Homebrew_PCBs

HI all
ETCH TANK'S
I have used corn flaks containers from the hard ware store these have a
sealed lid to keep continence dry made of white polythene and are made by tupper ware they make
good vertical tanks for etching and developing
AIR AGITATION
A fish tank air pump feeding a plastic pipe with small holes drilled
in it for air agitation
As the fish tank air blocks quickly get blocked up
PCB HOLDERS
plastic netting is easy cut with seisers and folded in half will make a
good support for dipping Bord's in the etch Barth if you weave plastic
rod's[large plastic knitting needles] in the plastic netting you have
support Handel's to lift in and out of tank.
TANK HEATING
fish tank Emerson heater to keep tempter constant most have adjustable thermostat for temptcher control


Jest my two pence worth
Captin vidio
Fist post to grope been reading for a while







---------------------------------
Yahoo! Messenger - Communicate instantly..."Ping" your friends today! Download Messenger Now

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

That's not a bad solution at all. What's the capacity of the tank
(both in terms of etchant and size of PCB)? I couldn't find anything
that held 1 L (or quart), would etch a 6"X6" board and was at least
8" deep (to hold the tank heater). They usually held 2 or 4 quarts
and I didn't want to have that much etchant at a time.

For me, that forced the inside dimensions of the liquid volume to be
8x7x1.25. The heater and air tube displaces enough to take it under
a liter.

By the way, Circuit Specialists has a kit that looks good for $40.
It includes the tank, heater and air pump. http://www.web-
tronics.com/lowcosetsysw.html If I were to do it over, I'd probably
buy it instead of make my own. I spent about $30 on mine and took a
few hours to do it. I dont believe their 4 minute etch time claim
though...


--- In Homebrew_PCBs@yahoogroups.com, steve muirfield
<smuifield@y...> wrote:

> HI all
> ETCH TANK'S
> I have used corn flaks containers from the hard ware store these

have a

> sealed lid to keep continence dry made of white polythene and are

made by tupper ware they make

> good vertical tanks for etching and developing
> AIR AGITATION
> A fish tank air pump feeding a plastic pipe with small holes

drilled

> in it for air agitation
> As the fish tank air blocks quickly get blocked up
> PCB HOLDERS
> plastic netting is easy cut with seisers and folded in half will

make a

> good support for dipping Bord's in the etch Barth if you weave

plastic

> rod's[large plastic knitting needles] in the plastic netting you

have

> support Handel's to lift in and out of tank.
> TANK HEATING
> fish tank Emerson heater to keep tempter constant most have

adjustable thermostat for temptcher control

>
>
> Jest my two pence worth
> Captin vidio
> Fist post to grope been reading for a while
>
>
>
>
>
>
>
> ---------------------------------
> Yahoo! Messenger - Communicate instantly..."Ping" your friends

today! Download Messenger Now

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

oops, sorry about the URL - here it is again.
<http://www.web-tronics.com/lowcosetsysw.html>

--- In Homebrew_PCBs@yahoogroups.com, "Phil" <phil1960us@y...> wrote:
> That's not a bad solution at all. What's the capacity of the tank
> (both in terms of etchant and size of PCB)? I couldn't find
anything
> that held 1 L (or quart), would etch a 6"X6" board and was at least
> 8" deep (to hold the tank heater). They usually held 2 or 4 quarts
> and I didn't want to have that much etchant at a time.
>
> For me, that forced the inside dimensions of the liquid volume to
be
> 8x7x1.25. The heater and air tube displaces enough to take it
under
> a liter.
>
> By the way, Circuit Specialists has a kit that looks good for $40.
> It includes the tank, heater and air pump. http://www.web-
> tronics.com/lowcosetsysw.html If I were to do it over, I'd
probably
> buy it instead of make my own. I spent about $30 on mine and took
a
> few hours to do it. I dont believe their 4 minute etch time claim
> though...
>
>
> --- In Homebrew_PCBs@yahoogroups.com, steve muirfield
> <smuifield@y...> wrote:
> > HI all
> > ETCH TANK'S
> > I have used corn flaks containers from the hard ware store these
> have a
> > sealed lid to keep continence dry made of white polythene and are
> made by tupper ware they make
> > good vertical tanks for etching and developing
> > AIR AGITATION
> > A fish tank air pump feeding a plastic pipe with small holes
> drilled
> > in it for air agitation
> > As the fish tank air blocks quickly get blocked up
> > PCB HOLDERS
> > plastic netting is easy cut with seisers and folded in half will
> make a
> > good support for dipping Bord's in the etch Barth if you weave
> plastic
> > rod's[large plastic knitting needles] in the plastic netting you
> have
> > support Handel's to lift in and out of tank.
> > TANK HEATING
> > fish tank Emerson heater to keep tempter constant most have
> adjustable thermostat for temptcher control
> >
> >
> > Jest my two pence worth
> > Captin vidio
> > Fist post to grope been reading for a while
> >
> >
> >
> >
> >
> >
> >
> > ---------------------------------
> > Yahoo! Messenger - Communicate instantly..."Ping" your friends
> today! Download Messenger Now
> >
> > [Non-text portions of this message have been removed]

On Sat, 10 Apr 2004 18:44:41 -0000, Phil <phil1960us@...> wrote:

> That's not a bad solution at all. What's the capacity of the tank
> (both in terms of etchant and size of PCB)? I couldn't find anything
> that held 1 L (or quart), would etch a 6"X6" board and was at least
> 8" deep (to hold the tank heater). They usually held 2 or 4 quarts
> and I didn't want to have that much etchant at a time.
>
> For me, that forced the inside dimensions of the liquid volume to be
> 8x7x1.25. The heater and air tube displaces enough to take it under
> a liter.
>
> By the way, Circuit Specialists has a kit that looks good for $40.
> It includes the tank, heater and air pump. http://www.web-
> tronics.com/lowcosetsysw.html If I were to do it over, I'd probably
> buy it instead of make my own. I spent about $30 on mine and took a
> few hours to do it. I dont believe their 4 minute etch time claim
> though...
>

I consider making one of glass...
I would get the glass for free, plexiglass not.
I reckon gluing with silicone glue on both sides would be a good idea.

It would be placed inside another container which could hold everything
if there is a leak or breaking.

The lid would be made of plexiglass.
I guess a bead of silicone, then a piece of thin plastic, then press the
lid on to form a good seal.

Thanks for all the suggestions about he tank, but most
of them are not exactly what i want to do.
i want the perfect tank (like always) with no mess, no "dead" space on the
pcb due to covering by clamps, no touching of immersed parts while
loading/unloading,
maximum of possible area possible, fully adjustable to all sizes.

Like always i try to make the impossible.....

ST

P.S.: haven't told you about the hot air pencil i tried to build.
the damn heating element was defunct and i had a little tabletop fire..
but gladly i plugged it at the isolation transformer so no harm done.
I tried to use an old soldering iron, should have tested it before.

Will make a new one when there is time, but different, a small copy of the
heat gun i have using a ceramic heating chamber which holds the heating
wire
and provides enough surface area. this time i will aim for a 50V unit so
that
no proper isolation is required. i can make a simple temperature control
circuit
with a thermistor and a scr.
still have to look if i can find a proper ceramic body to hold the wire, i
guess
a old "radiation heater" will do the job, chop of a bit of the ceramic
element.
, or maybe just a number of those small cermic isolation beads will do....

I hope to end up with something that is a bit better suited for small smd
work,
the steinel gun is very nice a tool and i use it often but it is cumbersome
and heavy to use for small things.

Hi-
Thanks for the link, they have several:
*Low Cost PCB Etching System(416ES)
<http://www.web-tronics.com/lowcospcbets.html> - no heater
**LOW COST ETCHING SYSTEM w AGITATOR & HEATER (ET10)
<http://www.web-tronics.com/lowcosetsysw.html> -- looks like best one
**Low Cost Etching Tank System w Agitator & Heater(12-700)
<http://www.web-tronics.com/lowcosettans.html> - similar to last
*David


Phil wrote:

>That's not a bad solution at all. What's the capacity of the tank
>(both in terms of etchant and size of PCB)? I couldn't find anything
>that held 1 L (or quart), would etch a 6"X6" board and was at least
>8" deep (to hold the tank heater). They usually held 2 or 4 quarts
>and I didn't want to have that much etchant at a time.
>
>For me, that forced the inside dimensions of the liquid volume to be
>8x7x1.25. The heater and air tube displaces enough to take it under
>a liter.
>
>By the way, Circuit Specialists has a kit that looks good for $40.
>It includes the tank, heater and air pump. http://www.web-
>tronics.com/lowcosetsysw.html If I were to do it over, I'd probably
>buy it instead of make my own. I spent about $30 on mine and took a
>few hours to do it. I dont believe their 4 minute etch time claim
>though...
>
>
>--- In Homebrew_PCBs@yahoogroups.com, steve muirfield
><smuifield@y...> wrote:
>
>
>>HI all
>>ETCH TANK'S
>>I have used corn flaks containers from the hard ware store these
>>
>>
>have a
>
>
>>sealed lid to keep continence dry made of white polythene and are
>>
>>
>made by tupper ware they make
>
>
>>good vertical tanks for etching and developing
>>AIR AGITATION
>>A fish tank air pump feeding a plastic pipe with small holes
>>
>>
>drilled
>
>
>>in it for air agitation
>>As the fish tank air blocks quickly get blocked up
>>PCB HOLDERS
>>plastic netting is easy cut with seisers and folded in half will
>>
>>
>make a
>
>
>>good support for dipping Bord's in the etch Barth if you weave
>>
>>
>plastic
>
>
>>rod's[large plastic knitting needles] in the plastic netting you
>>
>>
>have
>
>
>>support Handel's to lift in and out of tank.
>>TANK HEATING
>>fish tank Emerson heater to keep tempter constant most have
>>
>>
>adjustable thermostat for temptcher control
>
>
>>
>>Jest my two pence worth
>>Captin vidio
>>Fist post to grope been reading for a while
>>
>>
>>
>>
>>
>>
>>
>>---------------------------------
>> Yahoo! Messenger - Communicate instantly..."Ping" your friends
>>
>>
>today! Download Messenger Now
>
>
>>[Non-text portions of this message have been removed]
>>
>>
>
>
>
>
>Be sure to visit the group home and check for new Bookmarks and files:
>http://groups.yahoo.com/group/Homebrew_PCBs
>Yahoo! Groups Links
>
>
>
>
>
>
>
>

I use a Cooler, Holds 12L, I fill it with 8L. I use a 150 Watt fully
submersible heater on the bottom of the tank, resting on a piece of sealed
PVC filled with rocks, with two -re drilled bubble walls on either side.
I'm in the process of creating holders from - plastic light cover grid , As
it is right now, I generally loose my board in the tank and have to go
fishing.

Looks like this, only red, cost about $13 at Target, (i use 1 for mask
stripper, and 1 for etch)
http://makeashorterlink.com/?D14722DF7


JT
http://www.soundclick.com/jtsound

----- Original Message -----
From: "Phil" <phil1960us@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Saturday, April 10, 2004 2:49 PM
Subject: [Homebrew_PCBs] Re: ETCH TANK'S [COST EFFTIVE]


> oops, sorry about the URL - here it is again.
> <http://www.web-tronics.com/lowcosetsysw.html>
>
> --- In Homebrew_PCBs@yahoogroups.com, "Phil" <phil1960us@y...> wrote:
> > That's not a bad solution at all. What's the capacity of the tank
> > (both in terms of etchant and size of PCB)? I couldn't find
> anything
> > that held 1 L (or quart), would etch a 6"X6" board and was at least
> > 8" deep (to hold the tank heater). They usually held 2 or 4 quarts
> > and I didn't want to have that much etchant at a time.
> >
> > For me, that forced the inside dimensions of the liquid volume to
> be
> > 8x7x1.25. The heater and air tube displaces enough to take it
> under
> > a liter.
> >
> > By the way, Circuit Specialists has a kit that looks good for $40.
> > It includes the tank, heater and air pump. http://www.web-
> > tronics.com/lowcosetsysw.html If I were to do it over, I'd
> probably
> > buy it instead of make my own. I spent about $30 on mine and took
> a
> > few hours to do it. I dont believe their 4 minute etch time claim
> > though...
> >
> >
> > --- In Homebrew_PCBs@yahoogroups.com, steve muirfield
> > <smuifield@y...> wrote:
> > > HI all
> > > ETCH TANK'S
> > > I have used corn flaks containers from the hard ware store these
> > have a
> > > sealed lid to keep continence dry made of white polythene and are
> > made by tupper ware they make
> > > good vertical tanks for etching and developing
> > > AIR AGITATION
> > > A fish tank air pump feeding a plastic pipe with small holes
> > drilled
> > > in it for air agitation
> > > As the fish tank air blocks quickly get blocked up
> > > PCB HOLDERS
> > > plastic netting is easy cut with seisers and folded in half will
> > make a
> > > good support for dipping Bord's in the etch Barth if you weave
> > plastic
> > > rod's[large plastic knitting needles] in the plastic netting you
> > have
> > > support Handel's to lift in and out of tank.
> > > TANK HEATING
> > > fish tank Emerson heater to keep tempter constant most have
> > adjustable thermostat for temptcher control
> > >
> > >
> > > Jest my two pence worth
> > > Captin vidio
> > > Fist post to grope been reading for a while
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > ---------------------------------
> > > Yahoo! Messenger - Communicate instantly..."Ping" your friends
> > today! Download Messenger Now
> > >
> > > [Non-text portions of this message have been removed]
>
>
>
>
> Be sure to visit the group home and check for new Bookmarks and files:
> http://groups.yahoo.com/group/Homebrew_PCBs
> Yahoo! Groups Links
>
>
>
>
>

I was in The Container Store today. They had a few suitable items. One
was a magazine slipcover.
A collector's box for cereal boxes would be a nice fit too.

I believe I saw someone on the internet was using a foot bath to
agitate their solution. I believe the
tank was mounted on top. The aquarium bubbler is probably a better
solution though.

Regards,
JJ

On Saturday, Apr 10, 2004, at 15:44 US/Eastern, Jeremy Taylor wrote:

> I use a Cooler, Holds 12L, I fill it with 8L. I use a 150 Watt fully
> submersible heater on the bottom of the tank, resting on a piece of
> sealed
> PVC filled with rocks, with two -re drilled bubble walls on either
> side.
> I'm in the process of creating holders from - plastic light cover
> grid , As
> it is right now, I generally loose my board in the tank and have to go
> fishing.
>
> Looks like this, only red, cost about $13 at Target, (i use 1 for mask
> stripper, and 1 for etch)
> http://makeashorterlink.com/?D14722DF7
>
>
> JT
> http://www.soundclick.com/jtsound
> ----- Original Message -----
> From: "Phil" <phil1960us@...>
> To: <Homebrew_PCBs@yahoogroups.com>
> Sent: Saturday, April 10, 2004 2:49 PM
> Subject: [Homebrew_PCBs] Re: ETCH TANK'S [COST EFFTIVE]
>
>
>> oops, sorry about the URL - here it is again.
>> <http://www.web-tronics.com/lowcosetsysw.html>
>>
>> --- In Homebrew_PCBs@yahoogroups.com, "Phil" <phil1960us@y...> wrote:
>>> That's not a bad solution at all. What's the capacity of the tank
>>> (both in terms of etchant and size of PCB)? I couldn't find
>> anything
>>> that held 1 L (or quart), would etch a 6"X6" board and was at least
>>> 8" deep (to hold the tank heater). They usually held 2 or 4 quarts
>>> and I didn't want to have that much etchant at a time.
>>>
>>> For me, that forced the inside dimensions of the liquid volume to
>> be
>>> 8x7x1.25. The heater and air tube displaces enough to take it
>> under
>>> a liter.
>>>
>>> By the way, Circuit Specialists has a kit that looks good for $40.
>>> It includes the tank, heater and air pump. http://www.web-
>>> tronics.com/lowcosetsysw.html If I were to do it over, I'd
>> probably
>>> buy it instead of make my own. I spent about $30 on mine and took
>> a
>>> few hours to do it. I dont believe their 4 minute etch time claim
>>> though...
>>>
>>>
>>> --- In Homebrew_PCBs@yahoogroups.com, steve muirfield
>>> <smuifield@y...> wrote:
>>>> HI all
>>>> ETCH TANK'S
>>>> I have used corn flaks containers from the hard ware store these
>>> have a
>>>> sealed lid to keep continence dry made of white polythene and are
>>> made by tupper ware they make
>>>> good vertical tanks for etching and developing
>>>> AIR AGITATION
>>>> A fish tank air pump feeding a plastic pipe with small holes
>>> drilled
>>>> in it for air agitation
>>>> As the fish tank air blocks quickly get blocked up
>>>> PCB HOLDERS
>>>> plastic netting is easy cut with seisers and folded in half will
>>> make a
>>>> good support for dipping Bord's in the etch Barth if you weave
>>> plastic
>>>> rod's[large plastic knitting needles] in the plastic netting you
>>> have
>>>> support Handel's to lift in and out of tank.
>>>> TANK HEATING
>>>> fish tank Emerson heater to keep tempter constant most have
>>> adjustable thermostat for temptcher control
>>>>
>>>>
>>>> Jest my two pence worth
>>>> Captin vidio
>>>> Fist post to grope been reading for a while
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> ---------------------------------
>>>> Yahoo! Messenger - Communicate instantly..."Ping" your friends
>>> today! Download Messenger Now
>>>>
>>>> [Non-text portions of this message have been removed]
>>
>>
>>
>>
>> Be sure to visit the group home and check for new Bookmarks and files:
>> http://groups.yahoo.com/group/Homebrew_PCBs
>> Yahoo! Groups Links
>>
>>
>>
>>
>>
>
>
>
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I went out yesterday to Staples and got a letter sized Rubbermaid
hanging folder holder, and to a pet shop and got an air pump, heater,
hose and air stone. It sound like I should return the air stone and
just pierce the tubing a bunch to let the air out, instead. The
rubbermaid thing is about 13 x 9 x 4, internal, with a lip around the
inside for hanging folders (or pcb holders). It has a hinged top (the
hinge is just a fold between the top bottom) that snaps on, and a
carrier handle that 'locks' the top down. It's marked with 5 in the
recycle symbol, and PP. I'm assuming that its poly propylene. I have a
plastic pail in the garage with a snap on top that came holding bulk cat
litter, but it looks like 2.5 gallons or so, and has no easy to use
places for hanging board holders. I have some 1.25 inch, 80 psi sewer
pipe, which is black, not white. I don't know the chemistry. I was
thinking about slicing it down one side so I can just shove the edge of
the board in there, like an upside down flag, and just put it in the
etchant with the long end sticking out.
I got 2 gallons of hcl for $5 at home despot, and a quart of h2o2 for
a buck at Savon. Now all I have to do is use the stuff.
Does anyone know of any limitations on etching chemistries for
different types of plastic?
I've looked around some, and never seen any sites that say 'use 5
parts hcl to 1 part h2o2 to 9 parts h2o', or whatever. Does anyone know
what the final % hcl and h2o2 the solution should start with? I've seen
how to keep the cucl2 going, but not how to start it right.
Thanks,
Richard

Oh, yeah!?! well here is MY next etch tank. Built in recirc pump
and bubbler and includes a custom cover. I can do a a 7'x7' board in
it. Anyone know a good bulk source of HCl and H2O2? I'd guess I'll
need about 250 Gals of each...

http://jacuzzipremium.com/SpaShowroom/Spas/J385.shtml

> places for hanging board holders. I have some 1.25 inch, 80 psi

sewer

> pipe, which is black, not white. I don't know the chemistry. I

White sewer pipe is PVC plastic, the black stuff is ABS, butI don't
know anything about it's chemical reactivity.

> I got 2 gallons of hcl for $5 at home despot, and a quart of h2o2

for

> a buck at Savon. Now all I have to do is use the stuff.

I'm guessing, but is that Savon drug store? So this H2O2 is the 3%
medical grade?

> I've looked around some, and never seen any sites that say 'use 5
> parts hcl to 1 part h2o2 to 9 parts h2o', or whatever. Does anyone

know

> what the final % hcl and h2o2 the solution should start with? I've

seen

> how to keep the cucl2 going, but not how to start it right.
> Thanks,
> Richard

Others will reccomend using stronger H2O2, 30% or 50%. But I had a
hard time finding it without paying extremly high hazmat delivery
fees, so I experimented with using the weaker medical grade.

My acid (HLC, or Muratic) is bottled at 31 point something percent
strength. From what I've read you want between 10 and 15% in the
final etchant. Generaly that's accomplished by diluting the acid 50-
50 with water and then adding up to a couple ounces per gallon of 30%
H2O2.

I have successfully used 2 parts 3% medical H2O2 with one part 31%
acid - no additional water. It's pretty close to the same mix when
you're done. Etching times of 7-10 minutes.

With stronger H2O2 (30% or more) you can just add a little more to
regenerate the mix. With the 3% stuff it has too much water and if
you add enough to regenerate the CuCl it dilutes the mix to much. To
get around that I usualy just regenerate with a bubbler. (aquarium
pump and a plastic "air stone")

By the way, I use a rubbermaid 5161 ceareal keeper as an etch tank:
http://tinyurl.com/3hbax About $5.50 at Walmart, holds a gallon and a
half and can do a 9x9 inch board nicely. For a holder I usualy just
dangle them on a piece of plastic coated wire (cat5). Mostly just
loose loops around opposite corners, but sometimes I drill a hole in
the corner.

-Denny

Phil
I think you forgot to mention that there is a built in heater! Don't
show that around too much, it will take away the manufacturing edge you
just got! I hear you can get good deals on hcl and h202 in 55 gal.
increments, plus it comes in containers that make great project boxes
(at least for the projects I have to throw away).
Denny
The HCL is a little less than 30%, and yes, Savon Drugs & 3% on the
h2o2. I appreciate the help with the final % and ratios. I guess I'll
just go ahead and try the PP and ABS and hope it doesn't eat through
them. I still have to find a place to generate toner images for TT
(I've got 2 ink jets, no laser), I guess I'll just print it and then
copy it at work. I just gutted an old (85 manufacture date) copier, and
pulled the motor, fuser and some other parts, to make my own laminator.
That monster must have weighted over 100 pounds. I was just going to
throw it away, but it was way too heavy for me to carry downstairs and
to the dumpster, so I decided to field strip it in place and scavenge
what I could.
Mike
From what I've read on CuCl2 etching, there are a few things that
cause chlorine generation. Two of them: not enough copper, and too much
copper. When you are just starting with hcl&h2o2, you are way in to the
one regime. You need regime change, and only use, or dumping copper
into it will get you into the stable regime. In this case, application
of power, lead or unstable nitrates won't lead to regime change. ;^)
Thanks all,
Richard
Please don't take my 'regime change' comments as political comments, it
really just came out that way <G>. (Though I'm usually willing to argue
politics off line)

> Denny
> The HCL is a little less than 30%, and yes, Savon Drugs & 3% on

the

> h2o2. I appreciate the help with the final % and ratios. I guess

Just to point out, the 3% will work, but it's too weak for long term
use to regenerate.

<snip>

> From what I've read on CuCl2 etching, there are a few things that
> cause chlorine generation. Two of them: not enough copper, and too

much

Well, that may be true, but from my experiance it isn't. From my
experiance the sure way to generate lots of chlorine is to put in too
much H2O2. The extra oxygen bonds with the hydrogen in the HCL to
make water and in the proccess it frees pleanty of chlorine.

Since I don't use H2O2 to regenerate, I haven't seen this issue since
I mixed it up to start with.

-Denny

What effect has heating on CuCl etchants?

Both, H2O2 and air regenerated are interesting to know.

i would assume it may be faster, but have no idea if it will also
encourage gassing if using H2O2.

thanks

ST

> Just to point out, the 3% will work, but it's too weak for long term
> use to regenerate.

<snip>>

> Well, that may be true, but from my experiance it isn't. From my
> experiance the sure way to generate lots of chlorine is to put in too
> much H2O2. The extra oxygen bonds with the hydrogen in the HCL to
> make water and in the proccess it frees pleanty of chlorine.
>
> Since I don't use H2O2 to regenerate, I haven't seen this issue since
> I mixed it up to start with.
>
> -Denny

Denny
OK, with my 3% h2o2, sounds like outgasing won't be an issue, just
over dilution. It is also my intention to, post-etch, bubble it back
to life, then store it, maybe keeping some h2o2 for when I really need it.
Thanks
Richard

Hi all,

just discovered foam rubber is great for rubbing paper residue off, really
fast and doesn't damage
the toner. it also gets out the paper of the holes much faster than thumb
rubbing.

the foam brings down the wite residue to a level where i would accept it
as component outline
without clear-laquer coating.


the 6,66mil traces also work quite well but i definitely need a better
printer.

ST

again, sorry for messing up with the adresses and the flooding now...

last message..
ST


hi..

for those interested i have put a picture of a 6 mil board i just made on
<http://stud4.tuwien.ac.at/~e0225977/pcb.jpg>


the black particles you see is toner residue, i have only scraped it off
not cleaned
with paint thinner.
i find it quite easy and fast to just scrape if off with another bard, the
HP toner
is brittle enough to make this work.


you can also see a pinhole, which i regularly get with this printer.
normally i fill them with ohp pen, if i see them.

i also find the staedtler pen does not very well resist the cucl if it
gets older,
i wonder if there is a better solution.
my suspicion is that the layer gets thinner as the pen gets older and
dryer, but refilling
didn't change the effect. i hope they have not changed the recepie as some
old texts say.

i could reduce the spacing to about 10 mil, maybe 8 (with testing), but
there was plenty of space on this board.

I'm really satisfied now with the TT, and the etch (there is no gassing if
you don't have too much
H2O2, just keep it nice and green).


the main problem which really annoys me is the problems with the metric
spacing effects and
of course the pinholes which i just can't get rid of with that printer.
maybe thinner paper would
improove the situation a bit.


so now i am looking for a new printer. hopefully one that makes no
pinholes.
the bad thing with a new printer is that the toner is so expensive, 7 eur
for a genuine cartridge
at ebay for the IIID is hard to beat.


another big problem is doublesided boards. i try to avoid them but
sometimes there is no way.
the aligning is something i hate, and the fusing is also more difficult.
i think more practise would help with this.

I've made quite a few boards the last week, which allowed a steep learning
curve.
If you make only a board a month you forget what you have done the last
time until the next time.

I notice yahoo is slow again, damn it...
thanks for all the help...

ST

well, nobody seems to have an idea so i did a small experimant.

used 2 glass containers, same size, etchant, same amount in both from the
same batch.
then 2 samples of pcb, you guess it, identical.

heated some water and put one glass in it.
bad thing didn't check boiling point of HCl before --> nasty HCl fumes.
the temperature of the water was 60degree C. boiling point of HCl is
around 50C.
after i have found that out i diluted the heating bath to 45C. (about
halfway
through the etch)

the etching was of course much faster, 15min or so (without adding any
H2O2,
the etchant was regenerated 2 days ago and 1 pcb etched, still light
green).
now it is about 40 minutes and the cold etchant only starts to show the
edges come off...

You see it is really much faster but the HCl fumes are BAD.
i will try again, maybe with 40C or so.

If the process can be accelerated without the fumes it would certainly be
interesting.

any discussion welcome..

ST

>
> What effect has heating on CuCl etchants?
>
> Both, H2O2 and air regenerated are interesting to know.
>
> i would assume it may be faster, but have no idea if it will also
> encourage gassing if using H2O2.
>
> thanks
>
> ST

<http://www.turi.org/publications/rep45.htm>

also a few lines on chemical regeneration.

discussion welcome on how and if one could build a electrolytical system.

ST

They use an ion exchange membrane in the regeneration cell. I'm
not exactly sure what the membrane is doing in this situation.
Obviously its separating ions from anode to cathode.
Unfortunately the image showing the electrolytic cell is missing
from the web page. I'm sure PVC membranes can be purchased but I
figure the control system necessary to make this work would be
prohibitively complicated for a hobby. I'm not saying it couldn't
be done, but attempting to build such a system could end up being
a whole hobby in itself.

I have build the basics of a electro generative tank for alkaline
ammonia sulfate, but this enchant is only suitable for metal
plated etch resist, i.e tin or tin/lead plated tracks. The high
pH 9.0 ~ 10.0 of this enchant means it attacks standard
photoresists in just seconds. If you also wanted to make a tin
plating tank too then this enchant is excellent. Its about same
speed as air regenerated CuCl (bubble etch 25 minutes for "1 oz"
copper at 25°C). The problem is it smells of ammonia so it must
be in sealed tank, with small opening for the PCB. If bubbles are
passed through it then you must use recirculating air pump.

I don't think there is simple method to electrolytically
regenerate etchants. The alkaline ammonia is the simplest etchant
to regenerate electrolytically but its drawbacks are ammonia
smell and it limited to metal plating resists.

Here is another short article on etchant regeneration.
http://www.circuitree.com/CDA/ArticleInformation/features/BNP__Features__Item/0,2133,97639,00.html


Stefan Trethan wrote:

> <http://www.turi.org/publications/rep45.htm>
>
> also a few lines on chemical regeneration.
>
> discussion welcome on how and if one could build a electrolytical system.
>
> ST
>

On Fri, 16 Apr 2004 10:22:49 +1000, Adam Seychell
<adam_seychell@...> wrote:

> They use an ion exchange membrane in the regeneration cell. I'm
> not exactly sure what the membrane is doing in this situation.
> Obviously its separating ions from anode to cathode.
> Unfortunately the image showing the electrolytic cell is missing
> from the web page. I'm sure PVC membranes can be purchased but I
> figure the control system necessary to make this work would be
> prohibitively complicated for a hobby. I'm not saying it couldn't
> be done, but attempting to build such a system could end up being
> a whole hobby in itself.

i fear you might just be right with that..

However i did a quick experiment yesterday.

first i used two screws and passed current through.
(immersed in "old" etchant with much copper)
the iron blackens very fast but one could see copper plating on one screw.


then i used motor brushes (carbon) - you could see copper plating quite
good,
but the brushes seem to dissolve into the etchant.
i thought carbon wouldn't but then maybe only graphite doesn't.

I also noticed that i get clorine gass with any substantial current..
no idea if it can plate withot gas (with low enough voltage).


It seems not so easy to do after all.
But you could solve the whole disposal problem with it.



ST


i add the great link you provided to the links section (if it is not there
already)

--- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan
<stefan_trethan@g...> wrote:

> On Fri, 16 Apr 2004 10:22:49 +1000, Adam Seychell
> <adam_seychell@y...> wrote:
>
> > They use an ion exchange membrane in the regeneration cell. I'm
> > not exactly sure what the membrane is doing in this situation.
> > Obviously its separating ions from anode to cathode.
> > Unfortunately the image showing the electrolytic cell is missing
> > from the web page. I'm sure PVC membranes can be purchased but I
> > figure the control system necessary to make this work would be
> > prohibitively complicated for a hobby. I'm not saying it couldn't
> > be done, but attempting to build such a system could end up being
> > a whole hobby in itself.
>
> i fear you might just be right with that..
>
> However i did a quick experiment yesterday.
>
> first i used two screws and passed current through.
> (immersed in "old" etchant with much copper)
> the iron blackens very fast but one could see copper plating on one

screw.

>
>
> then i used motor brushes (carbon) - you could see copper plating quite
> good,
> but the brushes seem to dissolve into the etchant.
> i thought carbon wouldn't but then maybe only graphite doesn't.
>
> I also noticed that i get clorine gass with any substantial current..
> no idea if it can plate withot gas (with low enough voltage).
>
>
> It seems not so easy to do after all.
> But you could solve the whole disposal problem with it.

The problem with producing chloride gas is the process mechanically
destroys the graphite electrode (anode, positive). Small bubbles
slowly break away at the surface and you end up with graphite power
settling to the bottom of the cell. The cathode (negative) survives ok
because it plates with copper.

The Anode:
Its interesting that chlorine gas is sometimes uses to regenerate CuCl
etchants, and it can also regenerate FeCl3 etchants. Sometimes
electrodes can be attached to a motor and spun so the reactions at the
surface are rapidly mixed in the bulk of the solution. Chlorine gas is
not what we wish to produce and have escape into the air, because it
means we loose it. So by using a spinning anode and careful selection
of current density, it may be possible to get the regeneration
reaction happening without evolving chlorine gas.

The Cathode:
The problem of the copper at the cathode is that its trying to be
etched at the same time being plated out and will make the reaction
less efficient. The article you pointed to had mentioned the PVC
membrane separated the cathode and anode compartments. The cathode
compartment was kept at low copper content of 20g/l instead of the
usual etching strength 150g/l, in order to reduce etching rate of the
copper being plate out. From my experiments with alkaline ammonia
sulfate electrolytic regeneration, I found that the solution near the
surface of cathode must be kept stagnate as possible for the best
results. If the solution was vigorously agitated then the competing
rate of etch would override the rate of plating and therefore no
copper recovery was possible. Effectively the solution just warms up.
The advantage of alkaline ammonia sulfate regeneration is that the
anode reaction does not have problems with gas evolution , and
ordinary 316 stainless still anodes are used. The current density at
the cathode should be high as possible to maximize the ratio of
plating rate to etching rate. The upper limit of current density is
determined by you don't get water electrolysis and evolve hydrogen gas.

At first you might like to setup a test jig with large ratio of anode
to cathode current density in a still solution and both electrodes
still. Set the voltage just before you smell chloride gas or see any
bubbles at the anode. Cheap source of carbon rods is from welding
suppliers. They are coated in thin foil of copper, but that can easily
be etched away.

Adam

--- In Homebrew_PCBs@yahoogroups.com, "adam_seychell"
<adam_seychell@y...> wrote:

> --- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan

> The problem with producing chloride gas is the process mechanically
> destroys the graphite electrode (anode, positive). Small bubbles
> slowly break away at the surface and you end up with graphite power
> settling to the bottom of the cell.

FWIW, I've been using two small titanium rods that I purchased at Home
Depot for around $ 7.00 US. They are impervous to cucl (And for that
matter, any other etchant that I'd be using...) and the copper that
plates out onto them literally slides off in one piece.

Regards

Marvin Dickens

what about clorine gas?
more information please.

ST

On Sat, 17 Apr 2004 03:15:07 -0000, md30022 <md30022@...> wrote:

> --- In Homebrew_PCBs@yahoogroups.com, "adam_seychell"
> <adam_seychell@y...> wrote:
>> --- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan
>
>> The problem with producing chloride gas is the process mechanically
>> destroys the graphite electrode (anode, positive). Small bubbles
>> slowly break away at the surface and you end up with graphite power
>> settling to the bottom of the cell.
>
> FWIW, I've been using two small titanium rods that I purchased at Home
> Depot for around $ 7.00 US. They are impervous to cucl (And for that
> matter, any other etchant that I'd be using...) and the copper that
> plates out onto them literally slides off in one piece.
>
> Regards
>
> Marvin Dickens
>
>
>
>
> Be sure to visit the group home and check for new Bookmarks and files:
> http://groups.yahoo.com/group/Homebrew_PCBs
> Yahoo! Groups Links
>
>
>
>
>

Marvin,

How were these sold? (In other words, I haven't seen "titanium rods"
listed in the hardware section at HD)

Thank you in advance,

Ballendo

--- In Homebrew_PCBs@yahoogroups.com, "md30022" <md30022@y...> wrote:
> FWIW, I've been using two small titanium rods that I purchased at
Home
> Depot for around $ 7.00 US. They are impervous to cucl (And for that
> matter, any other etchant that I'd be using...) and the copper that
> plates out onto them literally slides off in one piece.
>
> Regards
>
> Marvin Dickens

--- ballendo <ballendo@...> wrote:

> Marvin,
>
> How were these sold? (In other words, I haven't seen
> "titanium rods"
> listed in the hardware section at HD)

In the fastner section, I purchased a couple of small
titanium bolts and cut off the portion with the
threads.
I suppose my point is that anything made out of
titanium with do the trick as long as it has a smooth
surface.

Best

Marvin

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--- Stefan Trethan <stefan_trethan@...> wrote:

> what about clorine gas?
> more information please.

Chlorine gas generation is not a problem unless too
much current is used. My rule of thumb is if I see
*any* bubbles, I've got chlorine gas generating. For
sure, low current takes longer to plate out the
copper, but I'm not in a huge hurry (I'm not
manufacturing for money, just as a hobby).

Best

Marvin

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On Sat, 17 Apr 2004 07:37:53 -0700 (PDT), mpdickens <md30022@...>
wrote:

>
> --- Stefan Trethan <stefan_trethan@...> wrote:
>> what about clorine gas?
>> more information please.
>
> Chlorine gas generation is not a problem unless too
> much current is used. My rule of thumb is if I see
> *any* bubbles, I've got chlorine gas generating. For
> sure, low current takes longer to plate out the
> copper, but I'm not in a huge hurry (I'm not
> manufacturing for money, just as a hobby).
>
> Best
>
> Marvin

I feared if i use that low a current the etch may overcome the plating
again.

do you need to add anything to your etchant? replenish chemicals i mean.

I reckon it would not be a problem at all to have two titanium rods in my
tank,
i could get them at ebay..
what have you payed for the screws? i really doubt i can find titanium
screws in any
hardware store here.

One would need to know a surgeon, i have heard you can get titanium screws
easily because
very often they prepare screws for a operation which they then don't use
and they
can't be reused once opened.

ST

--- Stefan Trethan <stefan_trethan@...> wrote:

> I feared if i use that low a current the etch may
> overcome the plating
> again.

The resistance on the rods does rise as copper plates
on to them. However, I've never had the copper content
up to the point that a rise in resistance became a
problem. Like I said, I do small runs and not large
runs that are going to saturate the solution with
copper. Besides, even if I did, an equilibrium would
be reached between copper on the rods and copper
remaining in solution: No more copper would plate out
onto the rods. But, the copper on the robs would not
be dissolved off the rods (Unless there was a decrease
in the current used to pull THAT amount of copper out
of the solution).

Regards

Marvin Dickens

=====
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> The resistance on the rods does rise as copper plates
> on to them. However, I've never had the copper content
> up to the point that a rise in resistance became a
> problem. Like I said, I do small runs and not large
> runs that are going to saturate the solution with
> copper. Besides, even if I did, an equilibrium would
> be reached between copper on the rods and copper
> remaining in solution: No more copper would plate out
> onto the rods. But, the copper on the robs would not
> be dissolved off the rods (Unless there was a decrease
> in the current used to pull THAT amount of copper out
> of the solution).
>
> Regards
>
> Marvin Dickens
>

Oh i didn't fear any problems with the resistance. i do not expect it to
be significant.
I just feared that the etchant will eat away the copper i plated.
just like it is supposed to eat away the copper from the pcb.
I guess you definitely need to take out the electrodes, or at least remove
the
copper if you disconnect the power source for a while.

Have you measured which current/voltage you use? would be very interesting
to know that
and maybe also the estimated electrode surface, and the bath volume, and
electrode distance.

thanks a lot...

ST

Stefan Trethan wrote:

>>The resistance on the rods does rise as copper plates
>>on to them. However, I've never had the copper content
>>up to the point that a rise in resistance became a
>>problem. Like I said, I do small runs and not large
>>runs that are going to saturate the solution with
>>copper. Besides, even if I did, an equilibrium would
>>be reached between copper on the rods and copper
>>remaining in solution: No more copper would plate out
>>onto the rods. But, the copper on the robs would not
>>be dissolved off the rods (Unless there was a decrease
>>in the current used to pull THAT amount of copper out
>>of the solution).
>>
>>Regards
>>
>>Marvin Dickens
>>
>
>
> Oh i didn't fear any problems with the resistance. i do not expect it to
> be significant.
> I just feared that the etchant will eat away the copper i plated.
> just like it is supposed to eat away the copper from the pcb.
> I guess you definitely need to take out the electrodes, or at least remove
> the
> copper if you disconnect the power source for a while.
>
> Have you measured which current/voltage you use? would be very interesting
> to know that
> and maybe also the estimated electrode surface, and the bath volume, and
> electrode distance.
>

Read my earlier post of setting current density *ratios* between the anode
and cathode. You can use large anode surface area to achieve low current
density and avoid chlorine gas evolution. You can use small cathode surface
area to achieve high current density and maximize plating efficiency. But
avoid too high a cathode current density or hydrogen gas will evolve. The
aim is to reduce the copper content to only about 50% to 75% of its
original concentration because copper (2+) is needed to etch. Specific
gravity measurement is the best way to know your copper levels. Sorry, I
don't have any tables on sp.gr verses Cu content.

I would experiment with carbon rods anodes as these are cheaper and easier
to get (see earlier post). The life of graphite rods should be very good
provided chlorine gas is not evolving. You can use stainless steel for the
cathode , but don't leave it in the solution for very long with the current
disconnected or it will corrode. Another option is just plate on another
piece of copper, e.g. a length of copper pluming pipe. I haven't tried
plating copper onto titanium but I suspect it would just fall off as Marvin
said.

Current and voltage for an arbitrary cell depend on too many factors to
have any meaning. Electrode current densities and temperature are the key
parameters you should be seeking.

Adam

> Current and voltage for an arbitrary cell depend on too many factors to
> have any meaning. Electrode current densities and temperature are the key
> parameters you should be seeking.
>
> Adam
>
>

Well, if i can get current densities that would be fine too.
I just want to know if we are talking 10ampere or 100mA here, i have
absolutely no idea.
Also i wonder which supply is needed, i mean is it necesarry to be very
stable current?
(or is a bridge with maybe a filter cap ok?)



I also wondered if it would do any good to connect the board to the anode
at the beginning.
Maybe the electrolytic action would aid in taking off the copper. of
course you can't etch
the entire board this way because there is no way of connecting it but it
takes a long
time until the first patches break free. (certainly more than half the
etch time i think).

Would this work? Can there be significant speedup expected? Would a
electrolytically aided etch
be even or not?


I think i might get titanium sheetmetal for the anode, from which i could
cut stripes
to mount to the pcb holder for connecting to the pcb if it works.
This would allow a big anode area.

I really like the idea of using a copper pipe for the cathode, it is much
cheaper...
For experimenting i will most likely use one.

ST

Question:

Is copper laminate plated with phosphorized copper?

If it is, a cheap source of phosphorized copper for
thru hole plating would be the copper plated out of
cucl...

Regards


Marvin Dickens

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mpdickens wrote:

> Question:
>
> Is copper laminate plated with phosphorized copper?
>
> If it is, a cheap source of phosphorized copper for
> thru hole plating would be the copper plated out of
> cucl...
>
> Regards
>

You are assuming the phosphor releases into solution and co-deposites with
the copper and does so in the same concentration ratio (typically 0.05% P)
they are in the anode material.
Where does the phosphor end up ?

Adam.

Stefan Trethan wrote:

>
> Well, if i can get current densities that would be fine too.
> I just want to know if we are talking 10ampere or 100mA here, i have
> absolutely no idea.

If you don't know the electrode surface area then the answer can
be anywhere from less than 100mA to above 10A.

To take a guess I would start with cathode C.D from 10 to 50
mA/cm^2 and anode C.D from about 2 to 10mA/cm^2.

> Also i wonder which supply is needed, i mean is it necesarry to be very
> stable current?

A constant current source is not essential. Often the voltage can
be set and the cell ohmic resistance is enough to get reasonable
consistent current. When experimenting use a electronic power
supply so you know for sure that your power source is stable. If
you get into full scale then you should worry about power supply
requirments.

>
>
> I also wondered if it would do any good to connect the board to the anode
> at the beginning.
> Maybe the electrolytic action would aid in taking off the copper. of
> course you can't etch
> the entire board this way because there is no way of connecting it but it
> takes a long
> time until the first patches break free. (certainly more than half the
> etch time i think).
>
> Would this work? Can there be significant speedup expected? Would a
> electrolytically aided etch
> be even or not?

Well, one coulomb will plate 0.00034 grams of copper. Typical
double sided "1 oz copper foil" PCB with 50% track area usage and
10 X 15cm size will have total etched copper mass of 4.6 grams.
Total number of coulombs is 4.6 / 0.00034 = 13500

So to electrically etch in 15 minutes will require 15 amps,
and the current density is 15A / (10cm*15cm) = 100mA/cm^2

100mA/cm^2 current density is very high and it might also
decompose water. The free hydrochloric acid content will need to
me very high to keep up with the reaction;
Cu + 2e -> Cu+2

Most plating baths operate around 10 to 30mA/cm^2.

> I think i might get titanium sheetmetal for the anode, from which i could
> cut stripes
> to mount to the pcb holder for connecting to the pcb if it works.
> This would allow a big anode area.

Graphite is often used for anode material in chloride solutions.
I thought titanium anodes forms an oxide layer that gets thicker
with time and eventually the insulation resistance gets so high
the cell becomes too inefficient. Its not unsual for a titanium
anodizing cell to run at 100 Volts !. Titanium anodes are usually
a titanium substrate coated in a precious metal, like platinum.
The advantage being if the titanium substrate is exposed (some
precious metal coating chipped off) then the oxide layer forms
and protects it from further oxidation.

Adam.

>
> A constant current source is not essential. Often the voltage can
> be set and the cell ohmic resistance is enough to get reasonable
> consistent current. When experimenting use a electronic power
> supply so you know for sure that your power source is stable. If
> you get into full scale then you should worry about power supply
> requirments.
>
> ......

Thanks a lot, that gave some numbers.
I will see if i can find carbon electrodes.
I was very afraid using them seeing the carbon brush from the motor
coloring the etchant around it dark, but then i had loads of gas and
the brush may have been dusty with carbon dust.
I think i understand the issues you said may happen with titanium.

ST

I have a 1.2 to 1.4 specific gravity hydrometer floating in the etchant,
do you think i can use this to monitor the process?

Stefan Trethan wrote:

>>A constant current source is not essential. Often the voltage can
>>be set and the cell ohmic resistance is enough to get reasonable
>>consistent current. When experimenting use a electronic power
>>supply so you know for sure that your power source is stable. If
>>you get into full scale then you should worry about power supply
>>requirments.
>>
>>......
>
>
> Thanks a lot, that gave some numbers.
> I will see if i can find carbon electrodes.
> I was very afraid using them seeing the carbon brush from the motor
> coloring the etchant around it dark, but then i had loads of gas and
> the brush may have been dusty with carbon dust.
> I think i understand the issues you said may happen with titanium.
>
> ST
>
> I have a 1.2 to 1.4 specific gravity hydrometer floating in the etchant,
> do you think i can use this to monitor the process?
>
>

I cannot remember the exact numbers but I think 1.2 to 1.3 was
the range. The problem is your test cell may need to be
relatively large >500ml in order to fit hydrometer. Brushes are
made from a copper/graphite composite. The dark color could of
been the copper forming copper(1+), which as you know is dark.
The graphite rods I've used normally just disintegrate into
course powder and settle to the bottom of the container. If no
gas is formed then the rods should in theory last forever.

Adam

>
> I cannot remember the exact numbers but I think 1.2 to 1.3 was
> the range. The problem is your test cell may need to be
> relatively large >500ml in order to fit hydrometer.

i have taylor-made a vertical tank to fit it.
i also have a big test tube where it fits perfectly.

But is can now stay in the tank permanently.

I have choosen to use a "clamp" pcb holder after all,
it is operated with one hand and can hold all pcb thicknesses...

> Brushes are
> made from a copper/graphite composite. The dark color could of
> been the copper forming copper(1+), which as you know is dark.

i think it were the more carbon black brushes, there are some that
are shimmering slightly yellow/red. but you may be right.

> The graphite rods I've used normally just disintegrate into
> course powder and settle to the bottom of the container. If no
> gas is formed then the rods should in theory last forever.

well i guess the carbon power should not disturb the etching process at
all?

have to leave now....

ST

really got some carbon welding rod at the tool shop.
is 8mm dia, 22cm long, copper coated just as you sayd.
cost 1,2eur a piece.

bought 2 and 1 is already soaking in the etchant to get off the copper.

will let you know if i have any results, and of course ask further
questions..

thanks

ST

I have been attempting to find a cheap source of
phosphorized copper (Deoxified copper) for thru hole
plating. I know that phosphorized copper anodes are
typically around 5% phosphor. I have located copper
welding rods that contain 7% phosphor and 93% copper.
Further, these rods do not contain other additives.

Does anybody know if the extra 2% phosphor will make a
difference when plating?

Regards

Marvin Dickens

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mpdickens wrote:

> I have been attempting to find a cheap source of
> phosphorized copper (Deoxified copper) for thru hole
> plating. I know that phosphorized copper anodes are
> typically around 5% phosphor. I have located copper
> welding rods that contain 7% phosphor and 93% copper.
> Further, these rods do not contain other additives.
>
> Does anybody know if the extra 2% phosphor will make a
> difference when plating?

I have no idea, but according to my references, the copper anodes
should contain about 0.05% phosphor.
I think phosphor is only important when using additives, and a
high acid/low copper content bath. i.e the baths used for PCBs.

Adam Seychell wrote:

> mpdickens wrote:
>
>>I have been attempting to find a cheap source of
>>phosphorized copper (Deoxified copper) for thru hole
>>plating. I know that phosphorized copper anodes are
>>typically around 5% phosphor. I have located copper
>>welding rods that contain 7% phosphor and 93% copper.
>>Further, these rods do not contain other additives.
>>
>>Does anybody know if the extra 2% phosphor will make a
>>difference when plating?
>
> I have no idea, but according to my references, the copper anodes
> should contain about 0.05% phosphor.
> I think phosphor is only important when using additives, and a
> high acid/low copper content bath. i.e the baths used for PCBs.

I've heard that phosphorized pcb copper etches easier. I've
found that copper shim stock is much harder to etch in FeCl
than pcb copper, so small additives seem to make a large
difference.