stove in the kitchen of my college
dorm and got a nasty letter from the school Housing department.

But isn't that 'cause your were dumping the ferric chloride etchant down the
kitchen sink?

I think it was mostly that i was using the stovetop to heat up pyrex
pans of ferric chloride.... it was a little corrosive.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Scott Dorsey wrote:

There is new material that can be run directly through xerox machines or
laser printers, then the toner image transferred onto a PC board with
a steam iron. This wasn't out when I was in the dorms, but I know folks
who have got very good results with it.

I bought some of that. I thought it was more work than drawing it
myself. You have to apply massive pressure with the iron to get the
toner to stick, and at that point you squish the toner and it smears.

I tend to use perfboard for the first design, then expresspcb for the next
couple variants.

I usually just prototype on Express PCB and fix any mistakes the hard
way. I don't use a spell-checker either.

ulysses
whose pencils don't need erasers

Justin Ulysses Morse wrote in message ...
Some people successfully etch double-sides boards but I would rather eat glass than hassle with that.

Mind if I join yah? munch munch