Homebrew_PCBs

This is a copy of a reply I just posted in sci.electronics.design. I thought I would
post it here as well for you folks to pursue if you are interested in it. Maybe
Crankorgan John could go work up some plans for it. It's promising technology
but I like working with boards more than belts and gears.

> >Has anyone every tried putting Etch resist Ink in a BubbleJet or InkJet
> >printer and printing a PCB design directy onto the copper side of a PCB.

As a matter of fact I have. I thought about turning this into a commercial product, but
I just don't have the time. Too many other projects to do. I even went so far as to
turn an inkjet into a flatbed plotter. The problem there is converting the stepper motor driven
motion of the platten roller into linear motion with the stepper using belts or gears or
electronic gear ratio reduction for the steps. All three methods work but I like the
belt and gears method best.

I tried modifying printers to feed a board through as is, but that was just too much trouble.
Some would feed thin stock just fine but others wouldn't. The flat bed approach solves that.
Plus the flat bed approach with some simple guide pins lets you do double sided boards with
accurate side to side registration.

For ink, I found two things that work well standing up to the etchant.

Acrylic Floor Polish.
Shellac

Floor polish ( sometimes called wax ) ( I used the Future brand ) works well and won't gum
up the printheads as easily as Shellac does.

Floor polish is removed with Ammonia.

Shellac with Denatured Alcohol.

I used three different types of printers. A Lexmark where the head is built into the cartridge,
an HP where the printhead is separate from the cartridge but still uses thermal "bubble" jet
technology and an Epson which uses piezoelectric technology.

The winner was the Lexmark. Easy cartridge to refill and cheap enough to replace.

The problem in all this is that to use straight "ink" that is very water ( and then etchant ) proof
is, it will dry on your printhead orifices. The solution to that is a valve. One path to ink, one path
to a flushing fluid. Before you print the board, run a cycle of "ink" to clear out all your flush fluid.
Once you have finished printing, run a cycle of flushing fluid to purge all your "ink".

Ammonia diluted with water works great on the acrylic polish ink. You can even put a little regular
inkjet ink into it to color it so it's easier to see on the PC board blank.

Once you get the "ink" on the board and have etched it, you can clean it off with just a quick spray of
Windex or other ammonia based cleaner.

I have no idea as to the benefits or problems with acrylics as conformal coatings but I plan to try it
some day on a finished board. Just dip it in Future polish and see what happens!

Another thought I had was a PVA ( poly vinyl alcohol ) based ink but the PVA I had on hand didn't
thin out well to run in an inkjet. The acrylic ink worked well enough so I didn't really pursue PVA much.

Now go have fun......

later,
Larry Edington.


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

Larry,
I sell plans for a PCBmill (Brute) and I just finished a
machine that will mill or draw simple boards. (Morph)
Months ago I brought up the idea of Scratch and Etch. This
idea is not dead. First I developed a super simple CNC plotter. Now
I have a machine strong enough to drag a scribe through the blueing.
Several people tried Scratch and Etch With good results. Coating the
whole board and then scribing and isolation between pads for etching
seems easier.

Crankorgan John

--- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...> wrote:
> This is a copy of a reply I just posted in sci.electronics.design.
I thought I would
> post it here as well for you folks to pursue if you are interested
in it. Maybe
> Crankorgan John could go work up some plans for it. It's promising
technology
> but I like working with boards more than belts and gears.
>
>
> > >Has anyone every tried putting Etch resist Ink in a BubbleJet
or InkJet
> > >printer and printing a PCB design directy onto the copper side
of a PCB.
>
> As a matter of fact I have. I thought about turning this into a
commercial product, but
> I just don't have the time. Too many other projects to do. I even
went so far as to
> turn an inkjet into a flatbed plotter. The problem there is
converting the stepper motor driven
> motion of the platten roller into linear motion with the stepper
using belts or gears or
> electronic gear ratio reduction for the steps. All three methods
work but I like the
> belt and gears method best.
>
> I tried modifying printers to feed a board through as is, but that
was just too much trouble.
> Some would feed thin stock just fine but others wouldn't. The flat
bed approach solves that.
> Plus the flat bed approach with some simple guide pins lets you do
double sided boards with
> accurate side to side registration.
>
> For ink, I found two things that work well standing up to the
etchant.
>
> Acrylic Floor Polish.
> Shellac
>
> Floor polish ( sometimes called wax ) ( I used the Future brand )
works well and won't gum
> up the printheads as easily as Shellac does.
>
> Floor polish is removed with Ammonia.
>
> Shellac with Denatured Alcohol.
>
> I used three different types of printers. A Lexmark where the head
is built into the cartridge,
> an HP where the printhead is separate from the cartridge but still
uses thermal "bubble" jet
> technology and an Epson which uses piezoelectric technology.
>
> The winner was the Lexmark. Easy cartridge to refill and cheap
enough to replace.
>
> The problem in all this is that to use straight "ink" that is very
water ( and then etchant ) proof
> is, it will dry on your printhead orifices. The solution to that is
a valve. One path to ink, one path
> to a flushing fluid. Before you print the board, run a cycle
of "ink" to clear out all your flush fluid.
> Once you have finished printing, run a cycle of flushing fluid to
purge all your "ink".
>
> Ammonia diluted with water works great on the acrylic polish ink.
You can even put a little regular
> inkjet ink into it to color it so it's easier to see on the PC
board blank.
>
> Once you get the "ink" on the board and have etched it, you can
clean it off with just a quick spray of
> Windex or other ammonia based cleaner.
>
> I have no idea as to the benefits or problems with acrylics as
conformal coatings but I plan to try it
> some day on a finished board. Just dip it in Future polish and see
what happens!
>
> Another thought I had was a PVA ( poly vinyl alcohol ) based ink
but the PVA I had on hand didn't
> thin out well to run in an inkjet. The acrylic ink worked well
enough so I didn't really pursue PVA much.
>
> Now go have fun......
>
> later,
> Larry Edington.
>
>
> [Non-text portions of this message have been removed]

Crankorgan,
Putting bluing on the whole board, then scratching it off with a
carbide metal scratch tip is the method I'm currently using to do boards. I
tape the copper down on a piece of paper, then run it through my HP plotter
(7550A). I get very clean lines and can get down to 10mil space 10mil line
with a bit of practice, double sided. I've written custom software to take a
Eagle board file and create HPGL which I then output to the plotter. This
method really works well since you can use a standard plotter (I just built
a special 'pen' with the carbide scratch tip) plus some software. Anyway,
the bluing/scratching method is alive and well . . .

*Brian


-----Original Message-----
From: crankorgan [mailto:john@...]
Sent: Saturday, September 14, 2002 6:41 AM
To: Homebrew_PCBs@yahoogroups.com
Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards


Larry,
I sell plans for a PCBmill (Brute) and I just finished a
machine that will mill or draw simple boards. (Morph)
Months ago I brought up the idea of Scratch and Etch. This
idea is not dead. First I developed a super simple CNC plotter. Now
I have a machine strong enough to drag a scribe through the blueing.
Several people tried Scratch and Etch With good results. Coating the
whole board and then scribing and isolation between pads for etching
seems easier.

Crankorgan John

Hi Brian,
I bought a plotter. Two things I did not like. 1. It wanted
PLT files. I use GCode. 2. The plotter can't drill the boards. 3.The
plotter can't mill the boards. So I designed a simple cheap machine
that could do it all. It will also do 3D work in wood. I bought a
Roland plotter. I could not beleive how cheaply it was made! But it
led to the Morph design.

John Crankorgan Kleinbauer

www.kleinbauer.com/

--- In Homebrew_PCBs@y..., Brian Schmalz <brian.s@l...> wrote:
> Crankorgan,
> Putting bluing on the whole board, then scratching it off
with a
> carbide metal scratch tip is the method I'm currently using to do
boards. I
> tape the copper down on a piece of paper, then run it through my HP
plotter
> (7550A). I get very clean lines and can get down to 10mil space
10mil line
> with a bit of practice, double sided. I've written custom software
to take a
> Eagle board file and create HPGL which I then output to the
plotter. This
> method really works well since you can use a standard plotter (I
just built
> a special 'pen' with the carbide scratch tip) plus some software.
Anyway,
> the bluing/scratching method is alive and well . . .
>
> *Brian
>
>
> -----Original Message-----
> From: crankorgan [mailto:john@k...]
> Sent: Saturday, September 14, 2002 6:41 AM
> To: Homebrew_PCBs@y...
> Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards
>
>
> Larry,
> I sell plans for a PCBmill (Brute) and I just finished a
> machine that will mill or draw simple boards. (Morph)
> Months ago I brought up the idea of Scratch and Etch. This
> idea is not dead. First I developed a super simple CNC plotter. Now
> I have a machine strong enough to drag a scribe through the blueing.
> Several people tried Scratch and Etch With good results. Coating
the
> whole board and then scribing and isolation between pads for
etching
> seems easier.
>
> Crankorgan John

Hi Brian, John,

What about using a diamond engraver tip? I bought one (mistakenly)
thinking it was for machining (it was for the Dremel engraver). But I'm
thinking one could drag it around as well. I can "read" Gerber files
with my controller program, and I generate "outline" tool paths. from
that.

Alan KM6VV

Brian Schmalz wrote:

>
> Crankorgan,
> Putting bluing on the whole board, then scratching it off with a
> carbide metal scratch tip is the method I'm currently using to do boards. I
> tape the copper down on a piece of paper, then run it through my HP plotter
> (7550A). I get very clean lines and can get down to 10mil space 10mil line
> with a bit of practice, double sided. I've written custom software to take a
> Eagle board file and create HPGL which I then output to the plotter. This
> method really works well since you can use a standard plotter (I just built
> a special 'pen' with the carbide scratch tip) plus some software. Anyway,
> the bluing/scratching method is alive and well . . .
>
> *Brian
>
> -----Original Message-----
> From: crankorgan [mailto:john@...]
> Sent: Saturday, September 14, 2002 6:41 AM
> To: Homebrew_PCBs@yahoogroups.com
> Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards
>
> Larry,
> I sell plans for a PCBmill (Brute) and I just finished a
> machine that will mill or draw simple boards. (Morph)
> Months ago I brought up the idea of Scratch and Etch. This
> idea is not dead. First I developed a super simple CNC plotter. Now
> I have a machine strong enough to drag a scribe through the blueing.
> Several people tried Scratch and Etch With good results. Coating the
> whole board and then scribing and isolation between pads for etching
> seems easier.

The problem with scratch and etch is the same as milling. Users must have a toolpath calculation program to
generate the outline toolpaths. In practical terms, that's expensive for robust software that can do small trace
pitches.

Outline paths also have the problem of "islands" of varying sizes which can cause a lot of problems
for high speed boards. I don't think you could practically route a differential trace pair with isolations. There would
be an enormous amount of rubouts required to clear all the copper between the traces but keep the traces at the
proper spacing and width for the correct impedence. One tiny hair of copper running along between your traces
can really mess up the signalling. I wouldn't even try an LVDS bus with isolation.

Sure, Eagle can do outline paths but not everybody uses Eagle. T-Tech's Isolator Pro does excellent toolpaths
but is expensive!. KellyCam generates pretty good toolpaths but sucks as a CNC controller. I always used Isolator
Pro for toolpaths when I did mechanical etching.

I played around with "scratch and etch" too for a while. I also plotted directly to copper using modified drafting pens
filled with acrylic floor polish. The smallest pen I have found locally is a .18 mm tip technical pen. That produces a trace
of .0070866 wide. So it's a 7 mil trace. I successfully plotted and etched some 48 pin TSOP to 48 pin DIP adapter
boards so I could read some flash roms on my programmer. But it was SLOW! Also filled areas like pads
had concentric circles in them where the carbide pen tip scratched into the just layed down path of resist.

However, using Inkjets produces solid fills with no voids. No special software is needed either. All you need is
something that can print your gerber files to a standard printer.

Modern inkjet printers are fast and are accurate enough to do some very small trace widths and spacings.

You could also lay down solder mask and the component identifiers using the same modified printer.

While I agree that the scratch and etch idea is great, and has some benefits over direct resist application, the biggest
downside I see is the problem of the toolpath generation for the average user. Also, the tool must be tightly controlled
to produce the necessary isolation path widths. For me the perfect width would be a 5 mil tool. But will a tool that is
.005 wide cut a clean swipe through the bluing without splintered edges? If your tool has a very sharp tip, then you'll
need multiple passes to get a 5 to 10 mill isolation path. I never got a clean enough path through the resist. "furry"
or jagged edges on traces also cause lots of noise problems on high speed circuits.

The market for these products are not just hobbiests. There are a lot of us guys out there that make their living in the
electronics industry that would LOVE to have something to quickly make a board without having to send it out!
Lots of corporations would buy them for the EE labs!

I just wish someone would run with it and work out all the bugs so I could just buy one. I want to make boards not
tools to make boards.

later,
Larry E.

----- Original Message -----
From: crankorgan
To: Homebrew_PCBs@yahoogroups.com
Sent: Saturday, September 14, 2002 6:41 AM
Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards


Larry,
I sell plans for a PCBmill (Brute) and I just finished a
machine that will mill or draw simple boards. (Morph)
Months ago I brought up the idea of Scratch and Etch. This
idea is not dead. First I developed a super simple CNC plotter. Now
I have a machine strong enough to drag a scribe through the blueing.
Several people tried Scratch and Etch With good results. Coating the
whole board and then scribing and isolation between pads for etching
seems easier.

Crankorgan John


--- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...> wrote:
> This is a copy of a reply I just posted in sci.electronics.design.
I thought I would
> post it here as well for you folks to pursue if you are interested
in it. Maybe
> Crankorgan John could go work up some plans for it. It's promising
technology
> but I like working with boards more than belts and gears.
>
>
> > >Has anyone every tried putting Etch resist Ink in a BubbleJet
or InkJet
> > >printer and printing a PCB design directy onto the copper side
of a PCB.
>
> As a matter of fact I have. I thought about turning this into a
commercial product, but
> I just don't have the time. Too many other projects to do. I even
went so far as to
> turn an inkjet into a flatbed plotter. The problem there is
converting the stepper motor driven
> motion of the platten roller into linear motion with the stepper
using belts or gears or
> electronic gear ratio reduction for the steps. All three methods
work but I like the
> belt and gears method best.
>
> I tried modifying printers to feed a board through as is, but that
was just too much trouble.
> Some would feed thin stock just fine but others wouldn't. The flat
bed approach solves that.
> Plus the flat bed approach with some simple guide pins lets you do
double sided boards with
> accurate side to side registration.
>
> For ink, I found two things that work well standing up to the
etchant.
>
> Acrylic Floor Polish.
> Shellac
>
> Floor polish ( sometimes called wax ) ( I used the Future brand )
works well and won't gum
> up the printheads as easily as Shellac does.
>
> Floor polish is removed with Ammonia.
>
> Shellac with Denatured Alcohol.
>
> I used three different types of printers. A Lexmark where the head
is built into the cartridge,
> an HP where the printhead is separate from the cartridge but still
uses thermal "bubble" jet
> technology and an Epson which uses piezoelectric technology.
>
> The winner was the Lexmark. Easy cartridge to refill and cheap
enough to replace.
>
> The problem in all this is that to use straight "ink" that is very
water ( and then etchant ) proof
> is, it will dry on your printhead orifices. The solution to that is
a valve. One path to ink, one path
> to a flushing fluid. Before you print the board, run a cycle
of "ink" to clear out all your flush fluid.
> Once you have finished printing, run a cycle of flushing fluid to
purge all your "ink".
>
> Ammonia diluted with water works great on the acrylic polish ink.
You can even put a little regular
> inkjet ink into it to color it so it's easier to see on the PC
board blank.
>
> Once you get the "ink" on the board and have etched it, you can
clean it off with just a quick spray of
> Windex or other ammonia based cleaner.
>
> I have no idea as to the benefits or problems with acrylics as
conformal coatings but I plan to try it
> some day on a finished board. Just dip it in Future polish and see
what happens!
>
> Another thought I had was a PVA ( poly vinyl alcohol ) based ink
but the PVA I had on hand didn't
> thin out well to run in an inkjet. The acrylic ink worked well
enough so I didn't really pursue PVA much.
>
> Now go have fun......
>
> later,
> Larry Edington.
>
>
> [Non-text portions of this message have been removed]


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

Hi Alan,
Layout blue is made to be just scratched. It has been around
for 75 years. The trick is to have your traces drawn with an overlap.
During the scratching process you can be sure the trace is isolated
cleanly. The only drawback is all the traces are surrounded by a
ground plane. This is the same result as milling them. I use the
ground plane for my ground connections. Most digital circuits work
just fine with the extra copper. High end receivers use ground
planes. There is no simple way to make a PCBoard. Even sending them
out can have headaches.

Cranky

--- In Homebrew_PCBs@y..., Alan Marconett KM6VV <KM6VV@a...> wrote:
> Hi Brian, John,
>
> What about using a diamond engraver tip? I bought one (mistakenly)
> thinking it was for machining (it was for the Dremel engraver).
But I'm
> thinking one could drag it around as well. I can "read" Gerber
files
> with my controller program, and I generate "outline" tool paths.
from
> that.
>
> Alan KM6VV
>
> Brian Schmalz wrote:
> >
> > Crankorgan,
> > Putting bluing on the whole board, then scratching it off
with a
> > carbide metal scratch tip is the method I'm currently using to do
boards. I
> > tape the copper down on a piece of paper, then run it through my
HP plotter
> > (7550A). I get very clean lines and can get down to 10mil space
10mil line
> > with a bit of practice, double sided. I've written custom
software to take a
> > Eagle board file and create HPGL which I then output to the
plotter. This
> > method really works well since you can use a standard plotter (I
just built
> > a special 'pen' with the carbide scratch tip) plus some software.
Anyway,
> > the bluing/scratching method is alive and well . . .
> >
> > *Brian
> >
> > -----Original Message-----
> > From: crankorgan [mailto:john@k...]
> > Sent: Saturday, September 14, 2002 6:41 AM
> > To: Homebrew_PCBs@y...
> > Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards
> >
> > Larry,
> > I sell plans for a PCBmill (Brute) and I just finished a
> > machine that will mill or draw simple boards. (Morph)
> > Months ago I brought up the idea of Scratch and Etch. This
> > idea is not dead. First I developed a super simple CNC plotter.
Now
> > I have a machine strong enough to drag a scribe through the
blueing.
> > Several people tried Scratch and Etch With good results. Coating
the
> > whole board and then scribing and isolation between pads for
etching
> > seems easier.

Larry and others,
If you print onto a sheet of plastic with an inkjet and
put it into the acid for us. I am out of acid right now. Let us
know if the inkjet ink holds up! If it does then the idea is
valid. I remember a guy from Texas asking me about printing directly
onto copper. I am overwhelmed with projects right now and it has been
too hot this summer. I burned out trying to finish the Morph!

Cranky

--- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...> wrote:
> The problem with scratch and etch is the same as milling. Users
must have a toolpath calculation program to
> generate the outline toolpaths. In practical terms, that's
expensive for robust software that can do small trace
> pitches.
>
> Outline paths also have the problem of "islands" of varying sizes
which can cause a lot of problems
> for high speed boards. I don't think you could practically route a
differential trace pair with isolations. There would
> be an enormous amount of rubouts required to clear all the copper
between the traces but keep the traces at the
> proper spacing and width for the correct impedence. One tiny hair
of copper running along between your traces
> can really mess up the signalling. I wouldn't even try an LVDS bus
with isolation.
>
> Sure, Eagle can do outline paths but not everybody uses Eagle. T-
Tech's Isolator Pro does excellent toolpaths
> but is expensive!. KellyCam generates pretty good toolpaths but
sucks as a CNC controller. I always used Isolator
> Pro for toolpaths when I did mechanical etching.
>
> I played around with "scratch and etch" too for a while. I also
plotted directly to copper using modified drafting pens
> filled with acrylic floor polish. The smallest pen I have found
locally is a .18 mm tip technical pen. That produces a trace
> of .0070866 wide. So it's a 7 mil trace. I successfully plotted and
etched some 48 pin TSOP to 48 pin DIP adapter
> boards so I could read some flash roms on my programmer. But it was
SLOW! Also filled areas like pads
> had concentric circles in them where the carbide pen tip scratched
into the just layed down path of resist.
>
> However, using Inkjets produces solid fills with no voids. No
special software is needed either. All you need is
> something that can print your gerber files to a standard printer.
>
> Modern inkjet printers are fast and are accurate enough to do some
very small trace widths and spacings.
>
> You could also lay down solder mask and the component identifiers
using the same modified printer.
>
> While I agree that the scratch and etch idea is great, and has some
benefits over direct resist application, the biggest
> downside I see is the problem of the toolpath generation for the
average user. Also, the tool must be tightly controlled
> to produce the necessary isolation path widths. For me the perfect
width would be a 5 mil tool. But will a tool that is
> .005 wide cut a clean swipe through the bluing without splintered
edges? If your tool has a very sharp tip, then you'll
> need multiple passes to get a 5 to 10 mill isolation path. I never
got a clean enough path through the resist. "furry"
> or jagged edges on traces also cause lots of noise problems on high
speed circuits.
>
> The market for these products are not just hobbiests. There are a
lot of us guys out there that make their living in the
> electronics industry that would LOVE to have something to quickly
make a board without having to send it out!
> Lots of corporations would buy them for the EE labs!
>
> I just wish someone would run with it and work out all the bugs so
I could just buy one. I want to make boards not
> tools to make boards.
>
> later,
> Larry E.
>
>
>
> ----- Original Message -----
> From: crankorgan
> To: Homebrew_PCBs@y...
> Sent: Saturday, September 14, 2002 6:41 AM
> Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards
>
>
> Larry,
> I sell plans for a PCBmill (Brute) and I just finished a
> machine that will mill or draw simple boards. (Morph)
> Months ago I brought up the idea of Scratch and Etch. This
> idea is not dead. First I developed a super simple CNC plotter.
Now
> I have a machine strong enough to drag a scribe through the
blueing.
> Several people tried Scratch and Etch With good results. Coating
the
> whole board and then scribing and isolation between pads for
etching
> seems easier.
>
> Crankorgan John
>
>
> --- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...>
wrote:
> > This is a copy of a reply I just posted in
sci.electronics.design.
> I thought I would
> > post it here as well for you folks to pursue if you are
interested
> in it. Maybe
> > Crankorgan John could go work up some plans for it. It's
promising
> technology
> > but I like working with boards more than belts and gears.
> >
> >
> > > >Has anyone every tried putting Etch resist Ink in a
BubbleJet
> or InkJet
> > > >printer and printing a PCB design directy onto the copper
side
> of a PCB.
> >
> > As a matter of fact I have. I thought about turning this into a
> commercial product, but
> > I just don't have the time. Too many other projects to do. I
even
> went so far as to
> > turn an inkjet into a flatbed plotter. The problem there is
> converting the stepper motor driven
> > motion of the platten roller into linear motion with the
stepper
> using belts or gears or
> > electronic gear ratio reduction for the steps. All three
methods
> work but I like the
> > belt and gears method best.
> >
> > I tried modifying printers to feed a board through as is, but
that
> was just too much trouble.
> > Some would feed thin stock just fine but others wouldn't. The
flat
> bed approach solves that.
> > Plus the flat bed approach with some simple guide pins lets you
do
> double sided boards with
> > accurate side to side registration.
> >
> > For ink, I found two things that work well standing up to the
> etchant.
> >
> > Acrylic Floor Polish.
> > Shellac
> >
> > Floor polish ( sometimes called wax ) ( I used the Future
brand )
> works well and won't gum
> > up the printheads as easily as Shellac does.
> >
> > Floor polish is removed with Ammonia.
> >
> > Shellac with Denatured Alcohol.
> >
> > I used three different types of printers. A Lexmark where the
head
> is built into the cartridge,
> > an HP where the printhead is separate from the cartridge but
still
> uses thermal "bubble" jet
> > technology and an Epson which uses piezoelectric technology.
> >
> > The winner was the Lexmark. Easy cartridge to refill and cheap
> enough to replace.
> >
> > The problem in all this is that to use straight "ink" that is
very
> water ( and then etchant ) proof
> > is, it will dry on your printhead orifices. The solution to
that is
> a valve. One path to ink, one path
> > to a flushing fluid. Before you print the board, run a cycle
> of "ink" to clear out all your flush fluid.
> > Once you have finished printing, run a cycle of flushing fluid
to
> purge all your "ink".
> >
> > Ammonia diluted with water works great on the acrylic polish
ink.
> You can even put a little regular
> > inkjet ink into it to color it so it's easier to see on the PC
> board blank.
> >
> > Once you get the "ink" on the board and have etched it, you can
> clean it off with just a quick spray of
> > Windex or other ammonia based cleaner.
> >
> > I have no idea as to the benefits or problems with acrylics as
> conformal coatings but I plan to try it
> > some day on a finished board. Just dip it in Future polish and
see
> what happens!
> >
> > Another thought I had was a PVA ( poly vinyl alcohol ) based
ink
> but the PVA I had on hand didn't
> > thin out well to run in an inkjet. The acrylic ink worked well
> enough so I didn't really pursue PVA much.
> >
> > Now go have fun......
> >
> > later,
> > Larry Edington.
> >
> >
> > [Non-text portions of this message have been removed]
>
>
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None of the standard Inkjet inks that I tried would even stand up to water much less etchant.

Epson 1520, Epson C80, HP 1000C, Lexmark Waterproof, Generic HP refill, Generic Epson refill.

None of these would withstand ferric chloride or ammonium persulfate etchant.

A shocking thing I found out is that Sharpie ink which I've used for years to touch up boards when etched
with ferric chloride just floated away in my ammonium persulfate etchant.

later,
Larry E.

----- Original Message -----
From: crankorgan
To: Homebrew_PCBs@yahoogroups.com
Sent: Saturday, September 14, 2002 3:32 PM
Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards


Larry and others,
If you print onto a sheet of plastic with an inkjet and
put it into the acid for us. I am out of acid right now. Let us
know if the inkjet ink holds up! If it does then the idea is
valid. I remember a guy from Texas asking me about printing directly
onto copper. I am overwhelmed with projects right now and it has been
too hot this summer. I burned out trying to finish the Morph!

Cranky




--- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...> wrote:
> The problem with scratch and etch is the same as milling. Users
must have a toolpath calculation program to
> generate the outline toolpaths. In practical terms, that's
expensive for robust software that can do small trace
> pitches.
>
> Outline paths also have the problem of "islands" of varying sizes
which can cause a lot of problems
> for high speed boards. I don't think you could practically route a
differential trace pair with isolations. There would
> be an enormous amount of rubouts required to clear all the copper
between the traces but keep the traces at the
> proper spacing and width for the correct impedence. One tiny hair
of copper running along between your traces
> can really mess up the signalling. I wouldn't even try an LVDS bus
with isolation.
>
> Sure, Eagle can do outline paths but not everybody uses Eagle. T-
Tech's Isolator Pro does excellent toolpaths
> but is expensive!. KellyCam generates pretty good toolpaths but
sucks as a CNC controller. I always used Isolator
> Pro for toolpaths when I did mechanical etching.
>
> I played around with "scratch and etch" too for a while. I also
plotted directly to copper using modified drafting pens
> filled with acrylic floor polish. The smallest pen I have found
locally is a .18 mm tip technical pen. That produces a trace
> of .0070866 wide. So it's a 7 mil trace. I successfully plotted and
etched some 48 pin TSOP to 48 pin DIP adapter
> boards so I could read some flash roms on my programmer. But it was
SLOW! Also filled areas like pads
> had concentric circles in them where the carbide pen tip scratched
into the just layed down path of resist.
>
> However, using Inkjets produces solid fills with no voids. No
special software is needed either. All you need is
> something that can print your gerber files to a standard printer.
>
> Modern inkjet printers are fast and are accurate enough to do some
very small trace widths and spacings.
>
> You could also lay down solder mask and the component identifiers
using the same modified printer.
>
> While I agree that the scratch and etch idea is great, and has some
benefits over direct resist application, the biggest
> downside I see is the problem of the toolpath generation for the
average user. Also, the tool must be tightly controlled
> to produce the necessary isolation path widths. For me the perfect
width would be a 5 mil tool. But will a tool that is
> .005 wide cut a clean swipe through the bluing without splintered
edges? If your tool has a very sharp tip, then you'll
> need multiple passes to get a 5 to 10 mill isolation path. I never
got a clean enough path through the resist. "furry"
> or jagged edges on traces also cause lots of noise problems on high
speed circuits.
>
> The market for these products are not just hobbiests. There are a
lot of us guys out there that make their living in the
> electronics industry that would LOVE to have something to quickly
make a board without having to send it out!
> Lots of corporations would buy them for the EE labs!
>
> I just wish someone would run with it and work out all the bugs so
I could just buy one. I want to make boards not
> tools to make boards.
>
> later,
> Larry E.
>
>
>
> ----- Original Message -----
> From: crankorgan
> To: Homebrew_PCBs@y...
> Sent: Saturday, September 14, 2002 6:41 AM
> Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards
>
>
> Larry,
> I sell plans for a PCBmill (Brute) and I just finished a
> machine that will mill or draw simple boards. (Morph)
> Months ago I brought up the idea of Scratch and Etch. This
> idea is not dead. First I developed a super simple CNC plotter.
Now
> I have a machine strong enough to drag a scribe through the
blueing.
> Several people tried Scratch and Etch With good results. Coating
the
> whole board and then scribing and isolation between pads for
etching
> seems easier.
>
> Crankorgan John
>
>
> --- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...>
wrote:
> > This is a copy of a reply I just posted in
sci.electronics.design.
> I thought I would
> > post it here as well for you folks to pursue if you are
interested
> in it. Maybe
> > Crankorgan John could go work up some plans for it. It's
promising
> technology
> > but I like working with boards more than belts and gears.
> >
> >
> > > >Has anyone every tried putting Etch resist Ink in a
BubbleJet
> or InkJet
> > > >printer and printing a PCB design directy onto the copper
side
> of a PCB.
> >
> > As a matter of fact I have. I thought about turning this into a
> commercial product, but
> > I just don't have the time. Too many other projects to do. I
even
> went so far as to
> > turn an inkjet into a flatbed plotter. The problem there is
> converting the stepper motor driven
> > motion of the platten roller into linear motion with the
stepper
> using belts or gears or
> > electronic gear ratio reduction for the steps. All three
methods
> work but I like the
> > belt and gears method best.
> >
> > I tried modifying printers to feed a board through as is, but
that
> was just too much trouble.
> > Some would feed thin stock just fine but others wouldn't. The
flat
> bed approach solves that.
> > Plus the flat bed approach with some simple guide pins lets you
do
> double sided boards with
> > accurate side to side registration.
> >
> > For ink, I found two things that work well standing up to the
> etchant.
> >
> > Acrylic Floor Polish.
> > Shellac
> >
> > Floor polish ( sometimes called wax ) ( I used the Future
brand )
> works well and won't gum
> > up the printheads as easily as Shellac does.
> >
> > Floor polish is removed with Ammonia.
> >
> > Shellac with Denatured Alcohol.
> >
> > I used three different types of printers. A Lexmark where the
head
> is built into the cartridge,
> > an HP where the printhead is separate from the cartridge but
still
> uses thermal "bubble" jet
> > technology and an Epson which uses piezoelectric technology.
> >
> > The winner was the Lexmark. Easy cartridge to refill and cheap
> enough to replace.
> >
> > The problem in all this is that to use straight "ink" that is
very
> water ( and then etchant ) proof
> > is, it will dry on your printhead orifices. The solution to
that is
> a valve. One path to ink, one path
> > to a flushing fluid. Before you print the board, run a cycle
> of "ink" to clear out all your flush fluid.
> > Once you have finished printing, run a cycle of flushing fluid
to
> purge all your "ink".
> >
> > Ammonia diluted with water works great on the acrylic polish
ink.
> You can even put a little regular
> > inkjet ink into it to color it so it's easier to see on the PC
> board blank.
> >
> > Once you get the "ink" on the board and have etched it, you can
> clean it off with just a quick spray of
> > Windex or other ammonia based cleaner.
> >
> > I have no idea as to the benefits or problems with acrylics as
> conformal coatings but I plan to try it
> > some day on a finished board. Just dip it in Future polish and
see
> what happens!
> >
> > Another thought I had was a PVA ( poly vinyl alcohol ) based
ink
> but the PVA I had on hand didn't
> > thin out well to run in an inkjet. The acrylic ink worked well
> enough so I didn't really pursue PVA much.
> >
> > Now go have fun......
> >
> > later,
> > Larry Edington.
> >
> >
> > [Non-text portions of this message have been removed]
>
>
> Yahoo! Groups Sponsor
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Service.
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> [Non-text portions of this message have been removed]


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

I notice Canon isn't on your list. Most of the Canon printers are
built so that although you normally replace just the ink carts, you
can remove and replace the heads as easily as replacing a
cartridge. I don't expect the inks to hold up in water or etchant
any better.

However, it would mean 1. no flushing between carts, just have two
sets of heads and 2. remove and place in the holder you get with a
replacement head, perhaps with a drop of water in the part that
seals around the print nozzles to keep them from clogging.

My Canon BJC6000 has a straight through paper path. I doubt it
could handle 1/16th inch PCB, but I have some PCB that is as thin
as thick cardstock. The heads can be set for cardstock, too. I'm a
bit leary of testing this with my only inkjet, as you can imagine,
as I use it for photo printing. I'm going to keep my eyes open in
the thrift stores for another Canon with straight through paper
path.

Something I suggested before: what about those Alps-based CD
printers? The ones that print wax thermal directly onto a CD?
Modify it slightly to take a square PCB. Only concern is pinholes.
And if that occurs, it might be solved by a short bake cycle.

Those printers aren't cheap, but I can see many advantages over
other methods.

Steve Greenfield

--- Larry Edington <ledington@...> wrote:

> None of the standard Inkjet inks that I tried would even stand up
> to water much less etchant.
>
> Epson 1520, Epson C80, HP 1000C, Lexmark Waterproof, Generic HP
> refill, Generic Epson refill.
>
> None of these would withstand ferric chloride or ammonium
> persulfate etchant.
>
> A shocking thing I found out is that Sharpie ink which I've used
> for years to touch up boards when etched
> with ferric chloride just floated away in my ammonium persulfate
> etchant.
>
> later,
> Larry E.

__________________________________________________
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No, I didn't look at any of the Canon printers.

The Lexmark however has an even better solution than changing heads.

It has a rubber cup the head sits down on when the head is parked to prevent drying. I would fill that cup with ammonia
water and the head didn't clog until I let the ammonia get too low to touch the head. The ideal solution there
would be to fit a tube into that cup and pressure wash the head when it was parked. The normal inkjet
clean before printing cycle flushes out any residual solvent from the surface of the head.

Or a sponge wiper could be put in the path of the head so that when it moved away from the cup it
moved across the sponge to wipe any solvent.

The Lexmark printers are cheap too! Plus the carriage is light enough to mount on a Y axis. The only
remaining problem is to make the Y move the correct distance with each step of the existing stepper
motor.

The wax printer is something that should be investigated. What about the dye sublimation printers like
the Fargo Primera line that used a wax cartridge in 3 colors. Those were waterproof as a standard feature.

later,
Larry E.

----- Original Message -----
From: Steve Greenfield
To: Homebrew_PCBs@yahoogroups.com
Sent: Saturday, September 14, 2002 4:46 PM
Subject: Re: [Homebrew_PCBs] Re: Inkjet printing PC boards


I notice Canon isn't on your list. Most of the Canon printers are
built so that although you normally replace just the ink carts, you
can remove and replace the heads as easily as replacing a
cartridge. I don't expect the inks to hold up in water or etchant
any better.

However, it would mean 1. no flushing between carts, just have two
sets of heads and 2. remove and place in the holder you get with a
replacement head, perhaps with a drop of water in the part that
seals around the print nozzles to keep them from clogging.

My Canon BJC6000 has a straight through paper path. I doubt it
could handle 1/16th inch PCB, but I have some PCB that is as thin
as thick cardstock. The heads can be set for cardstock, too. I'm a
bit leary of testing this with my only inkjet, as you can imagine,
as I use it for photo printing. I'm going to keep my eyes open in
the thrift stores for another Canon with straight through paper
path.

Something I suggested before: what about those Alps-based CD
printers? The ones that print wax thermal directly onto a CD?
Modify it slightly to take a square PCB. Only concern is pinholes.
And if that occurs, it might be solved by a short bake cycle.

Those printers aren't cheap, but I can see many advantages over
other methods.

Steve Greenfield

--- Larry Edington <ledington@...> wrote:
> None of the standard Inkjet inks that I tried would even stand up
> to water much less etchant.
>
> Epson 1520, Epson C80, HP 1000C, Lexmark Waterproof, Generic HP
> refill, Generic Epson refill.
>
> None of these would withstand ferric chloride or ammonium
> persulfate etchant.
>
> A shocking thing I found out is that Sharpie ink which I've used
> for years to touch up boards when etched
> with ferric chloride just floated away in my ammonium persulfate
> etchant.
>
> later,
> Larry E.


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

--- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...> wrote:

> No, I didn't look at any of the Canon printers.
>
> The Lexmark however has an even better solution than changing heads.
>
> It has a rubber cup the head sits down on when the head is parked

to prevent drying. I would fill that cup with ammonia

> water and the head didn't clog until I let the ammonia get too low

to touch the head. The ideal solution there

> would be to fit a tube into that cup and pressure wash the head

when it was parked. The normal inkjet

> clean before printing cycle flushes out any residual solvent from

the surface of the head.

I think all inkjet printers have that rubber cup. The holder for HP
and Canon print heads has the rubber cup.

The only reason I talked about changing heads is so you can use the
same printer for regular printing, too. Put in heads with regular ink
and print a test of the pattern, then drop in the etch resist heads
and print the final.

It also means the printer does not become junk if (when) the heads
clog. If you can take the heads out, you can soak them in ammonia or
just replace them easily.

I like the flushing idea. Just two tubes in the rubber cup, one in
and one out. A couple of CC's pumped through would be enough to fill
the cup and flush the head. One sheet printed before printing on the
copper should be enough to flush the ammonia and provide visual
confirmation that it is flushed.

> Or a sponge wiper could be put in the path of the head so that when

it moved away from the cup it

> moved across the sponge to wipe any solvent.
>
> The Lexmark printers are cheap too! Plus the carriage is light

enough to mount on a Y axis. The only

> remaining problem is to make the Y move the correct distance with

each step of the existing stepper

> motor.

I suppose, but they are built cheap, too, with tiny ink carts. Of
course if it works, it works.

> The wax printer is something that should be investigated. What

about the dye sublimation printers like

> the Fargo Primera line that used a wax cartridge in 3 colors. Those

were waterproof as a standard feature.

Those are almost totally immune to banding because they use a full
width ribbon. I used to have a Fargo Primera Pro, and they make very
robust printers. Fargo does make some of the CD wax thermal printers
and ID badge printers. ID badges would be kind of a small size, plus
I think the IDs are dye sub only. Dye sub is just a dye, has to be
absorbed by a coating and won't coat anything by itself.

I love this list!

Steve Greenfield

Hi Larry and Steve,

This is OT but I have a problem that I think you might be able to
help with. My wife has a Lexmark printer that the color cartridge only
lasts for one print session and then dries up. The black will last
until it runs out of ink. Of course at $20+ per cart, she doesn't
use color. Based on your comments, it seems like the color cart
doesn't sit properly on the rubber cup, (I didn't even know about
the rubber cups til now). I see what you are talking about, looks
sorta look like an empty IC socket. Spring loaded, both seem free
to move up and down. But I can't see what they look like when the
heads are parked. Do they move down while the head is traveling
and then move up? Would a few drops of some sort of solvent in the
cups help?
Also, is there any way to restore a cart with a dried head, but should
still be full of ink? I just now tried scrubbing one with a Q-tip
and water, (have tried alcohol, etc.) Was able to get yellow, red
and blue ink to flow out onto a paper towel, but it wouldn't print.
She ran 15 sheets thru in the test/clean mode and it spit and
sputtered all colors, but not usable. Any advice is greatly
appreciated.

Thanks in advance,
Al Lenz
P.S. Yes Steve this is a really GREAT group. I have used several of
the ideas presented here with success.
al

--- In Homebrew_PCBs@y..., "Steve G" <alienrelics@y...> wrote:
> --- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...> wrote:
> > No, I didn't look at any of the Canon printers.
> >
> > The Lexmark however has an even better solution than changing
heads.
> >
> > It has a rubber cup the head sits down on when the head is parked
> to prevent drying.

<snip>
> I think all inkjet printers have that rubber cup. The holder for HP
> and Canon print heads has the rubber cup.

<snip>

One of the reasons I don't want to risk my BJC 6000 is because
print heads are very delicate.

It is very possible that you ruined the head by scrubbing. Cotton
is actually very abrasive and the heads are very delicate. I've
used the chamois sticks that are used for cleaning VCR heads for
gently cleaning a print head. But I've had better luck with soaking
the print head first in distilled water.

Don't know on the Lexmark, but in Canon printers the heads move
down onto the cups as they park.

What is she printing in color? Just some color text on the page, or
a full page photo? Many of the Lexmark inkjets have hardly any ink
in them, but they should still last longer than one page.

Let me guess- this is one of those deals where the printer ended up
free or nearly free after rebates? They count on making money on
the ink carts.

Steve Greenfield

--- alenz2002 <alenz@...> wrote:

> Hi Larry and Steve,
>
> This is OT but I have a problem that I think you might be able to
> help with. My wife has a Lexmark printer that the color cartridge
> only
> lasts for one print session and then dries up. The black will
> last
> until it runs out of ink. Of course at $20+ per cart, she doesn't
>
> use color. Based on your comments, it seems like the color cart
> doesn't sit properly on the rubber cup, (I didn't even know about
> the rubber cups til now). I see what you are talking about,
> looks
> sorta look like an empty IC socket. Spring loaded, both seem
> free
> to move up and down. But I can't see what they look like when the
>
> heads are parked. Do they move down while the head is traveling
> and then move up? Would a few drops of some sort of solvent in
> the
> cups help?
> Also, is there any way to restore a cart with a dried head, but
> should
> still be full of ink? I just now tried scrubbing one with a
> Q-tip
> and water, (have tried alcohol, etc.) Was able to get yellow, red
>
> and blue ink to flow out onto a paper towel, but it wouldn't
> print.
> She ran 15 sheets thru in the test/clean mode and it spit and
> sputtered all colors, but not usable. Any advice is greatly
> appreciated.
>
> Thanks in advance,
> Al Lenz
> P.S. Yes Steve this is a really GREAT group. I have used several
> of
> the ideas presented here with success.
> al
>

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Hi John,

Saw your site. Nice implementation on Morph!

Alan KM6VV

crankorgan wrote:

>
> Hi Alan,
> Yes using a spinning scribe would make a wider path. I
> have an animation on my webpage. Let it load and you will see
> a pic of each side of the machine. One guy built a clone of the
> Morph by just looking at the pics.
>
> John
>
> --- In Homebrew_PCBs@y..., Alan Marconett KM6VV <KM6VV@a...> wrote:
> > Hi John,
> >
> > What about a small rotating burnishing tool, so the "scratches"
> would
> > have some width? I can see that this would be very similar to
> milling
> > the isolation traces.
> >
> > Alan KM6VV
> > P.S. Heard you've got a new mill/plotter working? pix?
> >

Steve Greenfield wrote:

> Let me guess- this is one of those deals where the printer ended up
> free or nearly free after rebates? They count on making money on
> the ink carts.

Seve, Good Guess! A 'free' scanner came with my computer. It didn't
work, so they sent a 'free' printer, (the promo scanner had been
replaced by a promo printer). Told me they didn't want the scanner
back, just trash it. Tells you how much they have invested in those
freebies. Anyhow couldn't trash the scanner without taking it
apart! Was easy to fix, the ribbon cable was misrouted causing it
to hang up. So since the printer was a freebie replacement for a
freebie scanner which now works OK, we didn't lose any sleep over
it's lack of performance.
Thanks for the reply,
Al

Hi Alan,
So many people messing with underpowered plotters, I
just had to remedy the problem. Everytime I had it done I
found a way to make it cheaper. I would be nice to find a really
simple and cheap way to make PCBoards. I mean fast and cheap!


John

--- In Homebrew_PCBs@y..., Alan Marconett KM6VV <KM6VV@a...> wrote:
> Hi John,
>
> Saw your site. Nice implementation on Morph!
>
> Alan KM6VV
>
> crankorgan wrote:
> >
> > Hi Alan,
> > Yes using a spinning scribe would make a wider path. I
> > have an animation on my webpage. Let it load and you will see
> > a pic of each side of the machine. One guy built a clone of the
> > Morph by just looking at the pics.
> >
> > John
> >
> > --- In Homebrew_PCBs@y..., Alan Marconett KM6VV <KM6VV@a...>
wrote:
> > > Hi John,
> > >
> > > What about a small rotating burnishing tool, so the "scratches"
> > would
> > > have some width? I can see that this would be very similar to
> > milling
> > > the isolation traces.
> > >
> > > Alan KM6VV
> > > P.S. Heard you've got a new mill/plotter working? pix?
> > >

Not all the printers I've looked at had head cover cups.

Changing cartridges is why I like the Lexmarks so well for this application. The ink and head is built together. Drop in the
ink head for a test plot, drop in the resist head for a board plot.

later,
Larry E.

----- Original Message -----
From: Steve G
To: Homebrew_PCBs@yahoogroups.com
Sent: Saturday, September 14, 2002 9:37 PM
Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards


--- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...> wrote:
I think all inkjet printers have that rubber cup. The holder for HP
and Canon print heads has the rubber cup.


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

I've given you a fast and CHEAP method!

Fill an inkjet printer cartridge with Future or other brand acrylic floor polish! Print that to
the board, then etch away! After it's etched, wipe it off with ammonia!

If you get .014 thick single sided PC board blanks they will feed through all the printers
I mentioned without modification. If you want to do doubled sided boards, you'll have to
remove the printer mechanism and change the platen roller to a linear Y axis to move the
length of the PC board laying on a plotting table.

An easy ( and cheap ) way to do this is first calculate the gear ratio of the stepper to the platen
roller. Then put a simple pulley on each end of the plotter. Attach a wire 'cable' loop around these
pulleys and attach the printer mechanism to that cable. Of course the printer mechanism is riding
on two standard linear rails. ( polished shafts and bronze bearings ).

The Lexmark I first used needed more gear reduction than a single pulley could provide so I used
a microcontroller to catch the phase steps to the micro and output a reduced set of steps to the
original stepper motor. I used a 16F628 PIC and an L298 for this. The steps ratio was adjusted via
a serial connection to a PC.

I was able to modify an Epson 1520 wide carriage printer to feed a standard .062 board through but
that didn't solve the double sided problem. The only way I found to do that is convert the printer to a
flatbed arrangement. The nice thing about the Lexmark and cheap Epsons I looked at is the power
supply and all electronics are on a PC board that's mounted to the mechanism. Take it out of the
plastic and you've got a nice small "rail" to mount on your Y axis linear rail. The only cables you
need to connect were the wall wart and USB cable.

Oh, there is an issue with the "out of paper switch" that some printers pull a sheet of paper in until
it hits a switch or optical sensor then they back it out to a preset location. I was able to get around
this with the same gear reduction microcontroller. I just used the "paper" switch for a "home" switch
and that let the mechanism return to 'home' between each run. A manual "run" switch served as
"paper out" so you had to flip this switch after you got a board blank on the bed. That lets you easily
plot one side, flip the switch when it's returning home, flip the board over, flip the switch again and
let it plot the other side.

By the way, the floor polish works well in plotter pens for etchant resist also.

I can't take credit for the thought of using acrylic floor polish for etchant resist. Evidently artists that do
copper plate art stamping have been using it for years.

I also left a board with .020 traces in ammonium persulfate for a week to see if the acrylic would stand up to it. It worked
great. However, I did the same thing with some .005 wide traces and the etchant undercut the traces and it
all floated away.

You could also use floor polish for scratch and etch resist but you'll need to color it with something to easily
see it. I do think the machinist blue is best for this approach.

The machineist blue is a nitrocellulose base with several alcohols for solvent. It drys too quick to use in an inkjet
in case some is thinking of trying that. ( been there, done that, clogged up the cartridge). It doesn't work all that
well in a plotter pen either.

Oh, I almost forgot, you'll also need another board to lift the PC board blank surface up towards the inkjet head.
What I did is measured the distance between the paper and the platen roller on the existing printer, then cut
a piece of MDF to thickness with a wood planer. Just subtract the thickness of the PC board blank you plan
on using from the needed thickness. You could automate this with some screws a stepper and a belt on your
Y linear rail attachment points to make it work with varying thickness PC board stock.

later,
Larry E.

----- Original Message -----
From: crankorgan
To: Homebrew_PCBs@yahoogroups.com
Sent: Sunday, September 15, 2002 3:56 PM
Subject: [Homebrew_PCBs] Re: Inkjet printing PC boards


Hi Alan,
So many people messing with underpowered plotters, I
just had to remedy the problem. Everytime I had it done I
found a way to make it cheaper. I would be nice to find a really
simple and cheap way to make PCBoards. I mean fast and cheap!


John



--- In Homebrew_PCBs@y..., Alan Marconett KM6VV <KM6VV@a...> wrote:
> Hi John,
>
> Saw your site. Nice implementation on Morph!
>
> Alan KM6VV
>
> crankorgan wrote:
> >
> > Hi Alan,
> > Yes using a spinning scribe would make a wider path. I
> > have an animation on my webpage. Let it load and you will see
> > a pic of each side of the machine. One guy built a clone of the
> > Morph by just looking at the pics.
> >
> > John
> >
> > --- In Homebrew_PCBs@y..., Alan Marconett KM6VV <KM6VV@a...>
wrote:
> > > Hi John,
> > >
> > > What about a small rotating burnishing tool, so the "scratches"
> > would
> > > have some width? I can see that this would be very similar to
> > milling
> > > the isolation traces.
> > >
> > > Alan KM6VV
> > > P.S. Heard you've got a new mill/plotter working? pix?
> > >


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

I killed an Epson printhead that got clogged with Schellac by forcing alcohol through it with a syringe.

I've heard of others getting away with it though.

later,
Larry E.

----- Original Message -----
From: Steve Greenfield
To: Homebrew_PCBs@yahoogroups.com
Sent: Sunday, September 15, 2002 1:01 AM
Subject: Re: [Homebrew_PCBs] Re: Lexmark help, (was Inkjet printing PC boards)


One of the reasons I don't want to risk my BJC 6000 is because
print heads are very delicate.


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

Buy a new printer and use that one for you PC board printer doner?
Take the color cartridge out and store it in a baggie with some windex in it?
Refill the cartridge with a useable amount of ink?

later,
Larry E.

----- Original Message -----
From: alenz2002
To: Homebrew_PCBs@yahoogroups.com
Sent: Sunday, September 15, 2002 12:19 AM
Subject: [Homebrew_PCBs] Re: Lexmark help, (was Inkjet printing PC boards)


Hi Larry and Steve,

This is OT but I have a problem that I think you might be able to
help with. My wife has a Lexmark printer that the color cartridge only
lasts for one print session and then dries up. The black will last
until it runs out of ink. Of course at $20+ per cart, she doesn't
use color. Based on your comments, it seems like the color cart
doesn't sit properly on the rubber cup, (I didn't even know about
the rubber cups til now). I see what you are talking about, looks
sorta look like an empty IC socket. Spring loaded, both seem free
to move up and down. But I can't see what they look like when the
heads are parked. Do they move down while the head is traveling
and then move up? Would a few drops of some sort of solvent in the
cups help?
Also, is there any way to restore a cart with a dried head, but should
still be full of ink? I just now tried scrubbing one with a Q-tip
and water, (have tried alcohol, etc.) Was able to get yellow, red
and blue ink to flow out onto a paper towel, but it wouldn't print.
She ran 15 sheets thru in the test/clean mode and it spit and
sputtered all colors, but not usable. Any advice is greatly
appreciated.

Thanks in advance,
Al Lenz
P.S. Yes Steve this is a really GREAT group. I have used several of
the ideas presented here with success.
al

--- In Homebrew_PCBs@y..., "Steve G" <alienrelics@y...> wrote:
> --- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...> wrote:
> > No, I didn't look at any of the Canon printers.
> >
> > The Lexmark however has an even better solution than changing
heads.
> >
> > It has a rubber cup the head sits down on when the head is parked
> to prevent drying.

<snip>
> I think all inkjet printers have that rubber cup. The holder for HP
> and Canon print heads has the rubber cup.

<snip>



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

I thought they all had head cups. They have to have something to
seal the head, but of course if it isn't a cup you can't put
anything in it to keep the head from clogging.

I just remembered I have a couple of HP Deskjet 320 with very
straight paper path. It is a laptop sized inkjet, one of those
annoying ones with one space for a head, you have to swap to a CMY
cart to print color. The HPs have the head and ink in one, too. I
have an empty cart although it is pretty crusted up. Since you have
to swap the color and black carts, it comes with a holder.

It won't take anything very thick although it doesn't seem to have
a problem with thick card stock, but might accept some of the
really thin PCB stock I have.

Steve Greenfield

--- Larry Edington <ledington@...> wrote:

> Not all the printers I've looked at had head cover cups.
>
> Changing cartridges is why I like the Lexmarks so well for this
> application. The ink and head is built together. Drop in the
> ink head for a test plot, drop in the resist head for a board
> plot.
>
> later,
> Larry E.

=====
Steve Greenfield // Digital photo scanning, retouching,
Polymorph Digital Photography // and photomorphing to your specs.
253/318-2473 voice // We use the best little computer in
polymorph@... // the world, the Amiga!
http://www.polyphoto.com/ // Based in Tacoma, WA, USA

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Did anyone ever try the "plain paper" FAX machine?

The film they use is a wax based, black compound that is very
visible. You could (theoretically) print to a PCB without any
computers being involved.

I don't have one of these fax machines, but you could probably pick
one up for next to nothing at a used crap (reuse) centre. I saw one a
while back, so I will go back to see if they have another one.
There is many of them babies around.

John M...
==================