Homebrew PCBs

Hi all,

A few of you may be aware of the... "issues" I've had with LaserStar
film and my Kyocera printer. Basically, the toner ends up forming
blotches as it goes through the fuser. This coupled with the roughly
1.414x (1-stop) light loss through the film makes it damn close to
impossible to get a good transfer.

Unfortunately my laser printer doesn't have a "toner density" option.
It's set automatically when it does the colour calibration :(

Does anyone know of any tricks to darken laser printer toner?

Failing that, does anyone want to make me an offer for the two unopened
packs of LaserStar I have sitting on my bookshelf (and which worked
really nicely with my previous B&W laser printer)?

Thanks,
-- 
Phil.
ygroups@...
http://www.philpem.me.uk/

I used to use inkjet for my transparencies and just got tied of having to replace dried out cartridges.  My printer is an HP LaserJet 4101mfp.  It also cannot be made to make dense transparencies.

So, I developed a method using a black dry erase marker, like are used on white boards.  I use Expo brand and posted some pictures here awhile ago, as I recall.  I have not tried other brands.  Expo was the cheapest at my office supply store.

The procedure is simple.  Just paint over the entire laser transparency on the toner side, let it dry, and wipe of with  a soft tissue like Kleenex.

Procedural Details:

1) Black marker seems to work best and comes off the easiest.  It is harder to get all of the color removed from color markers.
2) Do not scrub with the marker. Just lay on a nice wet layer like when painting with water colors. The transparency image is slightly softened by the solvent in the ink and can be scratched by the felt tip if scrubbed.  If completely dry, you can put on a second layer, which I have not found to be necessary, unless I missed a few spots.
3) Let the marker dry thoroughly (at least 5 min.)
4) The dried marker comes off in little flakes. These can also scratch the surface, if they get caught beneath the tissue and you scrub back and forth.  Just wipe in one direction, then another, etc.
5) Fold the tissue as needed to get a clean surface.  If you need to go back over an area, you can do that, but be careful.  Once the majority of the marker is off of the clear areas, you can be much more aggressive to get traces out of crevices, such as around thermals, if necessary.  I rarely have to do that.
6) I don't think other colors will work.

John 

----- Original Message ----- 
  From: Philip Pemberton 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Sunday, March 18, 2012 3:32 PM
  Subject: [Homebrew_PCBs] Darkening laser printer toner?


    
  Hi all,

  A few of you may be aware of the... "issues" I've had with LaserStar
  film and my Kyocera printer. Basically, the toner ends up forming
  blotches as it goes through the fuser. This coupled with the roughly
  1.414x (1-stop) light loss through the film makes it damn close to
  impossible to get a good transfer.

  Unfortunately my laser printer doesn't have a "toner density" option.
  It's set automatically when it does the colour calibration :(

  Does anyone know of any tricks to darken laser printer toner?

  Failing that, does anyone want to make me an offer for the two unopened
  packs of LaserStar I have sitting on my bookshelf (and which worked
  really nicely with my previous B&W laser printer)?

  Thanks,
  -- 
  Phil.
  ygroups@...
  http://www.philpem.me.uk/


  

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

On Sun, 18 Mar 2012 19:32:57 +0000, you wrote:

>Hi all,
>
>A few of you may be aware of the... "issues" I've had with LaserStar
>film and my Kyocera printer. Basically, the toner ends up forming
>blotches as it goes through the fuser. This coupled with the roughly
>1.414x (1-stop) light loss through the film makes it damn close to
>impossible to get a good transfer.
>
>Unfortunately my laser printer doesn't have a "toner density" option.
>It's set automatically when it does the colour calibration :(
>
>Does anyone know of any tricks to darken laser printer toner?
>
>Failing that, does anyone want to make me an offer for the two unopened
>packs of LaserStar I have sitting on my bookshelf (and which worked
>really nicely with my previous B&W laser printer)?
>
>Thanks,
I've never messed with that brand, but can you tell it that it is printing
on different materials? That may change toner density.

Keith Bowers WB4LSJ- Thomasville, NC

Does anyone know the logistics of the printing protocols when it comes to
density? It sure would be helpful for both transparencies and toner
transfer if we could come up with a hack.

Sent from my iPad

On 2012-03-18, at 2:03 PM, "kabowers@..." <
kabowers@...> wrote:



On Sun, 18 Mar 2012 19:32:57 +0000, you wrote:

>Hi all,
>
>A few of you may be aware of the... "issues" I've had with LaserStar
>film and my Kyocera printer. Basically, the toner ends up forming
>blotches as it goes through the fuser. This coupled with the roughly
>1.414x (1-stop) light loss through the film makes it damn close to
>impossible to get a good transfer.
>
>Unfortunately my laser printer doesn't have a "toner density" option.
>It's set automatically when it does the colour calibration :(
>
>Does anyone know of any tricks to darken laser printer toner?
>
>Failing that, does anyone want to make me an offer for the two unopened
>packs of LaserStar I have sitting on my bookshelf (and which worked
>really nicely with my previous B&W laser printer)?
>
>Thanks,
I've never messed with that brand, but can you tell it that it is printing
on different materials? That may change toner density.

Keith Bowers WB4LSJ- Thomasville, NC

 


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

On 18/03/2012 19:32, Philip Pemberton wrote:
> Hi all,
>
> A few of you may be aware of the... "issues" I've had with LaserStar
> film and my Kyocera printer. Basically, the toner ends up forming
> blotches as it goes through the fuser. This coupled with the roughly
> 1.414x (1-stop) light loss through the film makes it damn close to
> impossible to get a good transfer.
>
> Unfortunately my laser printer doesn't have a "toner density" option.
> It's set automatically when it does the colour calibration :(
>
> Does anyone know of any tricks to darken laser printer toner?

You can buy a solvent which evens out the toner deposit. You'd be better 
off with an inkjet printer, though.

Leon
-- 
Leon Heller
G1HSM

On 18/03/12 21:36, Leon Heller wrote:
> You can buy a solvent which evens out the toner deposit. You'd be better 
> off with an inkjet printer, though.

I know -- my Canon iP4600 does a great job on JetStar Premium. It's just
I've got three packs of LaserStar which I'd like to see working...
otherwise that's £30 and change down the pan.

I'll probably put an order in with Mega over the next couple of days...
something along the lines of:
  * A roll of dry-film photoresist to re-coat these boards
  * a few pre-coated Microtrak boards (though the quality seems to be
hit and miss, the last few I used had a ~10mm wide uncoated patch down
one or two sides.. is Fotoboard2 is any better?)
  * A few of the Seno photoresist developer/stripper packs, and/or maybe
some CPD5 photoresist developer.

And I have a nice big bottle of dark green ferric chloride (isn't that
stuff supposed to be brown?) which is taking 40 odd minutes to etch and
is full of floating crud... time to dump it and mix a fresh batch, I
reckon...

Cheers,
-- 
Phil.
ygroups@philpem.me.uk
http://www.philpem.me.uk/

On 18/03/2012 23:35, Philip Pemberton wrote:
> On 18/03/12 21:36, Leon Heller wrote:
>  > You can buy a solvent which evens out the toner deposit. You'd be better
>  > off with an inkjet printer, though.
>
> I know -- my Canon iP4600 does a great job on JetStar Premium. It's just
> I've got three packs of LaserStar which I'd like to see working...
> otherwise that's \ufffd30 and change down the pan.
>
> I'll probably put an order in with Mega over the next couple of days...
> something along the lines of:
> * A roll of dry-film photoresist to re-coat these boards
> * a few pre-coated Microtrak boards (though the quality seems to be
> hit and miss, the last few I used had a ~10mm wide uncoated patch down
> one or two sides.. is Fotoboard2 is any better?)
> * A few of the Seno photoresist developer/stripper packs, and/or maybe
> some CPD5 photoresist developer.
>
> And I have a nice big bottle of dark green ferric chloride (isn't that
> stuff supposed to be brown?) which is taking 40 odd minutes to etch and
> is full of floating crud... time to dump it and mix a fresh batch, I
> reckon...

Fotoboard 2 works very well for me.

FeCl3 doesn't go off, I've used the same bottle of it for over a year. 
It needs to be used warm, with constant agitation. I can etch a board in 
under 5 minutes.

Leon
-- 
Leon Heller
G1HSM

On 19/03/2012 00:51, Leon Heller wrote:

>  > And I have a nice big bottle of dark green ferric chloride (isn't that
>  > stuff supposed to be brown?) which is taking 40 odd minutes to etch and
>  > is full of floating crud... time to dump it and mix a fresh batch, I
>  > reckon...


If it's dark green, it's probably exhausted.

Leon
-- 
Leon Heller
G1HSM

On 19/03/12 12:18, Leon Heller wrote:
> On 19/03/2012 00:51, Leon Heller wrote:
>
>>   >  And I have a nice big bottle of dark green ferric chloride (isn't that
>>   >  stuff supposed to be brown?) which is taking 40 odd minutes to etch and
>>   >  is full of floating crud... time to dump it and mix a fresh batch, I
>>   >  reckon...
>
>
> If it's dark green, it's probably exhausted.

If it's dark green, it will etch perfectly well using a different chemistry if 
you use bubble agitation, and add a bit of hydrochloric acid from the hardware 
shop every few weeks.

I get full etch in 10-15mins at room temperature like that.

On 19/03/12 08:00, Russell Shaw wrote:
> On 19/03/12 12:18, Leon Heller wrote:
>> If it's dark green, it's probably exhausted.
> 
> If it's dark green, it will etch perfectly well using a different chemistry if 
> you use bubble agitation, and add a bit of hydrochloric acid from the hardware 
> shop every few weeks.
> 
> I get full etch in 10-15mins at room temperature like that.

Well, I've just filtered the etchant through a piece of kitchen roll (my
first choice was coffee filter paper -- I didn't have any, so I figured
kitchen roll would work as an alternate).

I ended up with a green liquid, and brown paper...

So I think it's a fair bet there's some kind of copper salt in the
solution, along with a tiny bit of iron (it's got a yellowish tint to it).

I've thrown in 200ml of brick cleaner (10% HCl, ~£10 for five litres
from B&Q) and set the valve on the air pump to full. Right now I have
foamy green etchant... I'm going to leave it for an hour or so and see
what happens when I throw some FR4 board offcuts in (lord knows I have
plenty of those after last night's complete abortion of a PCB etching
attempt).

This should be interesting...

Thanks,
-- 
Phil.
ygroups@....uk
http://www.philpem.me.uk/

Hi Phil,

This describes the whole process with cupric chloride:  http://members.optusnet.com.au/eseychell/PCB/etching_CuCl/index.html

I have been using it for several years.  Too much acid leads to undercutting, but the amount of acid is difficult for most DIY'ers to access.  Go by specific gravity and color.

John

  ----- Original Message ----- 
  From: Philip Pemberton 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Monday, March 19, 2012 4:39 PM
  Subject: [Homebrew_PCBs] Rejuvenating ferric chloride etchants (was: Darkening laser printer toner?)


    
  On 19/03/12 08:00, Russell Shaw wrote:
  > On 19/03/12 12:18, Leon Heller wrote:
  >> If it's dark green, it's probably exhausted.
  > 
  > If it's dark green, it will etch perfectly well using a different chemistry if 
  > you use bubble agitation, and add a bit of hydrochloric acid from the hardware 
  > shop every few weeks.
  > 
  > I get full etch in 10-15mins at room temperature like that.

  Well, I've just filtered the etchant through a piece of kitchen roll (my
  first choice was coffee filter paper -- I didn't have any, so I figured
  kitchen roll would work as an alternate).

  I ended up with a green liquid, and brown paper...

  So I think it's a fair bet there's some kind of copper salt in the
  solution, along with a tiny bit of iron (it's got a yellowish tint to it).

  I've thrown in 200ml of brick cleaner (10% HCl, ~£10 for five litres
  from B&Q) and set the valve on the air pump to full. Right now I have
  foamy green etchant... I'm going to leave it for an hour or so and see
  what happens when I throw some FR4 board offcuts in (lord knows I have
  plenty of those after last night's complete abortion of a PCB etching
  attempt).

  This should be interesting...

  Thanks,
  -- 
  Phil.
  ygroups@...
  http://www.philpem.me.uk/


  

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

On 19/03/12 21:18, John Anhalt wrote:
> Hi Phil,
> 
> This describes the whole process with cupric chloride:  http://members.optusnet.com.au/eseychell/PCB/etching_CuCl/index.html
> 
> I have been using it for several years.  Too much acid leads to undercutting, but the amount of acid is difficult for most DIY'ers to access.  Go by specific gravity and color.

OK, it looks like what I've ended up with is somewhat close to that --
almost black liquid, but with green foam (and foam it does: I had to
turn the air pump right the way down after it foamed over the side of
the etch tank and onto the concrete floor!)

There's a slight yellow-brown tint to the green, so there's some FeCl3
left in there (or at least some iron-based compound), but I don't think
there's much...

Etch time with air on one-quarter is around 10 minutes, if even that.

Now if only I could get my hands on dry-film photoresist in quantities
less than "two bloomin' great heavy reels" (which seems to be Mega's
preferred sales unit, at a cost of £100-odd plus VAT)...

-- 
Phil.
ygroups@...
http://www.philpem.me.uk/

Phil,
I have used this, a lot less £s than Mega!!

http://www.ebay.co.uk/itm/Photoresist-Dry-Film-A5-x-10-developer-DIY-PCB-Photo-Etched-PE-/250900965034?pt=Vintage_Electronics_R2&hash=item3a6adce6aa

I have used it for over 12 months now, works very well, and if you need to make a "large" board just use two pieces with a slight overlap, works just as well! hope this helps
Rgds
David

--- In Homebrew_PCBs@yahoogroups.com, Philip Pemberton <ygroups@...> wrote:

>
> On 19/03/12 21:18, John Anhalt wrote:
> > Hi Phil,
> > 
> > This describes the whole process with cupric chloride:  http://members.optusnet.com.au/eseychell/PCB/etching_CuCl/index.html
> > 
> > I have been using it for several years.  Too much acid leads to undercutting, but the amount of acid is difficult for most DIY'ers to access.  Go by specific gravity and color.
> 
> OK, it looks like what I've ended up with is somewhat close to that --
> almost black liquid, but with green foam (and foam it does: I had to
> turn the air pump right the way down after it foamed over the side of
> the etch tank and onto the concrete floor!)
> 
> There's a slight yellow-brown tint to the green, so there's some FeCl3
> left in there (or at least some iron-based compound), but I don't think
> there's much...
> 
> Etch time with air on one-quarter is around 10 minutes, if even that.
> 
> Now if only I could get my hands on dry-film photoresist in quantities
> less than "two bloomin' great heavy reels" (which seems to be Mega's
> preferred sales unit, at a cost of £100-odd plus VAT)...
> 
> -- 
> Phil.
> ygroups@...
> http://www.philpem.me.uk/
>

For my aerator, I use an aquarium pump and plastic tubes from the pet store.  I would not recommend the stone variety.

I agree with you on the photoresist.  Occasionally, a seller of small quantities will appear on ebay.  I haven't tried it yet, but have wanted to ever since first reading about it several years ago.  I am afraid the manufacturer for my pre-sensitized boards (Injectorall, available from DigiKey) is about to close shop. 

John

  ----- Original Message ----- 
  From: Philip Pemberton 
  To: Homebrew_PCBs@yahoogroups.com 
  Cc: John Anhalt 
  Sent: Monday, March 19, 2012 5:42 PM
  Subject: Re: [Homebrew_PCBs] Rejuvenating ferric chloride etchants


    
  On 19/03/12 21:18, John Anhalt wrote:
  > Hi Phil,
  > 
  > This describes the whole process with cupric chloride: http://members.optusnet.com.au/eseychell/PCB/etching_CuCl/index.html
  > 
  > I have been using it for several years. Too much acid leads to undercutting, but the amount of acid is difficult for most DIY'ers to access. Go by specific gravity and color.

  OK, it looks like what I've ended up with is somewhat close to that --
  almost black liquid, but with green foam (and foam it does: I had to
  turn the air pump right the way down after it foamed over the side of
  the etch tank and onto the concrete floor!)

  There's a slight yellow-brown tint to the green, so there's some FeCl3
  left in there (or at least some iron-based compound), but I don't think
  there's much...

  Etch time with air on one-quarter is around 10 minutes, if even that.

  Now if only I could get my hands on dry-film photoresist in quantities
  less than "two bloomin' great heavy reels" (which seems to be Mega's
  preferred sales unit, at a cost of £100-odd plus VAT)...

  -- 
  Phil.
  ygroups@...
  http://www.philpem.me.uk/


  

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

That is negative acting film.  I meant the positive acting stuff.  I believe the positive acting resists have simpler developer systems.

John

  ----- Original Message ----- 
  From: David 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Monday, March 19, 2012 6:06 PM
  Subject: [Homebrew_PCBs] Re: Rejuvenating ferric chloride etchants


    
  Phil,
  I have used this, a lot less £s than Mega!!

  http://www.ebay.co.uk/itm/Photoresist-Dry-Film-A5-x-10-developer-DIY-PCB-Photo-Etched-PE-/250900965034?pt=Vintage_Electronics_R2&hash=item3a6adce6aa

  I have used it for over 12 months now, works very well, and if you need to make a "large" board just use two pieces with a slight overlap, works just as well! hope this helps
  Rgds
  David

  --- In Homebrew_PCBs@yahoogroups.com, Philip Pemberton <ygroups@...> wrote:
  >
  > On 19/03/12 21:18, John Anhalt wrote:
  > > Hi Phil,
  > > 
  > > This describes the whole process with cupric chloride: http://members.optusnet.com.au/eseychell/PCB/etching_CuCl/index.html
  > > 
  > > I have been using it for several years. Too much acid leads to undercutting, but the amount of acid is difficult for most DIY'ers to access. Go by specific gravity and color.
  > 
  > OK, it looks like what I've ended up with is somewhat close to that --
  > almost black liquid, but with green foam (and foam it does: I had to
  > turn the air pump right the way down after it foamed over the side of
  > the etch tank and onto the concrete floor!)
  > 
  > There's a slight yellow-brown tint to the green, so there's some FeCl3
  > left in there (or at least some iron-based compound), but I don't think
  > there's much...
  > 
  > Etch time with air on one-quarter is around 10 minutes, if even that.
  > 
  > Now if only I could get my hands on dry-film photoresist in quantities
  > less than "two bloomin' great heavy reels" (which seems to be Mega's
  > preferred sales unit, at a cost of £100-odd plus VAT)...
  > 
  > -- 
  > Phil.
  > ygroups@...
  > http://www.philpem.me.uk/
  >



  

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

On 19/03/12 22:14, John Anhalt wrote:
> That is negative acting film.  I meant the positive acting stuff.  I believe the positive acting resists have simpler developer systems.

To be honest, I don't mind :)
(the Mega stuff is negative-acting too)

I've tried spray-on photoresists -- the "new formula" Electrolube PRP is
a complete joke, and damn close to impossible to use reliably. I've got
a Seno SN100 roll-on photoresist dispenser on my Mega order, so I'll see
if that's up to much (a message posted here by Leon Heller back in 2004
suggests that it's far better than Electrolube's laughable attempt at a
photoresist coating).

I'm willing to wager that applying it fairly evenly then putting it in
my homebrew spin-coater (read: a PC fan mated to a programmable speed
controller) will produce a nice, even photoresist layer.

What I'd really like is a can of Kontakt-Chemie POSITIV-20, which can
apparently be used as a paint for front panels. You spray it on, expose
to UV as normal, then develop and dry. Heat it to a hundred degrees or
so, and leave it until the resist changes colour (it'll go from blue to
dark brown). Overcoat with clear lacquer.

Comments on Rapid's website seem to suggest this works with SN100 (aka
POSITIV-100) too... I might have to try it, though I doubt a brown
component print on green soldermask would look very nice.

Thanks,
-- 
Phil.
ygroups@...
http://www.philpem.me.uk/

There's also this option for photo laminate:
http://tech.groups.yahoo.com/group/Homebrew_PCBs/message/29135

Sent from my iPad

On 2012-03-19, at 4:54 PM, Philip Pemberton <ygroups@...> wrote:



On 19/03/12 22:14, John Anhalt wrote:
> That is negative acting film. I meant the positive acting stuff. I
believe the positive acting resists have simpler developer systems.

To be honest, I don't mind :)
(the Mega stuff is negative-acting too)

I've tried spray-on photoresists -- the "new formula" Electrolube PRP is
a complete joke, and damn close to impossible to use reliably. I've got
a Seno SN100 roll-on photoresist dispenser on my Mega order, so I'll see
if that's up to much (a message posted here by Leon Heller back in 2004
suggests that it's far better than Electrolube's laughable attempt at a
photoresist coating).

I'm willing to wager that applying it fairly evenly then putting it in
my homebrew spin-coater (read: a PC fan mated to a programmable speed
controller) will produce a nice, even photoresist layer.

What I'd really like is a can of Kontakt-Chemie POSITIV-20, which can
apparently be used as a paint for front panels. You spray it on, expose
to UV as normal, then develop and dry. Heat it to a hundred degrees or
so, and leave it until the resist changes colour (it'll go from blue to
dark brown). Overcoat with clear lacquer.

Comments on Rapid's website seem to suggest this works with SN100 (aka
POSITIV-100) too... I might have to try it, though I doubt a brown
component print on green soldermask would look very nice.

Thanks,
-- 
Phil.
ygroups@...
http://www.philpem.me.uk/
 


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

On 19/03/12 22:10, John Anhalt wrote:
> For my aerator, I use an aquarium pump and plastic tubes from the pet
> store.  I would not recommend the stone variety.

Funny you should say that.... you just described the aeration setup in
my etch tank :)

I've got one of those foam bubbler hoses glued to the bottom of the tank
with five-minute epoxy, then a hose running up one side to an aquarium
air pump.

I've also got the option of using a VisiTherm heater to warm the
etchant, but I need to fix the holder -- the rubber pads have started to
degrade and no longer stick to the plastic tank wall. In any case, it's
only a 50W heater and takes ages to bring the tank up to a reasonable
temperature.

> I agree with you on the photoresist.  Occasionally, a seller of small
> quantities will appear on ebay.  I haven't tried it yet, but have
> wanted to ever since first reading about it several years ago.  I am
> afraid the manufacturer for my pre-sensitized boards (Injectorall,
> available from DigiKey) is about to close shop.

Thankfully I don't think Mega are going that way -- they seem to have
been around for many years, and actually make two different precoated
boards --
  - Fotoboard2 -- a roller-coated positive-acting board (Leon seems to
like this one, I haven't tried it.. yet). Rapid sell this quite cheaply.
  - Microtrak -- dip-coated, positive acting. Apparently produced by
Instagraphic Products, then later by Mega themselves. Allegedly better
for fine-pitch work, bugger all price difference vs. Fotoboard (IIRC
Fotoboard is about 5p cheaper). I've had problems with one or two edges
of this stuff being uncoated, up to 1/3rd of an inch from the edge...

Well, I've got 10x Fotoboard2 blanks on order.. who knows, maybe they'll
work better than Microtrak?

Thanks,
-- 
Phil.
ygroups@...
http://www.philpem.me.uk/

I spoke with the owner of Injectorall a couple of years ago.  It is dip coated and gives very nice resolution.  That is why I am reluctant to give it up.  I'm in the USA and have not heard of the brands you mention.  

John

  ----- Original Message ----- 
  From: Philip Pemberton 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Monday, March 19, 2012 8:03 PM
  Subject: Re: [Homebrew_PCBs] Rejuvenating ferric chloride etchants


    
  On 19/03/12 22:10, John Anhalt wrote:
  > For my aerator, I use an aquarium pump and plastic tubes from the pet
  > store. I would not recommend the stone variety.

  Funny you should say that.... you just described the aeration setup in
  my etch tank :)

  I've got one of those foam bubbler hoses glued to the bottom of the tank
  with five-minute epoxy, then a hose running up one side to an aquarium
  air pump.

  I've also got the option of using a VisiTherm heater to warm the
  etchant, but I need to fix the holder -- the rubber pads have started to
  degrade and no longer stick to the plastic tank wall. In any case, it's
  only a 50W heater and takes ages to bring the tank up to a reasonable
  temperature.

  > I agree with you on the photoresist. Occasionally, a seller of small
  > quantities will appear on ebay. I haven't tried it yet, but have
  > wanted to ever since first reading about it several years ago. I am
  > afraid the manufacturer for my pre-sensitized boards (Injectorall,
  > available from DigiKey) is about to close shop.

  Thankfully I don't think Mega are going that way -- they seem to have
  been around for many years, and actually make two different precoated
  boards --
  - Fotoboard2 -- a roller-coated positive-acting board (Leon seems to
  like this one, I haven't tried it.. yet). Rapid sell this quite cheaply.
  - Microtrak -- dip-coated, positive acting. Apparently produced by
  Instagraphic Products, then later by Mega themselves. Allegedly better
  for fine-pitch work, bugger all price difference vs. Fotoboard (IIRC
  Fotoboard is about 5p cheaper). I've had problems with one or two edges
  of this stuff being uncoated, up to 1/3rd of an inch from the edge...

  Well, I've got 10x Fotoboard2 blanks on order.. who knows, maybe they'll
  work better than Microtrak?

  Thanks,
  -- 
  Phil.
  ygroups@...
  http://www.philpem.me.uk/


  

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

On 20/03/12 08:42, Philip Pemberton wrote:
> On 19/03/12 21:18, John Anhalt wrote:
>> Hi Phil,
>>
>> This describes the whole process with cupric chloride:
>> http://members.optusnet.com.au/eseychell/PCB/etching_CuCl/index.html
>>
>> I have been using it for several years.  Too much acid leads to
>> undercutting, but the amount of acid is difficult for most DIY'ers to
>> access.  Go by specific gravity and color.
>
> OK, it looks like what I've ended up with is somewhat close to that -- almost
> black liquid, but with green foam (and foam it does: I had to turn the air
> pump right the way down after it foamed over the side of the etch tank and
> onto the concrete floor!)

Foaming too much sounds like you need to dilute with more water (like 50-100%).
Add some HCl for faster etching too.

> There's a slight yellow-brown tint to the green, so there's some FeCl3 left
> in there (or at least some iron-based compound), but I don't think there's
> much...
>
> Etch time with air on one-quarter is around 10 minutes, if even that.
>
> Now if only I could get my hands on dry-film photoresist in quantities less
> than "two bloomin' great heavy reels" (which seems to be Mega's preferred
> sales unit, at a cost of \ufffd100-odd plus VAT)...

On 20/03/12 07:39, Philip Pemberton wrote:
> On 19/03/12 08:00, Russell Shaw wrote:
>> On 19/03/12 12:18, Leon Heller wrote:
>>> If it's dark green, it's probably exhausted.
>>
>> If it's dark green, it will etch perfectly well using a different chemistry if
>> you use bubble agitation, and add a bit of hydrochloric acid from the hardware
>> shop every few weeks.
>>
>> I get full etch in 10-15mins at room temperature like that.
>
> Well, I've just filtered the etchant through a piece of kitchen roll (my
> first choice was coffee filter paper -- I didn't have any, so I figured
> kitchen roll would work as an alternate).
>
> I ended up with a green liquid, and brown paper...
>
> So I think it's a fair bet there's some kind of copper salt in the
> solution, along with a tiny bit of iron (it's got a yellowish tint to it).
>
> I've thrown in 200ml of brick cleaner (10% HCl, ~\ufffd10 for five litres
> from B&Q) and set the valve on the air pump to full. Right now I have
> foamy green etchant... I'm going to leave it for an hour or so and see
> what happens when I throw some FR4 board offcuts in (lord knows I have
> plenty of those after last night's complete abortion of a PCB etching
> attempt).
>
> This should be interesting...

I would have added the HCl, but also left the solids in there to dissolve. You 
may have removed the active ingredients;)

--- In Homebrew_PCBs@yahoogroups.com, Philip Pemberton <ygroups@...> wrote:
>
> On 19/03/12 22:10, John Anhalt wrote:
>
> I've got one of those foam bubbler hoses glued to the bottom of the
> tank with five-minute epoxy, then a hose running up one side to an
> aquarium air pump.

I'm interested in that "foam bubbler hose" you mention, but I've never seen it.  Do you have a link to a source for the item or at least a photo of it so I can know what to look for or ask for at the pet supply store?

Thanks.

Here's a guy whose rejuvenation chemistry has allowed him to use the same ferric chloride etchant for four years (watch that chlorine gas, though):

http://www.qsl.net/iz7ath/web/02_brew/14_howto/02_clor/index.htm

BTW, has anyone ever tried this (add citric acid to etchant)?:

FERRIC CHLORIDE AND THE EDINBURGH ETCH

http://www.lawrence.co.uk/acatalog/etch.pdf

I use Edinburgh etch in my heated bubble tank, <http://www.megauk.com/pcb_processing_tanks.php> they doa hobby version too, < http://www.megauk.com/hobby_equipment.php> 

The etch seems tospeed up the more you use it and the older it gets.
I was given the tank with its faulty control system (it had been etched as well). I built a newone in an IP67 box with electronic temp control.

Malcolm
 
I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.


________________________________

 From: sheldon_mp_cooper <bigbazinga@...>
To: Homebrew_PCBs@yahoogroups.com 
Sent: Tuesday, March 20, 2012 7:02 PM
Subject: [Homebrew_PCBs] Re: Rejuvenating ferric chloride etchants (was: Darkening laser printer toner?)
 

  
Here's a guy whose rejuvenation chemistry has allowed him to use the same ferric chloride etchant for four years (watch that chlorine gas, though):

http://www.qsl.net/iz7ath/web/02_brew/14_howto/02_clor/index.htm

BTW, has anyone ever tried this (add citric acid to etchant)?:

FERRIC CHLORIDE AND THE EDINBURGH ETCH

http://www.lawrence.co.uk/acatalog/etch.pdf


 

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

On 20/03/2012 19:51, sheldon_mp_cooper wrote:
>
> --- In Homebrew_PCBs@yahoogroups.com 
> <mailto:Homebrew_PCBs%40yahoogroups.com>, Philip Pemberton 
> <ygroups@...> wrote:
> >
> > On 19/03/12 22:10, John Anhalt wrote:
> >
> > I've got one of those foam bubbler hoses glued to the bottom of the
> > tank with five-minute epoxy, then a hose running up one side to an
> > aquarium air pump.
>
> I'm interested in that "foam bubbler hose" you mention, but I've never 
> seen it. Do you have a link to a source for the item or at least a 
> photo of it so I can know what to look for or ask for at the pet 
> supply store?
>
> Thanks.
>
> __._
>
>
> 
Aren't those hoses also used for trickle irrigation in gardens? They 
look like grey, thick walled, foamy garden hoses.
I've had a lot of aquariums but have never come across the type of 
aeration system you describe.
Interesting application though.

Bert


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

There is a bit of a misquote there.  I do not glue my bubblers to the tank.

I use "Bubble Wall," which is made by Penn-Plax, Hauppauge, NY, USA (www.pennplax.com).  They are a lot smaller than a soaker hose.

John

  ----- Original Message ----- 
  From: Bert Van Kets 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Wednesday, March 21, 2012 3:37 AM
  Subject: Re: [Homebrew_PCBs] Re: Rejuvenating ferric chloride etchants


    
  On 20/03/2012 19:51, sheldon_mp_cooper wrote:
  >
  > --- In Homebrew_PCBs@yahoogroups.com 
  > <mailto:Homebrew_PCBs%40yahoogroups.com>, Philip Pemberton 
  > <ygroups@...> wrote:
  > >
  > > On 19/03/12 22:10, John Anhalt wrote:
  > >
  > > I've got one of those foam bubbler hoses glued to the bottom of the
  > > tank with five-minute epoxy, then a hose running up one side to an
  > > aquarium air pump.
  >
  > I'm interested in that "foam bubbler hose" you mention, but I've never 
  > seen it. Do you have a link to a source for the item or at least a 
  > photo of it so I can know what to look for or ask for at the pet 
  > supply store?
  >
  > Thanks.
  >
  > __._
  >
  >
  > 
  Aren't those hoses also used for trickle irrigation in gardens? They 
  look like grey, thick walled, foamy garden hoses.
  I've had a lot of aquariums but have never come across the type of 
  aeration system you describe.
  Interesting application though.

  Bert

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



  

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

On Wed, 21 Mar 2012 05:47:59 -0400, you wrote:

>There is a bit of a misquote there.  I do not glue my bubblers to the tank.
>
>I use "Bubble Wall," which is made by Penn-Plax, Hauppauge, NY, USA (www.pennplax.com).  They are a lot smaller than a soaker hose.
>
>John
>  ----- Original Message ----- 
>  From: Bert Van Kets 
>  To: Homebrew_PCBs@yahoogroups.com 
>  Sent: Wednesday, March 21, 2012 3:37 AM
>  Subject: Re: [Homebrew_PCBs] Re: Rejuvenating ferric chloride etchants
>
>
>    
>  On 20/03/2012 19:51, sheldon_mp_cooper wrote:
>  >
>  > --- In Homebrew_PCBs@yahoogroups.com 
>  > <mailto:Homebrew_PCBs%40yahoogroups.com>, Philip Pemberton 
>  >
Years ago I used aquarium aerators in FeCl with good results.  I suspended
the board over the liquid such that the bubbles/foam washed over the
face of the board. Etched really quickly with nice sharp edges.

When I started with CuCl I purchased an aerator from WalMart
and the CuCl immediately turned it into a pile of sand 8=(.

Keith Bowers WB4LSJ- Thomasville, NC

On 21/03/2012 14:03, kabowers@... wrote:
>
> On Wed, 21 Mar 2012 05:47:59 -0400, you wrote:
>
> >There is a bit of a misquote there. I do not glue my bubblers to the 
> tank.
> >
> >I use "Bubble Wall," which is made by Penn-Plax, Hauppauge, NY, USA 
> (www.pennplax.com). They are a lot smaller than a soaker hose.
> >
> >John
> > ----- Original Message -----
> > From: Bert Van Kets
> > To: Homebrew_PCBs@yahoogroups.com 
> <mailto:Homebrew_PCBs%40yahoogroups.com>
> > Sent: Wednesday, March 21, 2012 3:37 AM
> > Subject: Re: [Homebrew_PCBs] Re: Rejuvenating ferric chloride etchants
> >
> >
> >
> > On 20/03/2012 19:51, sheldon_mp_cooper wrote:
> > >
> > > --- In Homebrew_PCBs@yahoogroups.com 
> <mailto:Homebrew_PCBs%40yahoogroups.com>
> > > <mailto:Homebrew_PCBs%40yahoogroups.com>, Philip Pemberton
> > >
> Years ago I used aquarium aerators in FeCl with good results. I suspended
> the board over the liquid such that the bubbles/foam washed over the
> face of the board. Etched really quickly with nice sharp edges.
>
> When I started with CuCl I purchased an aerator from WalMart
> and the CuCl immediately turned it into a pile of sand 8=(.
>
> Keith Bowers WB4LSJ- Thomasville, NC
>
> 
Some glues won't withstand the acids.
You can use any porous material though. I have used bits of balsa wood 
as an aerator. Other woods are bound to work well too as long as they 
are very light and have an open structure. Worst case you can use a bit 
of sponge and a rubber band.

Bert


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

On Wed, 21 Mar 2012 05:47:59 -0400, you wrote:

>There is a bit of a misquote there.  I do not glue my bubblers to the tank.
>
>I use "Bubble Wall," which is made by Penn-Plax, Hauppauge, NY, USA (www.pennplax.com).  They are a lot smaller than a soaker hose.

I've used a bubble stone, only to have the ferric chloride eat it. Not
sure that the CuCl etchant wouldn't do the same.  What etchant are you
using and does it have this problem?

Harvey

>
>John

I wonder why more people aren't using it then.  It is also mentioned here:

"SUPER CHARGING Ferric Chloride"
A new additive to help this etchant be more effective!

http://www.pcbfx.com/main_site/pages/tech_support/no_etching_tank.html

and at the link they refer to, I came up with the following info for making it:

http://www.polymetaal.nl/beguin/mape/edinburgh_etch.htm

Edinburgh etch mix ratio for copper etching:

1 liter saturated ferric chloride solution
200ml hot tap water
67 grams citric acid powder

or

32 fluid ounces saturated ferric chloride solution
6.75 fluid ounces hot water
2.36 ounces citric acid powder

Citric acid powder is typically available in 3 oz. bottles at beer brewing/wine making supply stores in the US.

"Gradually add the citric acid powder to the hot water while stirring continually. Once this has fully dissolved, gradually pour this into the ferric solution and keep stirring until you have produced a uniform liquid.

\ufeff"Good results are ensured at 18 to 20°C, but higher temperatures of up to 30°C can further improve biting times as well as the overall responsiveness of the mordant (aka etchant). This mordant is exceptionally long lasting; a tank filling used daily at the EPW, occasionally topped up to compensate for evaporation loss, has been known to remain active for up to one year without a significant drop in its biting properties.  When eventually the mordant acquires a deep olive colour it becomes less active and is then ready for replacement and disposal.


--- In Homebrew_PCBs@yahoogroups.com, Malcolm Parker-Lisberg <mparkerlisberg@...> wrote:

>
> I use Edinburgh etch in my heated bubble tank, <http://www.megauk.com/pcb_processing_tanks.php> they doa hobby version too, < http://www.megauk.com/hobby_equipment.php> 
> 
> The etch seems tospeed up the more you use it and the older it gets.
> I was given the tank with its faulty control system (it had been etched as well). I built a newone in an IP67 box with electronic temp control.
> 
> Malcolm
> Â 
> I don't suffer from insanity I enjoy it!
> Mene, mene, tekel, upharsin
> The writing is on the wall.
> 
> 
> ________________________________
>  From: sheldon_mp_cooper <bigbazinga@...>
> To: Homebrew_PCBs@yahoogroups.com 
> Sent: Tuesday, March 20, 2012 7:02 PM
> Subject: [Homebrew_PCBs] Re: Rejuvenating ferric chloride etchants (was: Darkening laser printer toner?)
>  
> 
> Â  
> Here's a guy whose rejuvenation chemistry has allowed him to use the same ferric chloride etchant for four years (watch that chlorine gas, though):
> 
> http://www.qsl.net/iz7ath/web/02_brew/14_howto/02_clor/index.htm
> 
> BTW, has anyone ever tried this (add citric acid to etchant)?:
> 
> FERRIC CHLORIDE AND THE EDINBURGH ETCH
> 
> http://www.lawrence.co.uk/acatalog/etch.pdf
> 
> 
>  
> 
> [Non-text portions of this message have been removed]
>

On 22/03/12 11:11, sheldon_mp_cooper wrote:
> I wonder why more people aren't using it then.  It is also mentioned here:
>
> "SUPER CHARGING Ferric Chloride" A new additive to help this etchant be more
> effective!
>
> http://www.pcbfx.com/main_site/pages/tech_support/no_etching_tank.html
>
> and at the link they refer to, I came up with the following info for making
> it:
>
> http://www.polymetaal.nl/beguin/mape/edinburgh_etch.htm
>
> Edinburgh etch mix ratio for copper etching:
>
> 1 liter saturated ferric chloride solution 200ml hot tap water 67 grams
> citric acid powder
>
> or
>
> 32 fluid ounces saturated ferric chloride solution 6.75 fluid ounces hot
> water 2.36 ounces citric acid powder
>
> Citric acid powder is typically available in 3 oz. bottles at beer
> brewing/wine making supply stores in the US.

Citric acid powder is available from the local supermarkets in Australia here.

> "Gradually add the citric acid powder to the hot water while stirring
> continually. Once this has fully dissolved, gradually pour this into the
> ferric solution and keep stirring until you have produced a uniform liquid.
>
> \ufeff"Good results are ensured at 18 to 20\ufffdC, but higher temperatures of
> up to 30\ufffdC can further improve biting times as well as the overall
> responsiveness of the mordant (aka etchant). This mordant is exceptionally
> long lasting; a tank filling used daily at the EPW, occasionally topped up to
> compensate for evaporation loss, has been known to remain active for up to
> one year without a significant drop in its biting properties.  When
> eventually the mordant acquires a deep olive colour it becomes less active
> and is then ready for replacement and disposal.

The deep olive colour is when to add HCl and use as a long-term etchant.

--- In Homebrew_PCBs@yahoogroups.com, Russell Shaw <rjshaw@...> wrote:
>
> The deep olive colour is when to add HCl and use as a long-term 
> etchant.

But, at that point, highly dangerous chlorine gas WILL be generated from the reaction, as was warned about in the other link I referred to where the gent said he'd used the same etchant for four years.

A number of years ago, I had done some rough calculations and a 
bit of empirical testing (which turned out mostly unsatisfactorily), 
involving electrolytically regenerating spent Ferric Chloride 
solution.  My approach involved electrolytically depositing the 
Copper out of the solution, and replacing it with Iron.  The
electrolytic deposition of the Copper did work (I ended up with
some beautiful looking "Copper trees".), and the Iron anode
did dissolve.  There was little (if any) Chlorine gas evolved.
But, I'm not real sure that the Iron that was dissolved formed
Ferric Chloride, or some other allotrope (e.g., Ferrous Chloride, 
etc.).  However, it may be worthy of further study.

Note that one of the problems with etching Copper with Ferric 
Chloride solution is that the result is a Copper Chloride, as well
as a Ferric Hydroxide (that brown, muddy looking stuff).  The
Ferric Hydroxide has to be removed from the active area of etching,
or it'll clog up the etching process.

http://en.wikipedia.org/wiki/Ferric_hydroxide

Theoretically, the Ferric Hydroxide could be filtered out of
spent solution.  Maybe.  

As for suspending boards, based on personal experience, Mylon is 
no good, since the Ferric Chloride will attack it.  For that matter,
Chlorine attacks a LOT of things.  PVC, or PVDC, should be fairly
good, since those have quite a few Chlorine atoms on the chain 
already.

Dave

On 22/03/2012 16:30, Dave wrote:
> A number of years ago, I had done some rough calculations and a
> bit of empirical testing (which turned out mostly unsatisfactorily),
> involving electrolytically regenerating spent Ferric Chloride
> solution. My approach involved electrolytically depositing the
> Copper out of the solution, and replacing it with Iron. The
> electrolytic deposition of the Copper did work (I ended up with
> some beautiful looking "Copper trees".), and the Iron anode
> did dissolve. There was little (if any) Chlorine gas evolved.
> But, I'm not real sure that the Iron that was dissolved formed
> Ferric Chloride, or some other allotrope (e.g., Ferrous Chloride,
> etc.). However, it may be worthy of further study.
>
> Note that one of the problems with etching Copper with Ferric
> Chloride solution is that the result is a Copper Chloride, as well
> as a Ferric Hydroxide (that brown, muddy looking stuff). The
> Ferric Hydroxide has to be removed from the active area of etching,
> or it'll clog up the etching process.

Cupric chloride is a good etchant, so you didn't need to remove the 
copper! You just needed to add some HCl and bubble air through it, or 
use some H2O2 to oxidise the mixture.

Leon
-- 
Leon Heller
G1HSM

On 23/03/12 02:07, sheldon_mp_cooper wrote:
> --- In Homebrew_PCBs@yahoogroups.com, Russell Shaw<rjshaw@...>  wrote:
>>

>> The deep olive colour is when to add HCl and use as a long-term etchant.
>
> But, at that point, highly dangerous chlorine gas WILL be generated from the
> reaction, as was warned about in the other link I referred to where the gent
> said he'd used the same etchant for four years.

Adding a cup of HCl to a litre of spent or unspent ferric chloride will cause 
absolutely no outgassing whatsoever.

--- In Homebrew_PCBs@yahoogroups.com, Russell Shaw <rjshaw@...> wrote:
>
> On 23/03/12 02:07, sheldon_mp_cooper wrote:
> > --- In Homebrew_PCBs@yahoogroups.com, Russell Shaw<rjshaw@>  wrote:
> >>
> 
> >> The deep olive colour is when to add HCl and use as a long-term etchant.
> >
> > But, at that point, highly dangerous chlorine gas WILL be generated from the
> > reaction, as was warned about in the other link I referred to where the gent
> > said he'd used the same etchant for four years.
> 
> Adding a cup of HCl to a litre of spent or unspent ferric chloride will cause absolutely no outgassing whatsoever.

Well, I guess you must be speaking from experience and I haven't done this myself, but this gent who has says it will:

http://www.qsl.net/iz7ath/web/02_brew/14_howto/02_clor/index.htm

Excerpt:

"It's necessary to regenerate it;

1)At first it's necessary to raise the acidity, adding hydrochloridic acid HCl (you'll find at shop as muriatic acid, mixed with water.....ask mum); make this work in a open place (DANGEROUS GAS) addig HCl until the muddiness in the tank disappears (or you can also use a litmus paper)."

On 24/03/12 01:46, sheldon_mp_cooper wrote:
> --- In Homebrew_PCBs@yahoogroups.com, Russell Shaw<rjshaw@...>  wrote:
>>
>> On 23/03/12 02:07, sheldon_mp_cooper wrote:
>>> --- In Homebrew_PCBs@yahoogroups.com, Russell Shaw<rjshaw@>   wrote:
>>>>
>>
>>>> The deep olive colour is when to add HCl and use as a long-term
>>>> etchant.
>>>
>>> But, at that point, highly dangerous chlorine gas WILL be generated from
>>> the reaction, as was warned about in the other link I referred to where
>>> the gent said he'd used the same etchant for four years.
>>
>> Adding a cup of HCl to a litre of spent or unspent ferric chloride will
>> cause absolutely no outgassing whatsoever.
>
> Well, I guess you must be speaking from experience and I haven't done this
> myself, but this gent who has says it will:
>
> http://www.qsl.net/iz7ath/web/02_brew/14_howto/02_clor/index.htm
>
> Excerpt:
>
> "It's necessary to regenerate it;
>
> 1)At first it's necessary to raise the acidity, adding hydrochloridic acid
> HCl (you'll find at shop as muriatic acid, mixed with water.....ask mum);
> make this work in a open place (DANGEROUS GAS) addig HCl until the muddiness
> in the tank disappears (or you can also use a litmus paper)."

I've never had that problem. I'd think it would only happen if the FeCl3 was 
undiluted (little if any water), and the HCl was stronger than the watery 
hardware shop stuff.

I started with the undiluted FeCl3 diluted with an equal amount of water, and 
now just top it up every few months with some hardware shop HCl (which has water 
in it).