Homebrew PCBs

Hi Guys,

I am working on a new etching tank for Ferric Chloride.  I was using 
two bubble stones for aquariums, one clogged pretty quickly and the 
second one didn't last all that long.

So, I figured I would take a sheet of PCB board and drill a bunch of 
holes in it as a baffle.  The I would run an air hose through it and I 
would have lot's of tiny bubbles coming up.  Nope, I got big bubbles 
out of a couple of the holes.  I started out with .020" diameter 
holes, then tried .035, then .045" and finally .055" holes. Not 
working good at all.

So, I am stumped now and am wondering what you guys are using to get 
better distribution of your air bubbles.

Chris

I have not built something like this myself, but I suspect on a first
pass I would do what you did. Since that did not work I would start
thinking about it like a resistive series/parallel circuit and figure
out what kinds of resistances I would need to get an equal current
appearing out of the parallel branches.

After that I would try adjusting the sizes of the holes or channels
based on what kind of ratios I get from the resistor analogy.

I think I would keep the hole sizes the same, but vary the channel
widths to avoid any issues with capillary effects when going between
liquid and air.


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

>
> Hi Guys,
> 
> I am working on a new etching tank for Ferric Chloride.  I was using 
> two bubble stones for aquariums, one clogged pretty quickly and the 
> second one didn't last all that long.
> 
> So, I figured I would take a sheet of PCB board and drill a bunch of 
> holes in it as a baffle.  The I would run an air hose through it and I 
> would have lot's of tiny bubbles coming up.  Nope, I got big bubbles 
> out of a couple of the holes.  I started out with .020" diameter 
> holes, then tried .035, then .045" and finally .055" holes. Not 
> working good at all.
> 
> So, I am stumped now and am wondering what you guys are using to get 
> better distribution of your air bubbles.
> 
> Chris
>

A flexible bubbler hose works OK for me.
The bubbles are not entirely uniform in density, but at least they are  
small.

It is a black foam hose, with two rows of tiny holes cut in the outside  
with something that must be like a pizza wheel. The hose looks identical  
in make to the black soft foam isolation you get for refrigerant systems,  
i expect is is from such a source only a very small diameter (maybe 1.5cm).
There's a lead wire inside to weigh it down -> remove.


I'd like to have a even more uniform bubbler since i still get streaks on  
the PCB that etch faster, but i haven't found one yet.


BTW what a coincidence - my tank sprung a leak today! Luckily the plastic  
safety container the tank sits in does it's job well. I drained all the  
etchant into bottles and found it leaked in the same place again. The  
etchant seeps through the gap between the edge of a panel and the bottom  
plate which i must not have sealed properly. I had already put silicone  
all the way around the outside of this joint to seal it up when it leaked  
"back then", but i didn't do a terribly good job and such things tend to  
come back and haunt you. So i carefully cut away the old silicone there  
and re-did it properly. Will try tomorrow if it is OK now.

So, if you build a tank, do put silicone right on the edge of each panel  
so this gap is sealed all the way. Check if it is sealed by looking from  
the other side, i did not do that...
The aquarium people manage to hold together the whole tank by gluing only  
at that very edge, i prefer to let one panel protrude so i can put i nice  
bead on the outside of the tank. I glued the first tank outside and  
inside, but it is tricky to get into a narrow tank so i didn't do that  
with this one. It shouldn't be needed when the rest is done properly.

And do make sure the whole thing sits in a larger vessel that is reliable,  
VERY reliable.

ST


On Tue, 11 Jul 2006 17:58:53 +0200, lcdpublishing  
<lcdpublishing@...> wrote:

> Hi Guys,
> I am working on a new etching tank for Ferric Chloride.  I was using
> two bubble stones for aquariums, one clogged pretty quickly and the
> second one didn't last all that long.
> So, I figured I would take a sheet of PCB board and drill a bunch of
> holes in it as a baffle.  The I would run an air hose through it and I
> would have lot's of tiny bubbles coming up.  Nope, I got big bubbles
> out of a couple of the holes.  I started out with .020" diameter
> holes, then tried .035, then .045" and finally .055" holes. Not
> working good at all.
> So, I am stumped now and am wondering what you guys are using to get
> better distribution of your air bubbles.
> Chris

In a message dated 7/11/2006 12:30:58 P.M. Central Daylight Time,  
stefan_trethan@... writes:

There's  a lead wire inside to weigh it down 


What?!?!?   A "household product" sold within the EU  with PLUMBIUM in it?    
   Nah . . . ! !  !           Or?


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

On Tue, 11 Jul 2006 19:53:29 +0200, <JanRwl@...> wrote:

>
> What?!?!?   A "household product" sold within the EU  with PLUMBIUM in  
> it?
>    Nah . . . ! !  !           Or?


maybe it's tin, if i find it again i will check for you.
I bought it before the rohs scare, but i did wonder if the lead wouldn't  
make the fish sick.


ST

In a message dated 7/11/2006 1:20:52 P.M. Central Daylight Time,  
stefan_trethan@... writes:

but i  did wonder if the lead wouldn't  
make the fish  sick.



LOL!
 


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

Hi Chris,

Your holes are way too big. All of your air is going out a few of the 
holes because the air is taking the path of least resistance. You need 
smaller holes and probably fewer of them. You could also increase the 
air flow but that might result in  the etchant 'boiling' out of the tank.

My tank  has about 6 holes and it needs a pretty meaty aquarium pump to 
keep all of them flowing. I don't know the size of the holes but they 
are quite small.

Les

lcdpublishing wrote:

> Hi Guys,
>
> I am working on a new etching tank for Ferric Chloride.  I was using 
> two bubble stones for aquariums, one clogged pretty quickly and the 
> second one didn't last all that long.
>
> So, I figured I would take a sheet of PCB board and drill a bunch of 
> holes in it as a baffle.  The I would run an air hose through it and I 
> would have lot's of tiny bubbles coming up.  Nope, I got big bubbles 
> out of a couple of the holes.  I started out with .020" diameter 
> holes, then tried .035, then .045" and finally .055" holes. Not 
> working good at all.
>
> So, I am stumped now and am wondering what you guys are using to get 
> better distribution of your air bubbles.
>
> Chris
>

I gave up on the fancy etching machine and opted for plastic containers and
rubber gloves.  I don't make a lot of PCBs and my time is not of much value
right now so I can afford to etch manually.

I just put ferric chloride in a small plastic container and float it in a
larger plastic container of hot water.  I like being able to inspect the PCB
during the etching, a gentle 'wipe' with a soft scrub helps move things
along.

I'm just procrastinating on the part to recycle the ferric chloride, most
likely for as long as I have fresh FC in the bottle.

Robert
:D

> -----Message d'origine-----
> De : Homebrew_PCBs@yahoogroups.com 
> [mailto:Homebrew_PCBs@...m] De la part de lcdpublishing
> Envoyé : juillet 11 2006 11:59
> À : Homebrew_PCBs@yahoogroups.com
> Objet : [Homebrew_PCBs] Baffled by a bubbler baffle - what 
> are you guys using?
> 
> 
> Hi Guys,
> 
> I am working on a new etching tank for Ferric Chloride.  I was using 
> two bubble stones for aquariums, one clogged pretty quickly and the 
> second one didn't last all that long.
> 
> So, I figured I would take a sheet of PCB board and drill a bunch of 
> holes in it as a baffle.  The I would run an air hose through 
> it and I 
> would have lot's of tiny bubbles coming up.  Nope, I got big bubbles 
> out of a couple of the holes.  I started out with .020" diameter 
> holes, then tried .035, then .045" and finally .055" holes. Not 
> working good at all.
> 
> So, I am stumped now and am wondering what you guys are using to get 
> better distribution of your air bubbles.
> 
> Chris
> 
> 
> 
> 
> 
> 
> 
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----- Original Message ----- 

From: "Robert Hedan" <robert.hedan@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Tuesday, July 11, 2006 7:58 PM
Subject: RE : [Homebrew_PCBs] Baffled by a bubbler baffle - what are you 
guys using?


I gave up on the fancy etching machine and opted for plastic containers and
rubber gloves.  I don't make a lot of PCBs and my time is not of much value
right now so I can afford to etch manually.

I just put ferric chloride in a small plastic container and float it in a
larger plastic container of hot water.  I like being able to inspect the PCB
during the etching, a gentle 'wipe' with a soft scrub helps move things
along.


I do mine the same way. Results are very good.

Leon

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@...> wrote:
>
> BTW what a coincidence - my tank sprung a leak today! Luckily the 
> plastic  
> safety container the tank sits in does it's job well. I drained all 
> the  
> etchant into bottles and found it leaked in the same place again. 
> The  
> etchant seeps through the gap between the edge of a panel and the 
> bottom  
> plate which i must not have sealed properly. I had already put 
> silicone  
> all the way around the outside of this joint to seal it up when it 
> leaked  
> "back then", but i didn't do a terribly good job and such things 
> tend to  
> come back and haunt you. So i carefully cut away the old silicone 
> there  
> and re-did it properly. Will try tomorrow if it is OK now.
> 
> So, if you build a tank, do put silicone right on the edge of each 
> panel  
> so this gap is sealed all the way. Check if it is sealed by looking 
> from  
> the other side, i did not do that...
> The aquarium people manage to hold together the whole tank by gluing 
> only  
> at that very edge, i prefer to let one panel protrude so i can put i 
> nice  
> bead on the outside of the tank. I glued the first tank outside and  
> inside, but it is tricky to get into a narrow tank so i didn't do 
> that  
> with this one. It shouldn't be needed when the rest is done 
> properly.
> 
> And do make sure the whole thing sits in a larger vessel that is 
> reliable,  
> VERY reliable.
> 
> 

I used Plumber's Goop or Household Goop when I built vertical etching
tanks, rather than silicone. I never had a problem with leaks, but I
used a rather large amount, just to make sure. I like this glue for
pretty much everything, though it's pretty thick, so there are some
jobs for which it's a bit too messy.

I used to keep the etching tank in a 13 qt sweater box (#5 plastic),
and now use the #5 boxes directly. Double-boxing it would probably be
a good idea - if you leave your supplies outside, periodicly check to
make sure the plastics aren't getting brittle.

Never ever store used etchant (or anything, really) in those thin
1-gallon milk/water bottles, either. Heavier #2 containers are the
best thing to keep it in, then store those inside a bigger leak-proof tub.

--- In Homebrew_PCBs@yahoogroups.com, Robert Hedan <robert.hedan@...>
wrote:
>
> I gave up on the fancy etching machine and opted for plastic 
> containers and
> rubber gloves.  I don't make a lot of PCBs and my time is not of 
> much value
> right now so I can afford to etch manually.
> 
> I just put ferric chloride in a small plastic container and float it 
> in a
> larger plastic container of hot water.  I like being able to inspect 
> the PCB
> during the etching, a gentle 'wipe' with a soft scrub helps move 
> things
> along.
> 
> I'm just procrastinating on the part to recycle the ferric chloride, 
> most
> likely for as long as I have fresh FC in the bottle.
> 
> Robert
> :D

Same here. I use a 13 qt sweater box filled half full. A sheet of
acrylic with plastic tabs to 'hold' the pcb or brass sheet face down
in the etchant, with feet so that the top of the acrylic is just
underneath the surface of the etchant.

Make two feet shorter than the other so the board is slightly tilted
and any air bubbles run off.

Recycle: buy 40 volume peroxide, put etchant inside a heat-proof
container (a #2 plastic 5 or 2.5 gallon bucket) inside another
container (another bucket), add very slowly while stirring. 32 oz
peroxide per 2 gallons of etchant, divide quantity as needed. Watch
for foamup and overheating. Add a cup of pool acid every two or three
regenerations. Leave uncovered on a hot day to evaporate and
re-concentrate, not a 100% necessary step.

Strain etchant to make sure all contaminants are out (copper bits,
toner residue, etc) but only after regenerating, as the peroxide.

On Tue, 11 Jul 2006 21:34:15 +0200, fenrir_co <fenrir@...>  
wrote:

>
> I used Plumber's Goop or Household Goop when I built vertical etching
> tanks, rather than silicone. I never had a problem with leaks, but I
> used a rather large amount, just to make sure. I like this glue for
> pretty much everything, though it's pretty thick, so there are some
> jobs for which it's a bit too messy.

Don't sell that here. silicone is pretty good stuff on glass.
I'm still unsure what goop really is, some solvent based adhesive is the  
closest i could come so far.

> I used to keep the etching tank in a 13 qt sweater box (#5 plastic),
> and now use the #5 boxes directly. Double-boxing it would probably be
> a good idea - if you leave your supplies outside, periodicly check to
> make sure the plastics aren't getting brittle.
> Never ever store used etchant (or anything, really) in those thin
> 1-gallon milk/water bottles, either. Heavier #2 containers are the
> best thing to keep it in, then store those inside a bigger leak-proof  
> tub.

I don't know what #2 or #5 plastic is, i'm not familiar with the american  
system (btw. another example of the american obsession to categorize  
things in meaningless numbers, gauges, forms, sizes ... ;-).

I think #2 might be PP (polypropylene), but i really have no idea what #5  
might be. Maybe ABS? Large boxes might likely be made from ABS. Let me  
know if you know the human-brain-compatible name or acronym for #5.

I wouldn't use the thin PET bottles for long term storage, but they'll do  
just fine until tomorrow. PET or PE isn't really that suitable for CuCl  
long-term anyway because the HCl tends to go through it in a very strange  
fashion. If #2 really is PP, it seems OK for FeCl, but i don't expect it  
to be different than PET or PE for CuCl, so i would avoid it.


ST

On Tue, 11 Jul 2006 21:42:02 +0200, fenrir_co <fenrir@...>  
wrote:

>
> Recycle: buy 40 volume peroxide, put etchant inside a heat-proof
> container (a #2 plastic 5 or 2.5 gallon bucket) inside another
> container (another bucket), add very slowly while stirring. 32 oz
> peroxide per 2 gallons of etchant, divide quantity as needed. Watch
> for foamup and overheating. Add a cup of pool acid every two or three
> regenerations. Leave uncovered on a hot day to evaporate and
> re-concentrate, not a 100% necessary step.


I still think you are actually adding CuCl to your FeCl instead of  
regenerating it?
Or where is the iron coming from/the copper removed?

What peroxide concentration are you using for this?

ST

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@...> wrote:
 
> 
> I still think you are actually adding CuCl to your FeCl instead of  
> regenerating it?
> Or where is the iron coming from/the copper removed?
> 
> What peroxide concentration are you using for this?
> 
> ST
>

I've asked several people both in real life and online with better
chemistry skills than I have, and most of them think that it's
probably a little of both. Most generally agree that the excess oxygen
will recombine FeCl2 back to FeCl3, though I'm not sure of the
specifics of how that works. I used to get huge concentric rings of
copper crystals when I regenerated with muriatic acid alone (green,
not sure what kind of crystal they were... anhydrous copper chloride?)
that wouldn't dissolve in the FeCl3, but would instantly melt in
water, which I thought was odd since etchant usually has a pretty
large proportion of water in it. All rinse water goes to hazmat
disposal, which is free for small quantities.

I don't get any kind of solids out of the etchant anymore. I do get
some 'rust' fall-out now, but that could simply be because I
thoroughly regenerated my batch of etchant with anhydrous FeCl3 at one
point, thus doubling the concentration, and there may have been too
much to dissolve completely. It's not enough that the solution would
be mostly CuCl.

The peroxide I use is 12% strength. Each 10 volume = 3% (volume is the
ratio of hydrogen released into the air over a certain duration, or
something odd like that)

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@...> wrote:
>
> On Tue, 11 Jul 2006 21:34:15 +0200, fenrir_co <fenrir@...>  
> wrote:
> 
> >
> > I used Plumber's Goop or Household Goop when I built vertical 
> > etching
> > tanks, rather than silicone. I never had a problem with leaks, but 
> > I
> > used a rather large amount, just to make sure. I like this glue 
> > for
> > pretty much everything, though it's pretty thick, so there are 
> > some
> > jobs for which it's a bit too messy.
> 
> Don't sell that here. silicone is pretty good stuff on glass.
> I'm still unsure what goop really is, some solvent based adhesive is 
> the  
> closest i could come so far.

I believe a similar glue is E6000, yes, it's solvent based. Pretty
strong, I've glued glass to chromed metal with it.

> 
> > I used to keep the etching tank in a 13 qt sweater box (#5 
> > plastic),
> > and now use the #5 boxes directly. Double-boxing it would probably 
> > be
> > a good idea - if you leave your supplies outside, periodicly check 
> > to
> > make sure the plastics aren't getting brittle.
> > Never ever store used etchant (or anything, really) in those thin
> > 1-gallon milk/water bottles, either. Heavier #2 containers are the
> > best thing to keep it in, then store those inside a bigger 
> > leak-proof  
> > tub.
> 
> I don't know what #2 or #5 plastic is, i'm not familiar with the 
> american  
> system (btw. another example of the american obsession to categorize  
> things in meaningless numbers, gauges, forms, sizes ... ;-).
> 
> I think #2 might be PP (polypropylene), but i really have no idea 
> what #5  
> might be. Maybe ABS? Large boxes might likely be made from ABS. Let 
> me  
> know if you know the human-brain-compatible name or acronym for #5.
> 
> I wouldn't use the thin PET bottles for long term storage, but 
> they'll do  
> just fine until tomorrow. PET or PE isn't really that suitable for 
> CuCl  
> long-term anyway because the HCl tends to go through it in a very 
> strange  
> fashion. If #2 really is PP, it seems OK for FeCl, but i don't 
> expect it  
> to be different than PET or PE for CuCl, so i would avoid it.
> 
> 
> ST
>

#2 is High Density Poly-Ethylene, which tends to be highly chemical
resistant (though there are solvents that will eat right through it.
Usually used for food (milk, water jugs) and chemicals (motor oil,
transmission fluid, drain cleaner). It used to be rare to see, but
nowadays I also find paint thinner and acetone in it.

So far none of my experiments with base level radio shack FeCl3 and
various amounts of peroxide, hydrochloric acid, and anhydrous FeCl3
have melted through it over the past three years.

#5 is Polypropylene, not quite as chemical resistant. My etchant
hasn't eaten through any of the sweater boxes I've used, but since
everything is left outside, I replace them once a year or so, because
the plastic will become dry and brittle, and break when picked up with
heavy things in it.

I've had thin #2 milk/water bottles spring leaks on me, causing
ungodly messes, though luckily only with acrylic varnish, and not
etchant. Still a mess, but not a catastrophe.

--- Leon Heller <leon.heller@...> wrote:
> 
> I just put ferric chloride in a small plastic container and float it in a
> larger plastic container of hot water.  I like being able to inspect the PCB
> during the etching, a gentle 'wipe' with a soft scrub helps move things
> along.
> 
> 
> I do mine the same way. Results are very good.

if you gently tap with a (jumbo) cotton swab, or wipe with a very soft brush,
you don't need to float that container anywhere.
ambient temperature is good enough, and you will be amazed with how fast the
copper 'disappears' in front of your eyes...and not the slightest risk of over
etching.
the trick is to 'remove' the used etchant off the surface of the board as fast
as it eats through the copper, really impressive. well that's what the bubbles
are for, but mechanically wiping is even more effective!


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--- fenrir_co <fenrir@...> wrote:
> > I'm just procrastinating on the part to recycle the ferric chloride, 
> > most
> > likely for as long as I have fresh FC in the bottle.

> Recycle: buy 40 volume peroxide, put etchant inside a heat-proof
> container (a #2 plastic 5 or 2.5 gallon bucket) inside another
> container (another bucket), add very slowly while stirring. 32 oz
> peroxide per 2 gallons of etchant, divide quantity as needed. Watch
> for foamup and overheating. Add a cup of pool acid every two or three
> regenerations. Leave uncovered on a hot day to evaporate and
> re-concentrate, not a 100% necessary step.

nope, wrong:
you are NOT recycling ferric chloride! you are MAKING cupric chloride etchant
on the go on top of the dirty exhausted FC!
drop the used FC and use 'pure' CuCl. it's not so dirty and reasonably
transparent!


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>the trick is to 'remove' the used etchant off the surface of the 
>board as fast as it eats through the copper, really impressive. well 
>that's what the bubbles are for, but mechanically wiping is even 
>more effective!

While that's the theory, I'm inclined to believe that the better bubble 
etchers also use the bubbles to move the board away from used etchant. 
In other words the board should be in constant motion and the system 
should be bordering on a state of controlled chaos. The last thing you 
want is a relatively stationary board amidst an orderly stream of 
bubbles even though it seems to meet the theoretical requirements.

--- In Homebrew_PCBs@yahoogroups.com, "Herbert E. Plett" 
<cachureos@...> wrote:
>

--- derekhawkins <eldata@...> wrote:

> >the trick is to 'remove' the used etchant off the surface of the 
> >board as fast as it eats through the copper, really impressive. well 
> >that's what the bubbles are for, but mechanically wiping is even 
> >more effective!
> 
> While that's the theory, I'm inclined to believe that the better bubble 
> etchers also use the bubbles to move the board away from used etchant. 
> In other words the board should be in constant motion ...

no reason to move anything!
when the etchant 'dissolves' some copper, it stays there and avoids further
reaction. the trick is to 'remove' this byproduct off the surface and allow
fresh etchant to reach the copper.
how you best do it is your 'method': bubble it, let density and gravity work,
spray it, wipe it off or whatever pleases you...
my experience (not theory) is to wipe and literally 'see' how the copper
disappears.


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On Fri, 14 Jul 2006 20:17:34 +0200, Herbert E. Plett <cachureos@...>  
wrote:

>
> my experience (not theory) is to wipe and literally 'see' how the copper
> disappears.


Yes, but bubbling does not require user input. I usually have a break  
then...
Wiping will allow you to steer it however so it is totally even.

Spraying is no doubt the most forceful and can be automated, hence it's  
use industrially.

ST

>no reason to move anything!

Don't be silly, motion (agitation) is the key to the success. You 
move your brush up and down the surface to displace used etchant. If 
the surface was moving and your brush was stationary it would have 
the same effect. If both your brush and the surface were moving with 
opposite velocities then the effect would even be greater.

Replace your brush with the bubbles now and you'll see half of my 
point. The other half of my point is that any concentration of 
bubbles in any area of the surface will cause faster etching in that 
area. Moving the surface with respect to the bubbles prevents that 
from happening. And the more chaotic the movement the better.  

Etching in a blender and somehow preventing the board itself from 
being blended/destroyed would probably lead to the fastest etching 
possible. Don't laugh I may just prove this.

--- In Homebrew_PCBs@yahoogroups.com, "Herbert E. Plett" 
<cachureos@...> wrote:
>

--- derekhawkins <eldata@...> wrote:

> >no reason to move anything!
> 
> Don't be silly, motion (agitation) is the key to the success. ...

no, 'motion' is not the key, its the fact you are clearing the copper surface
from the byproduct produced by the chemical reaction. of course I am not
referring to the (microscopic) physical phenomenon of the debris leaving the
surface like ion movement, I mean shaking (or whatever) the board, the fluid,
the container, etc.
 
your blender may be not at all better than other methods if it fails to clear
the copper surface of the non etchant product.

HOW you clean (continuosly) the copper surface and let the etchant get to it is
YOUR METHOD, and there are lots of them. mine is to wipe and have fun watching
the copper disappear. if I had better things to enjoy, I would not be etching
anyway. if I had to mass produce boards I would go with spray and/or some
mechanical wiper.


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>its the fact you are clearing the copper surface
>from the byproduct produced by the chemical reaction

There has to be relative motion between the copper surface, spent 
etchant and fresh etchant for this to be effective. A spray etcher 
makes this patently obvious. An analogy would be cooling/heating by 
convection means. Your brush, the bubbles and some form of 
pump/nozzle arrangement in the case of the spray etcher would be 
analogous to a fan, moving spent etchant away from the surface and 
at the same time moving fresh(er) etchant in its place.

This movement can be accomplished using self contained fluid 
dynamics by rocking the container, agitation or even possibly 
ultrasonics. A blender would be an example of severe agitation.

Your problem here seems to be that you're hell bent on "selling" 
your method of etching which I've certainly tried and still use for 
developing. It's inconvenient and messy especially if you're using 
the brown stuff. An analogy would probably be the manual versus 
automatic transmission in autos. The AT probably has only one thing 
going for it, ease of use, but that's enough to make it the hands 
down choice for most drivers here in the US. Even with soaring gas 
prices, don't expect to see any change in habits anytime soon.

 --- In Homebrew_PCBs@yahoogroups.com, "Herbert E. Plett" 
<cachureos@...> wrote:
>

On 7/15/06, derekhawkins <eldata@...> wrote:

>
> Your problem here seems to be that you're hell bent on "selling"
> your method of etching which I've certainly tried and still use for
> developing.
>


Yes Derek, we have a lot of stongly opinionated folks here. Their way is the
best and only way to do things. And they are trying to convert any reader to
their methods.

It does get a little old, to see the same people posting the same sermon
over and over again. I'm not interested in $1000+ software or photo etching.
Personally I'm happy with the methods and software I am using. I've
researched and made  choices appropriate to my ability and pocketbook.

The purpose of the list should be as a point of reference and information
for someone to make an intelligent decision on the techniques availible. As
well as the successes and problems, and generate ideas to improve them.

There will always be a certain amount of rehashing ideas, as newbies join
the list. But, there is a files section and a search function that seems to
be rarely used. More often than not, it's just another chance for reposting
the same old thing.

Myc


_,_._,___
>


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

--- derekhawkins <eldata@...> wrote:
>... A blender would be an example of severe agitation.

and by no means any warraty that it might be better or work at all... (besides
being dumb)


> Your problem here seems to be that you're hell bent on "selling" 
> your method of etching which I've certainly tried and still use for 
> developing. It's inconvenient and messy especially if you're using 
> the brown stuff. 

just because it's the brown stuff it's so amusing...and not messy at all!
convenience is a subjective matter and requires better definition.
I thought I made clear that there are many methods and anybody can use whatever
he/she finds appropriate. I, for sure, am not 'selling' anything and BTW, I
don't like AT either...

(this thread is becoming personal, I quit)



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