Homebrew PCBs

Hi all,

I had a minor disaster recently when a glass jar I'd been using for 15 years to store some of my precious dwindling stock of anhydrous FeCl3 developed a crack. It went unnoticed and as the deliquescent crystals absorbed water from the air the etchant liquified and ran all over the place causing great domestic disharmony (to put it mildly). Fortunately there was not much in the jar at the time. 

I'm down to my last half kilo of the stuff, which I've been using for the last 40 years. Ferric chloride is now impossible to obtain down here in solid form and yes, I know I'll eventually have to go to another system. I've already run some experiments with HCl/H2O2 but that's not what this post is about.

My question is, how best to store it? My last stock is in a sealed plastic bag but I don't really trust it. Does FeCl3 attach glass slowly?? The old jar looked rather corroded where it broke but had always looked fine up to now. Big glass jars are getting hard to find now too. I'm tempted to scour the supermarket for anything in a suitable jar with a plastic lid.

Oh, and if anyone knows where I can get a kilo or two of solid FeCl3 (hydrated or anhydrous, but prefer the latter) in Melbourne Australia, I'd be very grateful.

Cheers to all,

Morris

morriso2002 wrote:
>  
> 
> Hi all,
> 
> I had a minor disaster recently when a glass jar I'd been using for 15 
> years to store some of my precious dwindling stock of anhydrous FeCl3 
> developed a crack. It went unnoticed and as the deliquescent crystals 
> absorbed water from the air the etchant liquified and ran all over the 
> place causing great domestic disharmony (to put it mildly). Fortunately 
> there was not much in the jar at the time.
> 
> I'm down to my last half kilo of the stuff, which I've been using for 
> the last 40 years. Ferric chloride is now impossible to obtain down here 
> in solid form and yes, I know I'll eventually have to go to another 
> system. I've already run some experiments with HCl/H2O2 but that's not 
> what this post is about.
> 
> My question is, how best to store it? My last stock is in a sealed 
> plastic bag but I don't really trust it. Does FeCl3 attach glass 
> slowly?? The old jar looked rather corroded where it broke but had 
> always looked fine up to now. Big glass jars are getting hard to find 
> now too. I'm tempted to scour the supermarket for anything in a suitable 
> jar with a plastic lid.
> 
> Oh, and if anyone knows where I can get a kilo or two of solid FeCl3 
> (hydrated or anhydrous, but prefer the latter) in Melbourne Australia, 
> I'd be very grateful.
> 
> Cheers to all,
> 
> Morris

I think liquid ferric chloride is more commonly sold. It is quite 
concentrated at S.G of 1.47 . It won't attack glass, but breakage is 
always a danger. Store the anhydride or solutions in common polyethylene 
containers sealed air tight. Those black 5L plastic jerry cans are ok. 
Maybe for another 40 years if kept away from UV light.
How much do you want ? I'm in N.W suburbs of Melbourne , and can part 
with a few litres.


Adam

Hi Morris,
You may have some luck starting here: 
http://www.electrolube.com/docs/bprototyping.html

Hope that helps

Cheers, John

----- Original Message ----- 

From: "morriso2002" <vilgotch@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, November 02, 2009 8:39 PM
Subject: [Homebrew_PCBs] FeCl3 storage


> Hi all,
>
> I had a minor disaster recently when a glass jar I'd been using for 15 
> years to store some of my precious dwindling stock of anhydrous FeCl3 
> developed a crack. It went unnoticed and as the deliquescent crystals 
> absorbed water from the air the etchant liquified and ran all over the 
> place causing great domestic disharmony (to put it mildly). Fortunately 
> there was not much in the jar at the time.
>
> I'm down to my last half kilo of the stuff, which I've been using for the 
> last 40 years. Ferric chloride is now impossible to obtain down here in 
> solid form and yes, I know I'll eventually have to go to another system. 
> I've already run some experiments with HCl/H2O2 but that's not what this 
> post is about.
>
> My question is, how best to store it? My last stock is in a sealed plastic 
> bag but I don't really trust it. Does FeCl3 attach glass slowly?? The old 
> jar looked rather corroded where it broke but had always looked fine up to 
> now. Big glass jars are getting hard to find now too. I'm tempted to scour 
> the supermarket for anything in a suitable jar with a plastic lid.
>
> Oh, and if anyone knows where I can get a kilo or two of solid FeCl3 
> (hydrated or anhydrous, but prefer the latter) in Melbourne Australia, I'd 
> be very grateful.
>
> Cheers to all,
>
> Morris
>
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and 
> Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>

----- Original Message ----- 

From: "morriso2002" <vilgotch@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, November 02, 2009 10:39 AM
Subject: [Homebrew_PCBs] FeCl3 storage


> Hi all,
>
> I had a minor disaster recently when a glass jar I'd been using for 15 
> years to store some of my precious dwindling stock of anhydrous FeCl3 
> developed a crack. It went unnoticed and as the deliquescent crystals 
> absorbed water from the air the etchant liquified and ran all over the 
> place causing great domestic disharmony (to put it mildly). Fortunately 
> there was not much in the jar at the time.
>
> I'm down to my last half kilo of the stuff, which I've been using for the 
> last 40 years. Ferric chloride is now impossible to obtain down here in 
> solid form and yes, I know I'll eventually have to go to another system. 
> I've already run some experiments with HCl/H2O2 but that's not what this 
> post is about.
>
> My question is, how best to store it? My last stock is in a sealed plastic 
> bag but I don't really trust it. Does FeCl3 attach glass slowly?? The old 
> jar looked rather corroded where it broke but had always looked fine up to 
> now. Big glass jars are getting hard to find now too. I'm tempted to scour 
> the supermarket for anything in a suitable jar with a plastic lid.
>
> Oh, and if anyone knows where I can get a kilo or two of solid FeCl3 
> (hydrated or anhydrous, but prefer the latter) in Melbourne Australia, I'd 
> be very grateful.

Farnell should have it.

I keep my solution in a plastic bottle in an old washing up bowl, in case it 
leaks. The bowl is also used to hold very hot water to keep the etchant hot 
during manual agitation.

Leon

morriso2002 wrote:
> Hi all,
> 
> I had a minor disaster recently when a glass jar I'd been using for 15 years to store some of my precious dwindling stock of anhydrous FeCl3 developed a crack. It went unnoticed and as the deliquescent crystals absorbed water from the air the etchant liquified and ran all over the place causing great domestic disharmony (to put it mildly). Fortunately there was not much in the jar at the time. 
> 
> I'm down to my last half kilo of the stuff, which I've been using for the last 40 years. Ferric chloride is now impossible to obtain down here in solid form and yes, I know I'll eventually have to go to another system. I've already run some experiments with HCl/H2O2 but that's not what this post is about.
> 
> My question is, how best to store it? My last stock is in a sealed plastic bag but I don't really trust it. Does FeCl3 attach glass slowly?? The old jar looked rather corroded where it broke but had always looked fine up to now. Big glass jars are getting hard to find now too. I'm tempted to scour the supermarket for anything in a suitable jar with a plastic lid.
> 
> Oh, and if anyone knows where I can get a kilo or two of solid FeCl3 (hydrated or anhydrous, but prefer the latter) in Melbourne Australia, I'd be very grateful.

I bought a 40 Litre bottle of liquid ferric chloride years ago from Orica (iirc)
in Melbourne. I use it diluted 1:1 with water and a bit of HCl in a Kalex
bubble etcher:

http://kalex.net.au/index.php?module=Website&action=Text&content=1098429165312-0019&parentContent=1098424907968-1192

After etching a pcb, i put a lump of wood on it to stop evaporation.

If i use it a few months later, i put some HCl in it.

After a year of doing this, it went more green than brown, but still
etches in 15mins (no heating).

The same etchant seems to be lasting forever (CuCl etching).

Moral of story: don't throw away your etchant if you use airation bubble
etching.

Let me guess, you've been throwing away kilos of the stuff
over the years;)

--- In Homebrew_PCBs@yahoogroups.com, Russell Shaw <rjshaw@...> wrote:
>
<snip>
> > 
> > Oh, and if anyone knows where I can get a kilo or two of solid FeCl3 (hydrated or anhydrous, but prefer the latter) in Melbourne Australia, I'd be very grateful.
> 
> I bought a 40 Litre bottle of liquid ferric chloride years ago from Orica (iirc)
> in Melbourne. I use it diluted 1:1 with water and a bit of HCl in a Kalex
> bubble etcher:
> 
> http://kalex.net.au/index.php?module=Website&action=Text&content=1098429165312-0019&parentContent=1098424907968-1192
> 
> After etching a pcb, i put a lump of wood on it to stop evaporation.
> 
> If i use it a few months later, i put some HCl in it.
> 
> After a year of doing this, it went more green than brown, but still
> etches in 15mins (no heating).
> 
> The same etchant seems to be lasting forever (CuCl etching).
> 
> Moral of story: don't throw away your etchant if you use airation bubble
> etching.
> 
> Let me guess, you've been throwing away kilos of the stuff
> over the years;)
>

Guilty as charged :-( I can see I will have to get into the regeneration thing. I do have some HCl here for the money pit in the backyard and will think about how to oxygenate it - I don't have a  big bubble tank and don't really want to go down that path. I usually get very good and quick results by swabbing the board continuously to remove the insoluble oxide deposit that forms on the copper. I use a sponge swab from an art supply shop. 

Thanks to everyone who replied - particularly with the news that Farnell still sells FeCl3. It looks like the hexahydrate, but that's OK. It seems I will be able to continue using my favourite etchant for a while yet.

Morris

morriso2002 wrote:
> 
> --- In Homebrew_PCBs@yahoogroups.com, Russell Shaw <rjshaw@...> wrote:
> <snip>
>>> Oh, and if anyone knows where I can get a kilo or two of solid FeCl3 (hydrated or anhydrous, but prefer the latter) in Melbourne Australia, I'd be very grateful.
>> I bought a 40 Litre bottle of liquid ferric chloride years ago from Orica (iirc)
>> in Melbourne. I use it diluted 1:1 with water and a bit of HCl in a Kalex
>> bubble etcher:
>>
>> http://kalex.net.au/index.php?module=Website&action=Text&content=1098429165312-0019&parentContent=1098424907968-1192
>>
>> After etching a pcb, i put a lump of wood on it to stop evaporation.
>>
>> If i use it a few months later, i put some HCl in it.
>>
>> After a year of doing this, it went more green than brown, but still
>> etches in 15mins (no heating).
>>
>> The same etchant seems to be lasting forever (CuCl etching).
>>
>> Moral of story: don't throw away your etchant if you use airation bubble
>> etching.
>>
>> Let me guess, you've been throwing away kilos of the stuff
>> over the years;)
>>
> 
> Guilty as charged :-( I can see I will have to get into the regeneration thing. I do have some HCl here for the money pit in the backyard and will think about how to oxygenate it - I don't have a  big bubble tank and don't really want to go down that path. I usually get very good and quick results by swabbing the board continuously to remove the insoluble oxide deposit that forms on the copper. I use a sponge swab from an art supply shop. 
> 
> Thanks to everyone who replied - particularly with the news that Farnell still sells FeCl3. It looks like the hexahydrate, but that's OK. It seems I will be able to continue using my favourite etchant for a while yet.

The only airation i do is with the small fish-tank air pump during etching.

I've been buying dry anhydrous ferric chloride on EBay for $9 a pound.
Sorry, don't know about OZ.  Can you ship the stuff from the US?

--- In Homebrew_PCBs@yahoogroups.com, "morriso2002" <vilgotch@...> wrote:

>
> Hi all,
> 
> I had a minor disaster recently when a glass jar I'd been using for 15 years to store some of my precious dwindling stock of anhydrous FeCl3 developed a crack. It went unnoticed and as the deliquescent crystals absorbed water from the air the etchant liquified and ran all over the place causing great domestic disharmony (to put it mildly). Fortunately there was not much in the jar at the time. 
> 
> I'm down to my last half kilo of the stuff, which I've been using for the last 40 years. Ferric chloride is now impossible to obtain down here in solid form and yes, I know I'll eventually have to go to another system. I've already run some experiments with HCl/H2O2 but that's not what this post is about.
> 
> My question is, how best to store it? My last stock is in a sealed plastic bag but I don't really trust it. Does FeCl3 attach glass slowly?? The old jar looked rather corroded where it broke but had always looked fine up to now. Big glass jars are getting hard to find now too. I'm tempted to scour the supermarket for anything in a suitable jar with a plastic lid.
> 
> Oh, and if anyone knows where I can get a kilo or two of solid FeCl3 (hydrated or anhydrous, but prefer the latter) in Melbourne Australia, I'd be very grateful.
> 
> Cheers to all,
> 
> Morris
>

morriso2002 wrote:
> 
> Thanks to everyone who replied - particularly with the news that Farnell 
> still sells FeCl3. It looks like the hexahydrate, but that's OK. It 
> seems I will be able to continue using my favourite etchant for a while yet.
> 

Any particular reason you want it without water molecules ?
You have to add water for it to etch anyway.

People prefer to buy and sell a near saturated 40% (wt) solution because 
it is easier to store long term.

--- In Homebrew_PCBs@yahoogroups.com, Adam Seychell <a_seychell@...> wrote:
>
> morriso2002 wrote:
> > 
> > Thanks to everyone who replied - particularly with the news that Farnell 
> > still sells FeCl3. It looks like the hexahydrate, but that's OK. It 
> > seems I will be able to continue using my favourite etchant for a while yet.
> > 
> 
> Any particular reason you want it without water molecules ?
> You have to add water for it to etch anyway.
> 
> People prefer to buy and sell a near saturated 40% (wt) solution because 
> it is easier to store long term.

I (used to) think it's easier to store the anhydride. I started off that way a long time ago and like the exothermic reaction when it dissolves - helps to keep the solution warm. I have used the hexahydrate too and it's fine too of course :-) I tried ammonium persulfate once but there's no comparison.

Morris

>