Ratio of Ferric Chloride to copper?
2012-11-21 by RickS
Does anyone know the ratio of needed Ferric Chloride by volume to the volume of copper being removed? I am assuming 110F for the acid and constant agitation. Thanks in advance, Rick Sparber
Thread
Ratio of Ferric Chloride to copper?
Re: Ratio of Ferric Chloride to copper?
2012-11-23 by smilingcat90254
hmmm... can't really go by volume of FeCl3 (Ferric chloride) and volume of copper. Wht you need to know is how many moles of each (chemists way of counting number of atoms or molecules) will react together. read about atomic weight, Copper weighs 29gram/mole whereas FeCl3 weighs 77g/mole. And now you want to know how much ferric chloride can "eat" copper. It takes two molecules of ferric chloride to "eat" one atom of copper and turn it into one molecule of Copper chloride (CuCl2). I think it was... So you need 154g of ferric chloride to etch 29g of copper. You have to know the concentration of your ferric chloride solution. BTW, ferric chloride isn't an acid, its a salt like sodium chloride (table salt). hope this answers your question. --- In Homebrew_PCBs@yahoogroups.com, "RickS" <rgsparber@...> wrote:
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> > Does anyone know the ratio of needed Ferric Chloride by volume to the volume of copper being removed? I am assuming 110F for the acid and constant agitation. > > Thanks in advance, > > Rick Sparber >
RE: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
2012-11-23 by MIKE DURKIN
It does wondrous things to blood ... fixes the copper in hemoglobin and you suffocate .... don't drink (Duhh ) ... don't splash it on ya ... etc. Be safe ... Mike To: Homebrew_PCBs@yahoogroups.com
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From: smilingcat@earthlink.net
Date: Fri, 23 Nov 2012 02:51:25 +0000
Subject: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
hmmm... can't really go by volume of FeCl3 (Ferric chloride) and volume of copper. Wht you need to know is how many moles of each (chemists way of counting number of atoms or molecules) will react together. read about atomic weight, Copper weighs 29gram/mole whereas FeCl3 weighs 77g/mole.
And now you want to know how much ferric chloride can "eat" copper.
It takes two molecules of ferric chloride to "eat" one atom of copper and turn it into one molecule of Copper chloride (CuCl2). I think it was...
So you need 154g of ferric chloride to etch 29g of copper.
You have to know the concentration of your ferric chloride solution.
BTW, ferric chloride isn't an acid, its a salt like sodium chloride (table salt).
hope this answers your question.
--- In Homebrew_PCBs@yahoogroups.com, "RickS" <rgsparber@...> wrote:
>
> Does anyone know the ratio of needed Ferric Chloride by volume to the volume of copper being removed? I am assuming 110F for the acid and constant agitation.
>
> Thanks in advance,
>
> Rick Sparber
>
[Non-text portions of this message have been removed]Re: Ratio of Ferric Chloride to copper?
2012-11-23 by smilingcat90254
As a rule of thumb, transition metal salt such as copper chloride are very toxic. DO NOT pour it down the drain. Neutralize it first with sodium carbonate. Excess HCl reacts with carbonate to form table salt, water and CO2. But the toxic copper chloride is still there. Evaporate out the water to get copper chloride salt then when you have enough, take it to haz-mat recycling. California hazardous roundup was pretty good. take any "household" toxic material no questions asked. Label it clearly so they know what they got :) The people collecting most likely have no clue when you hand over copper chloride solution. They'll just thank you and take it from your hand. and be sure to add mixture of spent containers like herbicide container (round up), used car oil, old paint, paint thinners... And be very safe with the stuff. Just because you can make it at home so easily doesn't mean its not that toxic. smilingcat --- In Homebrew_PCBs@yahoogroups.com, MIKE DURKIN <Patriot121@...> wrote:
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> > It does wondrous things to blood ... fixes the copper in hemoglobin and you suffocate .... don't drink (Duhh ) ... don't splash it on ya ... etc. Be safe ... > > Mike > > To: Homebrew_PCBs@yahoogroups.com > From: smilingcat@... > Date: Fri, 23 Nov 2012 02:51:25 +0000 > Subject: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper? > > > > > > > > > > > > > > > > > > > > > > > > > > > hmmm... can't really go by volume of FeCl3 (Ferric chloride) and volume of copper. Wht you need to know is how many moles of each (chemists way of counting number of atoms or molecules) will react together. read about atomic weight, Copper weighs 29gram/mole whereas FeCl3 weighs 77g/mole. > > > > And now you want to know how much ferric chloride can "eat" copper. > > It takes two molecules of ferric chloride to "eat" one atom of copper and turn it into one molecule of Copper chloride (CuCl2). I think it was... > > > > So you need 154g of ferric chloride to etch 29g of copper. > > > > You have to know the concentration of your ferric chloride solution. > > > > BTW, ferric chloride isn't an acid, its a salt like sodium chloride (table salt). > > > > hope this answers your question. > > > > --- In Homebrew_PCBs@yahoogroups.com, "RickS" <rgsparber@> wrote: > > > > > > Does anyone know the ratio of needed Ferric Chloride by volume to the volume of copper being removed? I am assuming 110F for the acid and constant agitation. > > > > > > Thanks in advance, > > > > > > Rick Sparber > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] >
Re: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
2012-11-23 by Russell Shaw
On 23/11/12 18:54, smilingcat90254 wrote: > As a rule of thumb, transition metal salt such as copper chloride are very > toxic. DO NOT pour it down the drain. Neutralize it first with sodium > carbonate. Excess HCl reacts with carbonate to form table salt, water and > CO2. But the toxic copper chloride is still there. > > Evaporate out the water to get copper chloride salt then when you have > enough, take it to haz-mat recycling. California hazardous roundup was pretty > good. take any "household" toxic material no questions asked. Label it > clearly so they know what they got :) The people collecting most likely have > no clue when you hand over copper chloride solution. They'll just thank you > and take it from your hand. and be sure to add mixture of spent containers > like herbicide container (round up), used car oil, old paint, paint > thinners... > > And be very safe with the stuff. Just because you can make it at home so > easily doesn't mean its not that toxic. It makes extremely good weed killer. It will leave a black spot on the lawn, but it recovers after a few weeks. Drain unblocker/root-killer for toilets is copper sulphate, and is also sold as moss killer in gardening shops. Ferric Chloride is also known as Profloc F here, and is used as a floculating agent for sewer treatment.
Re: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
2012-11-23 by John Anhalt
First off, you seem to have confused atomic number, which is the number of protons in the atom, with atomic weight. The atomic weight of copper is 63.5 and the atomic weight of FeCl3 is 162 (molecules have no atomic number). More important, you need to define the equation, You seem to be using this equation: 2FeCl3 + Cu ===> 2FeCl2 + CuCl2 Certainly, that is one appropriate equation. But are there others? How can you explain that CuCl2 itself can be used to etch copper? Is it possible that some of the ferrous (II) chloride could be converted to an iron oxide, thus leaving more chloride to form copper chloride? Or, perhaps, the copper chloride converts to copper (II) oxide, which also releases chloride? Also, remember that copper has two oxidation states that, so Cu2O and CuO are both possible. When doing etching, particularly if there is excess HCl, several reactions are occurring. Simply, the chemistry involves oxidation, so oxygen in the solution can also play a part, and in the presence of excess HCl, oxygen can play a large part. The article by Adam Seychell has been referenced here before times and is posted on the site. He explains how CuCl2 can be used as an etchant and be continuously regenerated by bubbling air through the solution with occasional addition of HCl. Finally, when people refer to ferric chloride as an acid, remember there are different definitions for acids. When dissolved in water, ferric chloride produces and acidic solution. As for the original question, don't worry about the ratio of ferric chloride to copper. Some people actually just sponge it on and get quite rapid etching. The advantage of sponging is that exposure to oxygen is maximized. Others spray the ferric chloride, which is also a rapid method. Another method is to put both the PCB and ferric chloride in a plastic bag and squish it around. If you use a bath to immerse the PCB for etching, remember that the concentration of ferric chloride in the bath will be about 40%. If you have 1 oz copper clad for your PCB, that is 1 oz of copper per square foot. Only some of that is removed. So, it is unlikely you could ever run into a situation of having too little ferric chloride assuming you have sufficient liquid present to cover the board. John
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----- Original Message -----
From: smilingcat90254
To: Homebrew_PCBs@yahoogroups.com
Sent: Thursday, November 22, 2012 9:51 PM
Subject: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
hmmm... can't really go by volume of FeCl3 (Ferric chloride) and volume of copper. Wht you need to know is how many moles of each (chemists way of counting number of atoms or molecules) will react together. read about atomic weight, Copper weighs 29gram/mole whereas FeCl3 weighs 77g/mole.
And now you want to know how much ferric chloride can "eat" copper.
It takes two molecules of ferric chloride to "eat" one atom of copper and turn it into one molecule of Copper chloride (CuCl2). I think it was...
So you need 154g of ferric chloride to etch 29g of copper.
You have to know the concentration of your ferric chloride solution.
BTW, ferric chloride isn't an acid, its a salt like sodium chloride (table salt).
hope this answers your question.
--- In Homebrew_PCBs@yahoogroups.com, "RickS" <rgsparber@...> wrote:
>
> Does anyone know the ratio of needed Ferric Chloride by volume to the volume of copper being removed? I am assuming 110F for the acid and constant agitation.
>
> Thanks in advance,
>
> Rick Sparber
>
[Non-text portions of this message have been removed]Re: Ratio of Ferric Chloride to copper?
2012-11-23 by smilingcat90254
me bad yes you are right. It's atomic weight one should be using. This is what happens late at night. :embarassed: The reaction as I understand it is two fold. FeCl3 + Cu --> FeCl2 + CuCl then FeCl3 + CuCl --> FeCl2 + CuCl2 so the end game you get is 2FeCl3 + Cu --> 2FeCl2 + CuCl2 using correct atomic weight we need 324g of FeCl3 to etch away 63.5g of copper. not sure how copper chloride can continue to react with copper... maybe it has to do with Keq value. Partial dissociation and if you have excess [Cl] then I could see that the solution is trying to get to the equilibrium of [Cu++], [Cu+]... Pchem and statistical thermodynamics in college was oh so many years ago. Too long ago. I ended up being an electrical engineer instead. :embarassed: went from Applied physics (then two mile id happened) changed to chem e (then Bopal India with Union Carbide happened) so ended up as electrical engineer. wink wink :D --- In Homebrew_PCBs@yahoogroups.com, "John Anhalt" <janhalt@...> wrote:
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> > First off, you seem to have confused atomic number, which is the number of protons in the atom, with atomic weight. The atomic weight of copper is 63.5 and the atomic weight of FeCl3 is 162 (molecules have no atomic number). > > More important, you need to define the equation, You seem to be using this equation: > > 2FeCl3 + Cu ===> 2FeCl2 + CuCl2 > > Certainly, that is one appropriate equation. But are there others? How can you explain that CuCl2 itself can be used to etch copper? Is it possible that some of the ferrous (II) chloride could be converted to an iron oxide, thus leaving more chloride to form copper chloride? Or, perhaps, the copper chloride converts to copper (II) oxide, which also releases chloride? Also, remember that copper has two oxidation states that, so Cu2O and CuO are both possible. When doing etching, particularly if there is excess HCl, several reactions are occurring. > > Simply, the chemistry involves oxidation, so oxygen in the solution can also play a part, and in the presence of excess HCl, oxygen can play a large part. > > The article by Adam Seychell has been referenced here before times and is posted on the site. He explains how CuCl2 can be used as an etchant and be continuously regenerated by bubbling air through the solution with occasional addition of HCl. > > Finally, when people refer to ferric chloride as an acid, remember there are different definitions for acids. When dissolved in water, ferric chloride produces and acidic solution. > > As for the original question, don't worry about the ratio of ferric chloride to copper. Some people actually just sponge it on and get quite rapid etching. The advantage of sponging is that exposure to oxygen is maximized. Others spray the ferric chloride, which is also a rapid method. Another method is to put both the PCB and ferric chloride in a plastic bag and squish it around. If you use a bath to immerse the PCB for etching, remember that the concentration of ferric chloride in the bath will be about 40%. If you have 1 oz copper clad for your PCB, that is 1 oz of copper per square foot. Only some of that is removed. So, it is unlikely you could ever run into a situation of having too little ferric chloride assuming you have sufficient liquid present to cover the board. > > John > > ----- Original Message ----- > From: smilingcat90254 > To: Homebrew_PCBs@yahoogroups.com > Sent: Thursday, November 22, 2012 9:51 PM > Subject: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper? > > > > hmmm... can't really go by volume of FeCl3 (Ferric chloride) and volume of copper. Wht you need to know is how many moles of each (chemists way of counting number of atoms or molecules) will react together. read about atomic weight, Copper weighs 29gram/mole whereas FeCl3 weighs 77g/mole. > > And now you want to know how much ferric chloride can "eat" copper. > It takes two molecules of ferric chloride to "eat" one atom of copper and turn it into one molecule of Copper chloride (CuCl2). I think it was... > > So you need 154g of ferric chloride to etch 29g of copper. > > You have to know the concentration of your ferric chloride solution. > > BTW, ferric chloride isn't an acid, its a salt like sodium chloride (table salt). > > hope this answers your question. > > --- In Homebrew_PCBs@yahoogroups.com, "RickS" <rgsparber@> wrote: > > > > Does anyone know the ratio of needed Ferric Chloride by volume to the volume of copper being removed? I am assuming 110F for the acid and constant agitation. > > > > Thanks in advance, > > > > Rick Sparber > > > > > > > > [Non-text portions of this message have been removed] >
RE: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
2012-11-25 by Rick Sparber
I was looking for a rough estimate. We were starting with fresh ferric chloride for each 3" x 4" board and now see that it was not necessary. Maybe a better question is - is there a simple test to know when the ferric chloride is spent? Maybe put a single, very fine copper wire in the solution and time how long it takes to vanish? Thanks, Rick -----Original Message----- From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] On Behalf Of smilingcat90254 Sent: Thursday, November 22, 2012 7:51 PM To: Homebrew_PCBs@yahoogroups.com Subject: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper? hmmm... can't really go by volume of FeCl3 (Ferric chloride) and volume of copper. Wht you need to know is how many moles of each (chemists way of counting number of atoms or molecules) will react together. read about atomic weight, Copper weighs 29gram/mole whereas FeCl3 weighs 77g/mole. And now you want to know how much ferric chloride can "eat" copper. It takes two molecules of ferric chloride to "eat" one atom of copper and turn it into one molecule of Copper chloride (CuCl2). I think it was... So you need 154g of ferric chloride to etch 29g of copper. You have to know the concentration of your ferric chloride solution. BTW, ferric chloride isn't an acid, its a salt like sodium chloride (table salt). hope this answers your question. --- In Homebrew_PCBs@yahoogroups.com, "RickS" <rgsparber@...> wrote: > > Does anyone know the ratio of needed Ferric Chloride by volume to the volume of copper being removed? I am assuming 110F for the acid and constant agitation.
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> > Thanks in advance, > > Rick Sparber
RE: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
2012-11-25 by Rick Sparber
Smilingcat, I added a small amount of baking soda to the ferric chloride so it would not bubble over the container. Then came back in a few hours and repeated it. The stuff is slowly turning into a solid. I will label it and take to a toxic waste collection point. I have been shaking as much of the ferric chloride off of the board as I can and then rinsing it with the garden hose away from the copper water pipe. Hopefully that won't poison the ground too much. It is all crushed rock around that area so don't want anything growing there anyway. I don't see any stains on the rock. Rick
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-----Original Message----- From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] On Behalf Of smilingcat90254 Sent: Friday, November 23, 2012 12:55 AM To: Homebrew_PCBs@yahoogroups.com Subject: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper? As a rule of thumb, transition metal salt such as copper chloride are very toxic. DO NOT pour it down the drain. Neutralize it first with sodium carbonate. Excess HCl reacts with carbonate to form table salt, water and CO2. But the toxic copper chloride is still there. Evaporate out the water to get copper chloride salt then when you have enough, take it to haz-mat recycling. California hazardous roundup was pretty good. take any "household" toxic material no questions asked. Label it clearly so they know what they got :) The people collecting most likely have no clue when you hand over copper chloride solution. They'll just thank you and take it from your hand. and be sure to add mixture of spent containers like herbicide container (round up), used car oil, old paint, paint thinners... And be very safe with the stuff. Just because you can make it at home so easily doesn't mean its not that toxic. smilingcat
RE: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
2012-11-25 by David Griffith
On Sat, 24 Nov 2012, Rick Sparber wrote: > I was looking for a rough estimate. We were starting with fresh ferric > chloride for each 3" x 4" board and now see that it was not necessary. Maybe > a better question is - is there a simple test to know when the ferric > chloride is spent? Maybe put a single, very fine copper wire in the solution > and time how long it takes to vanish? A better model would be a 1cm square of scrap pcb material. -- David Griffith dgriffi@... A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?
RE: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
2012-11-25 by Rick Sparber
Would that be a blank piece of board or with some test pattern on it? Rick
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-----Original Message----- From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] On Behalf Of David Griffith Sent: Saturday, November 24, 2012 6:06 PM To: Homebrew_PCBs@yahoogroups.com Subject: RE: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper? On Sat, 24 Nov 2012, Rick Sparber wrote: > I was looking for a rough estimate. We were starting with fresh ferric > chloride for each 3" x 4" board and now see that it was not necessary. > Maybe a better question is - is there a simple test to know when the > ferric chloride is spent? Maybe put a single, very fine copper wire in > the solution and time how long it takes to vanish? A better model would be a 1cm square of scrap pcb material. -- David Griffith dgriffi@... A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail? ------------------------------------ Be sure to visit the group home and check for new Links, Files, and Photos: http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
RE: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
2012-11-25 by Rick Sparber
John, My chemistry is pathetic but I do appreciate the practical advice ;-) Rick
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-----Original Message----- From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] On Behalf Of smilingcat90254 Sent: Friday, November 23, 2012 11:12 AM To: Homebrew_PCBs@yahoogroups.com Subject: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper? me bad yes you are right. It's atomic weight one should be using. This is what happens late at night. :embarassed: The reaction as I understand it is two fold. FeCl3 + Cu --> FeCl2 + CuCl then FeCl3 + CuCl --> FeCl2 + CuCl2 so the end game you get is 2FeCl3 + Cu --> 2FeCl2 + CuCl2 using correct atomic weight we need 324g of FeCl3 to etch away 63.5g of copper. not sure how copper chloride can continue to react with copper... maybe it has to do with Keq value. Partial dissociation and if you have excess [Cl] then I could see that the solution is trying to get to the equilibrium of [Cu++], [Cu+]... Pchem and statistical thermodynamics in college was oh so many years ago. Too long ago. I ended up being an electrical engineer instead. :embarassed: went from Applied physics (then two mile id happened) changed to chem e (then Bopal India with Union Carbide happened) so ended up as electrical engineer. wink wink :D --- In Homebrew_PCBs@yahoogroups.com, "John Anhalt" <janhalt@...> wrote: > > First off, you seem to have confused atomic number, which is the number of protons in the atom, with atomic weight. The atomic weight of copper is 63.5 and the atomic weight of FeCl3 is 162 (molecules have no atomic number). > > More important, you need to define the equation, You seem to be using this equation: > > 2FeCl3 + Cu ===> 2FeCl2 + CuCl2 > > Certainly, that is one appropriate equation. But are there others? How can you explain that CuCl2 itself can be used to etch copper? Is it possible that some of the ferrous (II) chloride could be converted to an iron oxide, thus leaving more chloride to form copper chloride? Or, perhaps, the copper chloride converts to copper (II) oxide, which also releases chloride? Also, remember that copper has two oxidation states that, so Cu2O and CuO are both possible. When doing etching, particularly if there is excess HCl, several reactions are occurring. > > Simply, the chemistry involves oxidation, so oxygen in the solution can also play a part, and in the presence of excess HCl, oxygen can play a large part. > > The article by Adam Seychell has been referenced here before times and is posted on the site. He explains how CuCl2 can be used as an etchant and be continuously regenerated by bubbling air through the solution with occasional addition of HCl. > > Finally, when people refer to ferric chloride as an acid, remember there are different definitions for acids. When dissolved in water, ferric chloride produces and acidic solution. > > As for the original question, don't worry about the ratio of ferric chloride to copper. Some people actually just sponge it on and get quite rapid etching. The advantage of sponging is that exposure to oxygen is maximized. Others spray the ferric chloride, which is also a rapid method. Another method is to put both the PCB and ferric chloride in a plastic bag and squish it around. If you use a bath to immerse the PCB for etching, remember that the concentration of ferric chloride in the bath will be about 40%. If you have 1 oz copper clad for your PCB, that is 1 oz of copper per square foot. Only some of that is removed. So, it is unlikely you could ever run into a situation of having too little ferric chloride assuming you have sufficient liquid present to cover the board. > > John > > ----- Original Message ----- > From: smilingcat90254 > To: Homebrew_PCBs@yahoogroups.com > Sent: Thursday, November 22, 2012 9:51 PM > Subject: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper? > > > > hmmm... can't really go by volume of FeCl3 (Ferric chloride) and volume of copper. Wht you need to know is how many moles of each (chemists way of counting number of atoms or molecules) will react together. read about atomic weight, Copper weighs 29gram/mole whereas FeCl3 weighs 77g/mole. > > And now you want to know how much ferric chloride can "eat" copper. > It takes two molecules of ferric chloride to "eat" one atom of copper and turn it into one molecule of Copper chloride (CuCl2). I think it was... > > So you need 154g of ferric chloride to etch 29g of copper. > > You have to know the concentration of your ferric chloride solution. > > BTW, ferric chloride isn't an acid, its a salt like sodium chloride (table salt). > > hope this answers your question. > > --- In Homebrew_PCBs@yahoogroups.com, "RickS" <rgsparber@> wrote: > > > > Does anyone know the ratio of needed Ferric Chloride by volume to the volume of copper being removed? I am assuming 110F for the acid and constant agitation. > > > > Thanks in advance, > > > > Rick Sparber > > > > > > > > [Non-text portions of this message have been removed] > ------------------------------------ Be sure to visit the group home and check for new Links, Files, and Photos: http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
Re: [Homebrew_PCBs] Re: Ratio of Ferric Chloride to copper?
2012-11-25 by Russell Shaw
On 25/11/12 11:22, Rick Sparber wrote: > I was looking for a rough estimate. We were starting with fresh ferric > chloride for each 3" x 4" board and now see that it was not necessary. Maybe > a better question is - is there a simple test to know when the ferric > chloride is spent? Maybe put a single, very fine copper wire in the solution > and time how long it takes to vanish? Just keep etching PCBs until the etching time takes more than 15mins. Add HCl acid (and water if it seems too viscous). If that doesn't help, you'll have to dispose. If you add the HCl and use air bubbling agitation, you should get CuCl etching with times of 12mins or less.
Re: Ratio of Ferric Chloride to copper?
2012-11-25 by Dave Sage
David:
I see your little gripe about top posting. I would just like to point out
that I subscribe to the daily digest of the forum and when I "Reply to
Group" it opens my email editor with a clean sheet. It's the system that
puts my reply at the top. The top isn't so bad anyway. When you read the
digest (or even directly on the forum) when the next comment is at the top
just below the title I don't need to scroll through all the stuff I've
already read to follow along.
Anyway, it's sort of the toilet seat argument all over again.
Sage
[Non-text portions of this message have been removed]