Homebrew PCBs

I'm sure this has come up before, but I'd like to build a cheap etching tank and wanted to get some advice before I actually do it.

I was thinking of buying a good sized sheet of fairly thin acrylic from Lowes or Home Depot, cutting it up into two big pieces for the front and back of the tank, two tall but narrow pieces for the sides, and then gluing it all together with some of that plastic weld stuff. 

The idea is that the tank would be really narrow (maybe 0.2") so it wouldn't take much etchant to fill it up. I was also thinking of getting one of those "air bubble devices" (I don't know what they're actually called!) from a petstore and gluing it to the bottom of the tank with the end of the hose sealed off and a bunch of small holes poked in it to agitate the etchant. It might also be possible to put a lid on the tank and putting the air intake on the bubbler and putting it inside the tank so that the fumes aren't constantly being expelled from the tank.

What are your thoughts?

Look at graigs list, garage sales, or used material stores like ReStore (Habitat 
for Humanity) for used fish tanks, pumps and tubing.

These items should be cheap and saves you time and wondering if your built tank 
is sealed and is immune to the acids involved with etching.

Ron

 



________________________________

From: nathan_h_tna <nathan_h_tna@...>
To: Homebrew_PCBs@yahoogroups.com
Sent: Sat, January 8, 2011 9:31:36 PM
Subject: [Homebrew_PCBs] Building an etching tank?

  
I'm sure this has come up before, but I'd like to build a cheap etching tank and 
wanted to get some advice before I actually do it.

I was thinking of buying a good sized sheet of fairly thin acrylic from Lowes or 
Home Depot, cutting it up into two big pieces for the front and back of the 
tank, two tall but narrow pieces for the sides, and then gluing it all together 
with some of that plastic weld stuff. 


The idea is that the tank would be really narrow (maybe 0.2") so it wouldn't 
take much etchant to fill it up. I was also thinking of getting one of those 
"air bubble devices" (I don't know what they're actually called!) from a 
petstore and gluing it to the bottom of the tank with the end of the hose sealed 
off and a bunch of small holes poked in it to agitate the etchant. It might also 
be possible to put a lid on the tank and putting the air intake on the bubbler 
and putting it inside the tank so that the fumes aren't constantly being 
expelled from the tank.

What are your thoughts?





      

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

On Sun, 09 Jan 2011 02:31:36 -0000, you wrote:

>I'm sure this has come up before, but I'd like to build a cheap etching tank and wanted to get some advice before I actually do it.
>
>I was thinking of buying a good sized sheet of fairly thin acrylic from Lowes or Home Depot, cutting it up into two big pieces for the front and back of the tank, two tall but narrow pieces for the sides, and then gluing it all together with some of that plastic weld stuff. 

Thin plastic is not all that good.  Plastic weld may or may not work,
I don't know.  Depends on what you do.  You'll need to have something
that withstands hydrochloric acid and at 120 or so degrees, not that
it  will get that hot.  I'd plan for it, though, just because.
>
>The idea is that the tank would be really narrow (maybe 0.2") so it wouldn't take much etchant to fill it up. 

If you use Hydrogen peroxide and Hydrochloric acid, you don't need to
economize on etchant, it's cheap.

>I was also thinking of getting one of those "air bubble devices" (I don't know what they're actually called!) from a petstore and gluing it to the bottom of the tank with the end of the hose sealed off and a bunch of small holes poked in it to agitate the etchant. 

You'd be better off using a sealed aquarium air tube with little holes
drilled in it.  The glue deteriorates in Ferric Chloride after a bit,
and you're left with a little pile of sand.


>It might also be possible to put a lid on the tank and putting the air intake on the bubbler and putting it inside the tank so that the fumes aren't constantly being expelled from the tank.

Might eat the pump....

I etch outside, move the cars out of the way, etc.

I also use a relatively cheap cereal container (plastic), which has
never had a problem with the etchant, either variety.

Harvey

>
>What are your thoughts?
>
>
>
>------------------------------------
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>

An etching tank may not be necessary. See
http://www.pulsarprofx.com/pcbfx/main_site/pages/tech_support/no_etching_tank/no_etching_tank.html

I haven't tried it yet, but expect to try it in the next few days.

I tried almost exactly what you proposed except I didn't get around to
adding a bubbler - I just threaded an insulated wire through a hole in
the board and used that to dip the board in the tank, like dipping a
tea bag. The results were very unsatisfactory. The etching was slow
but faster at the edges.

On Sat, Jan 8, 2011 at 7:31 PM, nathan_h_tna <nathan_h_tna@...> wrote:
> I'm sure this has come up before, but I'd like to build a cheap etching tank and wanted to get some advice before I actually do it.
>
> I was thinking of buying a good sized sheet of fairly thin acrylic from Lowes or Home Depot, cutting it up into two big pieces for the front and back of the tank, two tall but narrow pieces for the sides, and then gluing it all together with some of that plastic weld stuff.
>
> The idea is that the tank would be really narrow (maybe 0.2") so it wouldn't take much etchant to fill it up. I was also thinking of getting one of those "air bubble devices" (I don't know what they're actually called!) from a petstore and gluing it to the bottom of the tank with the end of the hose sealed off and a bunch of small holes poked in it to agitate the etchant. It might also be possible to put a lid on the tank and putting the air intake on the bubbler and putting it inside the tank so that the fumes aren't constantly being expelled from the tank.
>
> What are your thoughts?

Thank you for that link, Jan. I would be interested in hearing of your 
results.

Bill

On 9/01/2011 2:10 PM, Jan Kok wrote:
> An etching tank may not be necessary. See
> http://www.pulsarprofx.com/pcbfx/main_site/pages/tech_support/no_etching_tank/no_etching_tank.html
>
> I haven't tried it yet, but expect to try it in the next few days.
>
> I tried almost exactly what you proposed except I didn't get around to
> adding a bubbler - I just threaded an insulated wire through a hole in
> the board and used that to dip the board in the tank, like dipping a
> tea bag. The results were very unsatisfactory. The etching was slow
> but faster at the edges.
>
>
> On Sat, Jan 8, 2011 at 7:31 PM, nathan_h_tna<nathan_h_tna@...>  wrote:
>> I'm sure this has come up before, but I'd like to build a cheap etching tank and wanted to get some advice before I actually do it.
>>
>> I was thinking of buying a good sized sheet of fairly thin acrylic from Lowes or Home Depot, cutting it up into two big pieces for the front and back of the tank, two tall but narrow pieces for the sides, and then gluing it all together with some of that plastic weld stuff.
>>
>> The idea is that the tank would be really narrow (maybe 0.2") so it wouldn't take much etchant to fill it up. I was also thinking of getting one of those "air bubble devices" (I don't know what they're actually called!) from a petstore and gluing it to the bottom of the tank with the end of the hose sealed off and a bunch of small holes poked in it to agitate the etchant. It might also be possible to put a lid on the tank and putting the air intake on the bubbler and putting it inside the tank so that the fumes aren't constantly being expelled from the tank.
>>
>> What are your thoughts?
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>

Hi Nathan

I bought a Velleman ET10 hobbyist tank at a ham radio rally (flea 
market) and paid GBP 20 for the both the tank and a UV light box :-) The 
construction is very similar to the one you propose to build:
http://www.circuitsonline.net/forum/view/36243

Included was a small aquarium aeration pump and an aquarium heater. The 
heater raises the etch temperature to about 40C. My tank is about 19mm 
(3/4" wide) and if you wanted to use a heater you'll need to make your 
DIY tank wider than 0.2" of course. Heating is a good idea, with fairly 
fresh etchant a board takes less than 10 minutes but this tank needs 2L 
of etchant as a result. I haven't found the etchant a problem in 
practice, between use I store it in an air tight jar in a cool place and 
it lasts much longer than the stated shelf life.

If you have to buy new materials plus a heater and an aquarium aeration 
pump the saving might not be very great compared to a ready made tank?

I'm not sure which country you are in but the Velleman ET20 is widely 
available and quite cheap.
http://www.velleman.eu/downloads/1/et20gbnlfresd.pdf

$55 from Circuit Specialists in the USA:
http://www.circuitspecialists.com/prod.itml/icOid/4231

Also widely available in the UK & Europe, google Velleman ET20.

If you wanted something better, in the UK Mega sell a much nicer moulded 
polyprop one for GBP 135.
http://www.megauk.com/hobby_equipment.php

There's no lid. I don't use Ferric Chloride anymore but instead I use 
the clear di-Sodium Peroxodisulphate Hexahydrate etchant sold in the UK 
by Mega Electronics. Although more expensive than Ferric Chloride it is 
a lot cleaner and nicer to handle. The etchant is odour free and the 
data sheet states that no local ventilation is required, although I do 
etch near an open window.

Regards

Paul


On 09/01/2011 02:31, nathan_h_tna wrote:
>
> I'm sure this has come up before, but I'd like to build a cheap 
> etching tank and wanted to get some advice before I actually do it.
>
> I was thinking of buying a good sized sheet of fairly thin acrylic 
> from Lowes or Home Depot, cutting it up into two big pieces for the 
> front and back of the tank, two tall but narrow pieces for the sides, 
> and then gluing it all together with some of that plastic weld stuff.
>
> The idea is that the tank would be really narrow (maybe 0.2") so it 
> wouldn't take much etchant to fill it up. I was also thinking of 
> getting one of those "air bubble devices" (I don't know what they're 
> actually called!) from a petstore and gluing it to the bottom of the 
> tank with the end of the hose sealed off and a bunch of small holes 
> poked in it to agitate the etchant. It might also be possible to put a 
> lid on the tank and putting the air intake on the bubbler and putting 
> it inside the tank so that the fumes aren't constantly being expelled 
> from the tank.
>
> What are your thoughts?
>
> 



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

In article <igb6m8+je59@...>,
   nathan_h_tna <nathan_h_tna@...> wrote:
> I was thinking of buying a good sized sheet of fairly thin acrylic from
> Lowes or Home Depot, cutting it up into two big pieces for the front and
> back of the tank, two tall but narrow pieces for the sides, and then
> gluing it all together with some of that plastic weld stuff. 

I was looking at doing that too. My existing (commercial) bubble-etch tank
is on the way out. However, investigating the chemical resistant
properties of acrylic I discovered that after a very short time, Ferric
Chloride will cause it to craze and crack.

What the experience of others on this list is, I wait to see the comments
here.

-- 
Stuart Winsor

Midland RISC OS show - Sat July 9th 2011

On Sun, 09 Jan 2011 20:53:42 +0000 (GMT), you wrote:

>In article <igb6m8+je59@...>,
>   nathan_h_tna <nathan_h_tna@...> wrote:
>> I was thinking of buying a good sized sheet of fairly thin acrylic from
>> Lowes or Home Depot, cutting it up into two big pieces for the front and
>> back of the tank, two tall but narrow pieces for the sides, and then
>> gluing it all together with some of that plastic weld stuff. 
>
>I was looking at doing that too. My existing (commercial) bubble-etch tank
>is on the way out. However, investigating the chemical resistant
>properties of acrylic I discovered that after a very short time, Ferric
>Chloride will cause it to craze and crack.

Rubbermaid or the equivalent plastic cereal container.  Takes lots of
etchant, but has never deteriorated.  Be careful with some of the
sealing rings, they disintegrate.

Worked with FeCL3 and CuCL etchants, never leaked.

Harvey

>
>What the experience of others on this list is, I wait to see the comments
>here.

In article <0b9ki6lj8pv5be7updu06b5ofkj0g90d08@...>,
   Harvey White <madyn@...> wrote:
> Rubbermaid or the equivalent plastic cereal container.

Yes, I've been keeping an eye out for that sort of thing. A lot of them
are Polypropylene, which has excellent chemical resistance, but I've not
yet found one of quite the size I would like.

-- 
Stuart Winsor

Midland RISC OS show - Sat July 9th 2011

You could do a spray tank for better results.

On 10/01/2011 06:40, Jeff wrote:
> You could do a spray tank for better results.

I tried a low-cost bubble etch tank and it was a waste of time - it took 
ages to heat up and the etching was very uneven. I get much better 
results with hand agitation with a small plastic etchant container in an 
old washing up bowl with some very hot water (just boiled) in it.

Leon
-- 
Leon Heller
G1HSM

I did exactly what you suggested about three years ago.  I scored the sheets of acrylic with a straight edge and razor blade for relatively straight and clean edges.  Then I assembled a tall, narrow tank using whatever acrylic glue is sold near the sheets of acrylic at Lowe's/Home Depot (it comes in a white/red tube and seems similar to silicone to me).

The finished tank is about 1" thick, 8" wide and 10" tall.  The bottom piece is about 8" by 8" so the tank stands upright.  I use a bubbler, check valve and pump meant for an aquarium to aerate the etchant.  I don't use FeCl anymore, just CuCl, but the tank has held up well to it.

Regards,



-Paul    


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

>
> I'm sure this has come up before, but I'd like to build a cheap etching tank and wanted to get some advice before I actually do it.
> 
> I was thinking of buying a good sized sheet of fairly thin acrylic from Lowes or Home Depot, cutting it up into two big pieces for the front and back of the tank, two tall but narrow pieces for the sides, and then gluing it all together with some of that plastic weld stuff. 
> 
> The idea is that the tank would be really narrow (maybe 0.2") so it wouldn't take much etchant to fill it up. I was also thinking of getting one of those "air bubble devices" (I don't know what they're actually called!) from a petstore and gluing it to the bottom of the tank with the end of the hose sealed off and a bunch of small holes poked in it to agitate the etchant. It might also be possible to put a lid on the tank and putting the air intake on the bubbler and putting it inside the tank so that the fumes aren't constantly being expelled from the tank.
> 
> What are your thoughts?
>

> Posted by: "Dave M" dgminala@...
> <dgminala@...?Subject=+Re%3A%20Roland%20DXY%20800%2F880>   snurfl
> <http://profiles.yahoo.com/snurfl>  Sun Jan 9, 2011 6:44 am (PST)
>
> Ridge Electronics has the manual at
> https://www.ridgeequipment.com/store/manuals/search.php?query=roland. Not
> free, but very reasonable. These guys are good vendors. I've bought many
> manuals from them; never had a problem.
>
> David
>
> ----- Original Message -----
> From: davethesteam@... <davethesteam%40mailsaq.net>
> To: Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com>
> Sent: Saturday, January 08, 2011 2:30 PM
> Subject: [Homebrew_PCBs] Re: Roland DXY 800/880
>
> Hi, I'm a new user so I'm not 100% sure how this works, so here goes: I
> have a Roland DXY-880A plotter but I can't get it to work as I don't have a
>
> manual and I have mucked-up the switch settings. Do you (or anyone) have
> anything you can send me with the DIP switch settings on, I'd be happy to
> buy a manual or photocopy if anyone has anything available. I've tried
> everywhere to get a manual or switch info and even Roland can't help. I've
> found lots of people looking though :-)
>
> TIA
>
> David
>
> --- In Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com>,
> Trevor Matthews <bigtrev97@...>
> wrote:
> >
> > I have used direct plotting to PCB in the past, and gave it up a few
> years
> > ago. I had ink flow problems which would result in the traces not being
> > draw thickly enough several times through a plot. I was using 0.35mm pen
> > (so that I could do some thin traces) and I don't know if a larger pen
> size
> > would help. I wrote a Dephi (pascal) prgram which took the plot file and
> > after a length of drawn line, inserted a number of pen up, backspace,
> pen
> > down commands to 'shake' the pen and try and get more ink to the tip.
> >
> > If you want to try here are some of the things you need to know:
> >
> > You need to use a tungsten carbide 'X' point tip (the other tips are too
> > soft)
> > the pen is raised up by the addition of a washer placed below the ring
> of
> > the pen holder - experimentation will show you how low to put the ring
> so
> > that the pen holder can pick it up, and how high to put it so that the
> pen
> > tip is still flat on the surface of the board.
> > tape a peice of paper to the bed, and plot the board to the paper
> > Tape an oversized piece of PCB over the plot drawn above.
> > Fill the pen with ink (I tried for ages to find the right one, it was a
> > steadler ink. I think I still might have some at home if you want me to
> dig
> > out the part number, but IIRR it was out of production the last time I
> > bought some)
> > Plot the board
> > clean the pen - the only way to do this close to properly is to use an
> > ultrasonic cleaning bath. I ended up dissasembling the pen while
> cleaning
> > (I'm told you shouldn't really do this!) as it could easily spent a
> couple
> > of hours in the bath with me changing the solvent every 10 mins or so.
> > then etch and protect the board as usual.\
> >
> > I eventually gave up due to the trace issue above, and I couldn't
> > translate it to double sided with any degree of accuracy.
> >
> > Trev
> >
> > On Tue, Aug 3, 2010 at 1:26 AM, <casy_ch@...> wrote:
> >
> > >
> > >
> > > Don
> > >
> > > Could you send me your private adress to <casy_ch at tbwil dot ch>. I
> have
> > > files for you.
> > >
> > > Jean-Claude
> > >
> > > ----- Original Message -----
> > > From: VK3YV
> > > To: Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com><Homebrew_PCBs%
> 40yahoogroups.com>
> > > Sent: Monday, August 02, 2010 4:23 PM
> > > Subject: Re: [Homebrew_PCBs] Re: Inkjet or Laser for PCB work?
> > >
> > > Hi Jean-Claude, that is a big help, now I need to know the DIP switch
> > > settings, I will be using the parallel port, and hopefully be able to
> use
> > > it
> > > with win xp, do you still have the dip switch settings?
> > > Many thanks,
> > > Don VK3YV........
> > >
> > > ----- Original Message -----
> > > From: <casy_ch@... <casy_ch%40tbwil.ch>>
> > > To: <Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com><Homebrew_PCBs%
> 40yahoogroups.com>>
> > > Sent: Tuesday, August 03, 2010 12:08 AM
> > > Subject: Re: [Homebrew_PCBs] Re: Inkjet or Laser for PCB work?
> > >
> > > > Hi Don
> > > >
> > > > In the past I have had a DXY800 and later a DXY1150.
> > > >
> > > > All use HPGL (Hewlett Packard Graphic Language). Your programm
> should
> > > have
> > > > a HPGL driver and will generate a <xx.PLT> file.
> > > >
> > > > If you go to:
> > > > http://en.wikipedia.org/wiki/HPGL
> > > > you will find the language it is using.
> > > >
> > > > 73 de Jean-Claude, Switzerland
> > > > HE9EZX
> > > >
> > > >
> > > > ----- Original Message -----
> > > > From: VK3YV
> > > > To: Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com><Homebrew_PCBs%
> 40yahoogroups.com>
> > > > Sent: Monday, August 02, 2010 3:02 PM
> > > > Subject: Re: [Homebrew_PCBs] Re: Inkjet or Laser for PCB work?
> > > >
> > > >
> > > >
> > > > Hi, on seeing you are using a Roland Plotter for pcb drawing I have
> a
> > > > query,
> > > > I have a Roland DXY 800 for which I have no information i.e.. dip
> switch
> > > > settings etc. that I would also like to use for PCB work. I have no
> > > > information at all about it , I don't even know what language it
> talks.
> > > > Can
> > > > any one help, I have searched for hours but cant find anything
> regarding
> > > > setup or language/ emulation .
> > > > Regards,
> > > > Don VK3YV.....
> > > >
> > > > ----- Original Message -----
> > > > From: "P COUNSELL" <pcounsell@...<pcounsell%40btinternet.com>
> > > >
> > > > To: <Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com>
> <Homebrew_PCBs%40yahoogroups.com>>
> > > > Sent: Monday, August 02, 2010 8:54 PM
> > > > Subject: Re: [Homebrew_PCBs] Re: Inkjet or Laser for PCB work?
> > > >
> > > > > Unfortunately athough I have some pens whuch were designed for
> pcbs
> > > > they
> > > > > are no longer availabe for rowland plotters. I do not see that as
> a big
> > > > > problem . I intend to use EDDING 404 PEN TIPS with edding 404
> refill
> > > > ink
> > > > > with a homemade holder. I will first try recharging my existing
> tips
> > > > when
> > > > > they run out with EDDING PERMANENT MARKER REFILL INK, I expect
> this to
> > > > > work fine.
> > > > > ----- Original Message -----
> > > > > From: P COUNSELL
> > > > > To: Homebrew_PCBs@yahoogroups.com<Homebrew_PCBs%40yahoogroups.com>
> <Homebrew_PCBs%40yahoogroups.com>
> > > > > Sent: Sunday, August 01, 2010 10:41 PM
> > > > > Subject: Re: [Homebrew_PCBs] Re: Inkjet or Laser for PCB work?
> > > > >
> > > > >
> > > > >
> > > > > I modified my DXY880a very easily by using a piece of standard pcb
> > > > board
> > > > > so that the pen height was perfect for standard thickness pcbs.
> > > > > ----- Original Message -----
> > > > > From: borgrailuk
> > > > > To: Homebrew_PCBs@yahoogroups.com<Homebrew_PCBs%40yahoogroups.com>
> <Homebrew_PCBs%40yahoogroups.com>
> > > > > Sent: Sunday, August 01, 2010 9:30 PM
> > > > > Subject: [Homebrew_PCBs] Re: Inkjet or Laser for PCB work?
> > > > >
> > > > > Hi,
> > > > >
> > > > > Sounds interesting. How did you modify the plotter pen height and
> which
> > > > > pens/ink did you use?
> > > > >
> > > > > I have a DXY1200 - not too keen to modify height but am planning
> on
> > > > using
> > > > > a slightly thinner pcb, which will fit.
> > > > >
> > > > > Stephen Freeman
> > > > >
> > > > > --- In Homebrew_PCBs@yahoogroups.com<Homebrew_PCBs%40yahoogroups.com>
> <Homebrew_PCBs%40yahoogroups.com>,
> > > "P COUNSELL" <pcounsell@>
> > > > wrote:
> > > > > >
> > > > > > I have a very good dos program CADPAK and I use an old rowland
> > > > DXY-880A
> > > > > plotter. Results are fantastic . I modified the height of the
> plotter
> > > > pen
> > > > > to accomodate standard thickness PCB board. Only problem is it
> wont do
> > > > > tracks fine enough for intertrack knecking , itis also very slow
> on
> > > > > printing directly onto the copperlaminate but I have a cup of tea.
> Fine
> > > > > for prototyping.
> > > > > > ----- Original Message -----
> > > > > > From: Bob Butcher
> > > > > > To: Homebrew_PCBs@yahoogroups.com<Homebrew_PCBs%40yahoogroups.com>
> <Homebrew_PCBs%40yahoogroups.com>
> > > > > > Sent: Tuesday, July 20, 2010 9:53 PM
> > > > > > Subject: Re: [Homebrew_PCBs] Inkjet or Laser for PCB work?
> > > > > >
> > > > > >
> > > > > >
> > > > > > I have had a lot of trouble with toner transfer as well. My
> Brother
> > > > > 1440 laser printer toner will not release reliably from any paper
> I
> > > > have
> > > > > found. I have heard the toner has a higher melting temperature
> than
> > > > some
> > > > > other printers, but am not sure what the problem is.
> > > > > > I am not sure how you plan to modify the Artisan 50 inkjet
> printer to
> > > > > directly print on the rigid PCB material. Another thing to
> consider,
> > > > most
> > > > > of the ink jet ink I have seen is water soluble, so the etchant
> will
> > > > > dissolve the ink before it has a chance. I know there are ink jet
> > > > printers
> > > > > that are capable of using solvent based inks, but all the ones I
> have
> > > > seen
> > > > > are very expensive, in the several thousands of dollar range. You
> can
> > > > buy
> > > > > inexpensive "paint pens" from art and craft stores that might be
> useful
> > >
> > > > if
> > > > > you could find a flat bed printer that could be adapted to pens. I
> have
> > >
> > > > on
> > > > > old large format HP printer designed for CAD drafting that uses
> pens,
> > > > but
> > > > > the pen only moves on one axis, and the paper is fed back and
> forth by
> > > > a
> > > > > roller system for the other axis. The paper is wrapped around the
> > > > rollers,
> > > > > so it cannot be easily adapted to a rigid PCB. If someone had a
> flat
> > > > bed
> > > > > printer with a moving pen on two axes, that might work. Sounds
> like an
> > > > old
> > > > > school
> > > > > > chart recorder might work, if you could find a working model
> that
> > > > would
> > > > > interface to a modern computer.
> > > > > >
> > > > > > Bob
> > > > > >
> > > > > > --- On Wed, 7/21/10, gnuvvekaavaali <gnuvvekaavaali@> wrote:
> > > > > >
> > > > > > From: gnuvvekaavaali <gnuvvekaavaali@>
> > > > > > Subject: [Homebrew_PCBs] Inkjet or Laser for PCB work?
> > > > > > To: Homebrew_PCBs@yahoogroups.com<Homebrew_PCBs%40yahoogroups.com>
> <Homebrew_PCBs%40yahoogroups.com>
> > > > > > Date: Wednesday, July 21, 2010, 12:22 AM
> > > > > >
> > > > > >
> > > > > >
> > > > > > I am looking for suggestions on the choice of
> > > > > >
> > > > > > Inkjet (for direct inkjet printing) or laser
> > > > > >
> > > > > > printer (toner transfer) for the occasional single sided PCB.
> > > > > >
> > > > > > I don't see I will be needing very thin or dense tracks.
> > > > > >
> > > > > > My experience with toner transfer have not been too good. I
> > > > > >
> > > > > > used a Samsung Laser printer, and a hot clothes iron,
> > > > > >
> > > > > > with different types of paper.
> > > > > >
> > > > > > Best results have been with glossy magazine paper, but still
> > > > > >
> > > > > > had some improper transfers.
> > > > > >
> > > > > > The Epson Artisan 50 inkjet seems to be moddable for direct pcb
> > > > > printing, and I can get that for cheap.
> > > > > >
> > > > > > Wondering if this is a easier and reliable way than toner
> transfer.
> > > > > >
> > > > > > [Non-text portions of this message have been removed]
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > [Non-text portions of this message have been removed]
> > > > > >
> > > > >
> > > > > [Non-text portions of this message have been removed]
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > [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
> > > > >
> > > > >
> > > > >
> > > >
> > > > ----------------------------------------------------------
> > > >
> > > > No virus found in this incoming message.
> > > > Checked by AVG - www.avg.com
> > > > Version: 9.0.851 / Virus Database: 271.1.1/3044 - Release Date:
> 08/02/10
> > > > 04:40:00
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > [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
> > > >
> > > >
> > > >
> > >
> > > ----------------------------------------------------------
> > >
> > > No virus found in this incoming message.
> > > Checked by AVG - www.avg.com
> > > Version: 9.0.851 / Virus Database: 271.1.1/3044 - Release Date:
> 08/02/10
> > > 04:40:00
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > >
> > >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
> [Non-text portions of this message have been removed]
>


Please trim old portions of posts. This get particularly bad for those of us
who get the list in digest form.

Thanks you.

Mike


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

So it sounds like building a tank will probably work, but may not be worth
it. I guess I'll have to think about it some more before deciding whether to
do it or not. I'd love to hear more input from people who have tried it
though..

Have you guys had any problem with the fumes from the HCl corroding metal in
the vicinity? I haven't noticed this, but I recently posted on a chemistry
forum and they said this would be a severe long-term problem.

I'm also curious how you protect yourselves from the fumes. When I'm etching
I *try* to do it in a fairly ventilated place, but the fumes still smell
extremely strong and I can't help wonder if I should be wearing a respirator
or something..


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

> I was looking at doing that too. My existing (commercial) bubble-etch tank
> is on the way out. However, investigating the chemical resistant
> properties of acrylic I discovered that after a very short time, Ferric
> Chloride will cause it to craze and crack.
> 
> What the experience of others on this list is, I wait to see the comments
> here.


I have used some glass fish tanks using Ferric Chloride.  It will break down the sealant over time and start to leak.  I went thru 3 tanks and decided to give up on using Fish Tanks.

Ben

> Rubbermaid or the equivalent plastic cereal container.  Takes lots of
> etchant, but has never deteriorated.  Be careful with some of the
> sealing rings, they disintegrate.
> 
> Worked with FeCL3 and CuCL etchants, never leaked.
> 


After I gave up on the Fish Tanks and using FeCL3 I now use CuCL in a Plastic Container that I keep on the back porch.  CuCL is a lot cheaper to use than FeCL3.


Ben

On Sat, 15 Jan 2011 03:35:11 -0000, you wrote:

>
>> Rubbermaid or the equivalent plastic cereal container.  Takes lots of
>> etchant, but has never deteriorated.  Be careful with some of the
>> sealing rings, they disintegrate.
>> 
>> Worked with FeCL3 and CuCL etchants, never leaked.
>> 
>
>
>After I gave up on the Fish Tanks and using FeCL3 I now use CuCL in a Plastic Container that I keep on the back porch.  CuCL is a lot cheaper to use than FeCL3.
>
>
>Ben
>
>
When I switched over from FeCl to CuCl I used the same plastic
tray with snaps on all four sides that I had used for several years.
It had a red plastic seal. A few weeks later I went to use the CuCl 
to etch another board and the cover was really loose. The CuCl 
had destroyed the seals; turned them into a white, crumbly substance. 
There was a tray containing several partially discharged batteries sitting
beside the tray. The terminals on both ends were severely corroded.

Keith Bowers WB4LSJ- Thomasville, NC

On 15/01/2011 02:56, Nathan House wrote:
> So it sounds like building a tank will probably work, but may not be worth
> it. I guess I'll have to think about it some more before deciding whether to
> do it or not. I'd love to hear more input from people who have tried it
> though..
>
> Have you guys had any problem with the fumes from the HCl corroding metal in
> the vicinity? I haven't noticed this, but I recently posted on a chemistry
> forum and they said this would be a severe long-term problem.

I've had that problem.


>
> I'm also curious how you protect yourselves from the fumes. When I'm etching
> I *try* to do it in a fairly ventilated place, but the fumes still smell
> extremely strong and I can't help wonder if I should be wearing a respirator
> or something..

They are more unpleasant than dangerous.

Leon
-- 
Leon Heller
G1HSM

On Fri, Jan 14, 2011 at 9:56 PM, Nathan House
<nathanhooyagroups@...> wrote:
>
> So it sounds like building a tank will probably work, but may not be worth
> it. I guess I'll have to think about it some more before deciding whether to
> do it or not. I'd love to hear more input from people who have tried it
> though..
>
> Have you guys had any problem with the fumes from the HCl corroding metal in
> the vicinity? I haven't noticed this, but I recently posted on a chemistry
> forum and they said this would be a severe long-term problem.
>
> I'm also curious how you protect yourselves from the fumes. When I'm etching
> I *try* to do it in a fairly ventilated place, but the fumes still smell
> extremely strong and I can't help wonder if I should be wearing a respirator
> or something..

I use the smallest fish tank (glass, with a glass top that fits into
the grooves on the top --PetsMart) I have been able to find (15 cm x
30cm/6"x12", 9.5 L), and the silicone sealant on it has held up for
many months of holding the solution without any sign of degradation.
I may have been using a weaker solution than most people use since it
does take a while to etch, but I'm not in a hurry and the fumes are
really minimal.  When I am not using it I use a plastic garbage bag
and wrap it securely around the whole tank to prevent any fumes and
have never had a problem since.

I used a partially-covered polypropylene container in a basement for a
while and the solution *was* stronger and it corroded virtually
everything in the basement area, including chrome-plated racks, steel
bar stock, and basically anything that it could attack.  The odor
itself was only really noticeable when bubbling/etching.  I no longer
trust bubblers since they by nature tend to create a fine mist of
etchant that spreads everywhere.  I now use a sacrificial fountain
pump (All of about 5-7$, smallest size) to circulate the etchant which
works very well.  The pumps last a long time as long as you don't
leave them in the etchant permanently and rinse them after etching.  I
highly recommend these type of pumps since they are very well sealed,
there is no moving part besides the magnet and generally the glue
holding the impeller to the magnet breaks down first, which is easily
repaired.  Eventually the magnet itself dissolves but that hasn't been
a problem with temporary use/rinsing.  Also great for electroplating
solutions which use similarly aggressive acids and must have
agitation.

Larry

>> Have you guys had any problem with the fumes from the HCl corroding metal
in
>> the vicinity? I haven't noticed this, but I recently posted on a
chemistry
>> forum and they said this would be a severe long-term problem.

>I've had that problem.

So how did you deal with it? Just store and use the etchant away from any
metal objects?


>> I'm also curious how you protect yourselves from the fumes. When I'm
etching
>> I *try* to do it in a fairly ventilated place, but the fumes still smell
>> extremely strong and I can't help wonder if I should be wearing a
respirator
>> or something..

>They are more unpleasant than dangerous.

Really? I guess that's good news..


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

I've not read a lot of the comments on this subject so this may already be 
covered. My two roubles worth if I may!

Part of the problem seems to be sealing submerged joints with a sealant 
which does not react to corrosive etchants.
Whatever the sealant, I thought maybe there was something else could be done 
to prevent the reaction, or at least slow it right down to a minimum. Paint 
for example.
Or better still perhaps, Shellac. (You probably know all this?)
Shellac is a PCB resist used in the past  It's quite robust and insoluable 
in water. Disolved in Methylated spirits (meths) it can be built up in 
layers by painting it on (meths evaporates much faster than it can desolve 
Shellac)

Since this is about building an eching tank, testing the materials is always 
a good idea.
This is probably what I'd go for:
Test the shellac theory first! If Shellac is worth it's salt, construct a 
"fishtank" to personal spec from glass, angle iron or aluminium using the 
most suitable sealant available. Paint any visible outside metalwork and 
exposed surfaces (except the glass) to prevent splash corrosion. Apply 
several coats of a Shelllac to the inside glass joints already sealed with a 
suitable sealant. Another possibility is Shellac varnish although I don't 
know what else it might contain besides shellac.
Every once in a while check the seals just in case. Any signs of 
deterioration, clean them up and apply another coat or two of Shellac.
I'm willing to bet several coats will last a very long time. (10p/10c in 
case I'm wrong!)
Take great care if using Meths. It is very highly inflamable with an 
invisible flame - you cannot see it to put it out!
Hope this helps.

And incidentally, Shellac can also be used to cover large areas of PCBs to 
preserve the copper. Removal is easy if you are not in a hurry! The process 
is quite painless but slow. Simply drop the etched board into Meths until it 
disolves.

One more unrelated incidental, Meths can be used to remove those ugly white 
circular stains left by hot cups on poIished tables. Wipe a small amount 
over the stain and light it. Allow a few seconds for it to burn out, or blow 
it out. Do NOT allow it to blister. Finish off with soft cloth. The heat 
will take out that stain. You might want to take the sensible approach and 
test it first.

I'm new to the group, located on the Shetland Islands (the one across the 
pond from Alaska)
Also fairly new to PCB making and no expert. Apologies for lack of 
qualifications.

Peter
MM5PSL

----- Original Message ----- 
From: kabowers@...
To: Homebrew_PCBs@yahoogroups.com
Sent: Saturday, January 15, 2011 4:10 AM
Subject: Re: [Homebrew_PCBs] Re: Building an etching tank?



On Sat, 15 Jan 2011 03:35:11 -0000, you wrote:

>
>> Rubbermaid or the equivalent plastic cereal container. Takes lots of
>> etchant, but has never deteriorated. Be careful with some of the
>> sealing rings, they disintegrate.
>>
>> Worked with FeCL3 and CuCL etchants, never leaked.
>>
>
>
>After I gave up on the Fish Tanks and using FeCL3 I now use CuCL in a 
>Plastic Container that I keep on the back porch. CuCL is a lot cheaper to 
>use than FeCL3.
>
>
>Ben
>
>
When I switched over from FeCl to CuCl I used the same plastic
tray with snaps on all four sides that I had used for several years.
It had a red plastic seal. A few weeks later I went to use the CuCl
to etch another board and the cover was really loose. The CuCl
had destroyed the seals; turned them into a white, crumbly substance.
There was a tray containing several partially discharged batteries sitting
beside the tray. The terminals on both ends were severely corroded.

Keith Bowers WB4LSJ- Thomasville, NC





No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1191 / Virus Database: 1435/3379 - Release Date: 01/14/11

I generally agree; CuCl and CuCl2 aren't too dangerous as long as your exposure to them is limited to infrequent inhalation.  Here are the MSDS for each of them if you're still concerned:  

http://www.jtbaker.com/msds/englishhtml/c5949.htm
http://www.jtbaker.com/msds/englishhtml/c5863.htm

I keep my CuCl2 in a plastic bottle with a sealing lid, like this one:

http://www.amazon.com/Rubbermaid-Servin-Saver-White-Bottle/dp/B0000CFN3O/

I used to keep all of my etching supplies in a cabinet under a sink, including the etchant and a semi-sealed, one gallon jug of HCl.  After about six months, the cabinet's hinges became thoroughly rusted.  Other metal things corroded too.  

I replaced the hinges and moved the HCl, but left the etchant, about a year ago.  Since then, the hinges have remained clean and nothing else has further corroded.  The HCl is now in an open area in my garage.  As long as it's in a non-enclosed area with adequate ventilation, it'll be fine.


-Paul

 

--- In Homebrew_PCBs@yahoogroups.com, Leon Heller <leon355@...> wrote:

>
> On 15/01/2011 02:56, Nathan House wrote:
> > So it sounds like building a tank will probably work, but may not be worth
> > it. I guess I'll have to think about it some more before deciding whether to
> > do it or not. I'd love to hear more input from people who have tried it
> > though..
> >
> > Have you guys had any problem with the fumes from the HCl corroding metal in
> > the vicinity? I haven't noticed this, but I recently posted on a chemistry
> > forum and they said this would be a severe long-term problem.
> 
> I've had that problem.
> 
> 
> >
> > I'm also curious how you protect yourselves from the fumes. When I'm etching
> > I *try* to do it in a fairly ventilated place, but the fumes still smell
> > extremely strong and I can't help wonder if I should be wearing a respirator
> > or something..
> 
> They are more unpleasant than dangerous.
> 
> Leon
> -- 
> Leon Heller
> G1HSM
>

Hmmm! New to the group and sent an email about eight hours ago. So far nothing came back!

Peter
MM5PSL
 

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

On Sat, Jan 8, 2011 at 8:10 PM, Jan Kok <jan.kok.5y@...> wrote:
> An etching tank may not be necessary. See
> http://www.pulsarprofx.com/pcbfx/main_site/pages/tech_support/no_etching_tank/no_etching_tank.html

Just tried the brushing-with-sponge technique, with excellent results.
Got very well defined 10 mil trace/spaces on a one-sided board with
1/2 oz copper. There was even a 5-mil board outline that came out
pretty well (there were breaks in the outline due to poor toner
adhesion prior to etching).

I used less than a tablespoon of 10 year old FeCl3 from Radio Shack.
It took about 5 minutes to etch using in a cold (50 degrees F) garage.
Frank Miller of Pulsonix says that it takes 45 seconds if the etchant
is hot.

The poly sponge and latex gloves I used (from Ace Hardware) seems to
be unaffected by the etchant and reusable.

Given how well this process works, I feel no need for an etching tank!

Cheers,
- Jan

Jan Kok <jan.kok.5y@...> writes:
> Frank Miller of Pulsonix says that it takes 45 seconds if the etchant
> is hot.

I've done it in 45 seconds.  To heat the etchant, I just half-fill a
small bucket with hot tap water and put the sealed etchant bottle in it,
15 minutes earlier in the process.  By the time I need it, it's just
right.

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

>
> I'm sure this has come up before, but I'd like to build a cheap etching tank and wanted to get some advice before I actually do it.
> 
> I was thinking of buying a good sized sheet of fairly thin acrylic from Lowes or Home Depot, cutting it up into two big pieces for the front and back of the tank, two tall but narrow pieces for the sides, and then gluing it all together with some of that plastic weld stuff. 
> 
> The idea is that the tank would be really narrow (maybe 0.2") so it wouldn't take much etchant to fill it up. I was also thinking of getting one of those "air bubble devices" (I don't know what they're actually called!) from a petstore and gluing it to the bottom of the tank with the end of the hose sealed off and a bunch of small holes poked in it to agitate the etchant. It might also be possible to put a lid on the tank and putting the air intake on the bubbler and putting it inside the tank so that the fumes aren't constantly being expelled from the tank.
> 
> What are your thoughts?
>Hi I built mine from a fiberglass car repair kit. make a small plug from MDF, cover it in varnish then once dry give it several coats of PVA glue,cover in resin and fiberglass, when its dry soak in water to soften the PVA and pull the fiberglass tank off, make a wooden box to sit the tank in then fill the void with spray in foam, yhis also helps to insulate the tank, atach a small aquarium pump to the box and glue a perforated hose inside the tank.

I have always used a glass baking dish with a cover as an etching tank. 
Of course if you are doing a lot of larger boards you might not find 
exactly what you need. They are not expensive.

I have read about using a zip-lock bag to etch and I plan to try that 
the next time. It sounds like a good solution that is both clean and frugal.

A lot depends on how big your boards are. Mine seem to be getting 
smaller every time.
-- 

John Ferrell W8CCW

"The same prudence which in private life would forbid our paying our own 
money for unexplained projects, forbids it in the dispensation of the 
public moneys." --Thomas Jefferson



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

>Just tried the brushing-with-sponge technique, with excellent results.

Well, maybe I should give ferric chloride a try then. It would avoid the
rust problem which I only recently learned about, is probably safer to use
(there aren't any fumes with ferric chloride, correct?). Do you just wash
off the sponge in the sink afterwords?


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

You might not want to do this in a good sink. FeCl stains like hell, even
porcelain is difficult to keep clean.
I take the rust issues, which are easily eliminated by just covering the
etchant up, any day over the mess FeCl makes.

ST

On Wed, Jan 26, 2011 at 9:41 PM, Nathan House
<nathanhooyagroups@...>wrote:

>
> Do you just wash
> off the sponge in the sink afterwords?
>
>


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

On Wed, Jan 26, 2011 at 1:41 PM, Nathan House
<nathanhooyagroups@...> wrote:
>>Just tried the brushing-with-sponge technique, with excellent results.
>
> Well, maybe I should give ferric chloride a try then. It would avoid the
> rust problem which I only recently learned about, is probably safer to use
> (there aren't any fumes with ferric chloride, correct?). Do you just wash
> off the sponge in the sink afterwords?

I did the etching while holding the board above or in a plastic
dishwashing basin. I had a 1-liter glass beaker filled with water
which I used to rinse off the board a couple times to get a better
look at the etching progress, and then in the end to rinse out the
sponge and gloves. Then carefully poured the contaminated water down
the drain, rinsed out the dishwashing basin and poured that water
carefully down the drain, then not-so-carefully rinsed everything
again in the laundry sink. I could probably do that hundreds of times
without staining anything. It was less mess than I expected, really
not much mess at all.

I noticed some fumes from the FeCl3 when I heated it in an open
beaker, but didn't notice any fumes at all when using it cold. (Not
that I put my nose close to the opening of the bottle... :-)

Cheers,
- Jan

Remember that a lot of waste lines are made of copper alloys (brass and such) and even small amounts of FeCl will etch them away over time.

Donald.
--
*Plain Text* email -- it's an accessibility issue
()  no proprietary attachments; no html mail
/\  ascii ribbon campaign - <www.asciiribbon.org>

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

> From: "Jan Kok" <jan.kok.5y@...>
> To: "Homebrew PCBs" <Homebrew_PCBs@yahoogroups.com>
> Sent: Wednesday, January 26, 2011 6:29:47 PM
> Subject: Re: [Homebrew_PCBs] Re: Building an etching tank?
> 
> On Wed, Jan 26, 2011 at 1:41 PM, Nathan House
> <nathanhooyagroups@...> wrote:
> >>Just tried the brushing-with-sponge technique, with excellent results.
> >
> > Well, maybe I should give ferric chloride a try then. It would avoid the
> > rust problem which I only recently learned about, is probably safer to use
> > (there aren't any fumes with ferric chloride, correct?). Do you just wash
> > off the sponge in the sink afterwords?
> 
> I did the etching while holding the board above or in a plastic
> dishwashing basin. I had a 1-liter glass beaker filled with water
> which I used to rinse off the board a couple times to get a better
> look at the etching progress, and then in the end to rinse out the
> sponge and gloves. Then carefully poured the contaminated water down
> the drain, rinsed out the dishwashing basin and poured that water
> carefully down the drain, then not-so-carefully rinsed everything
> again in the laundry sink. I could probably do that hundreds of times
> without staining anything. It was less mess than I expected, really
> not much mess at all.
> 
> I noticed some fumes from the FeCl3 when I heated it in an open
> beaker, but didn't notice any fumes at all when using it cold. (Not
> that I put my nose close to the opening of the bottle... :-)
> 
> Cheers,
> - Jan

> >Just tried the brushing-with-sponge technique, with excellent results.
> 
> Well, maybe I should give ferric chloride a try then. It would avoid the
> rust problem which I only recently learned about, is probably safer to use
> (there aren't any fumes with ferric chloride, correct?). Do you just wash
> off the sponge in the sink afterwords?


Ferric Chloride will rust things too.
It stains most anything it touches.
Works best when Heated.
Do you have any metal in your Drain?  Ferric Chloride eats metal.

Other than after etching it has copper disolved in it putting small amounts down a drain is not too bad, flush it with plenty of water.  Ferric Chloride is used in Waste Water Treatment.  But after you etch your boards it will have copper in it which is not all that good to go down the drain.


Ben

On 26/01/11 20:46, Stefan Trethan wrote:
> You might not want to do this in a good sink. FeCl stains like hell, even
> porcelain is difficult to keep clean.

JohnsonDiversey "Titan Sanitiser" works a treat for getting rid of FeCl 
stains. Rinse the sink out to dampen it, turn off the tap and count to 
ten. Cover the inside of the sink in the stuff (it's a powder) and rub 
it on the stains. Rinse away the remaining powder (it's water soluble).

Make sure you wear gloves! This stuff is nasty -- it's used for 
disinfecting hospital floors. If you can't get hold of it, Swarfega 
might also work. Essentially what you want is a substance which is both 
a mild abrasive and a detergent.

As long as you don't, say, wait a day between using FeCl in the sink and 
cleaning it, you should be fine.

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

In article <4D40D94B.1080709@...>,
   Philip Pemberton <ygroups@...> wrote:

> JohnsonDiversey "Titan Sanitiser" works a treat for getting rid of FeCl 
> stains. Rinse the sink out to dampen it, turn off the tap and count to 
> ten. Cover the inside of the sink in the stuff (it's a powder) and rub 
> it on the stains. Rinse away the remaining powder (it's water soluble).

Proprietry "Ferric Chloride stain remeover" is based on Oxalic acid.

-- 
Stuart Winsor

Midland RISC OS show - Sat July 9th 2011

The drain cleaning products that contain concentrated sulfuric acid work like magic on sinks stained with ferric chloride. Just put some on a damp sponge, wipe and rinse.

Baxter

--- In Homebrew_PCBs@yahoogroups.com, lists <Stuartlists@...> wrote:

>
> In article <4D40D94B.1080709@...>,
>    Philip Pemberton <ygroups@...> wrote:
> 
> > JohnsonDiversey "Titan Sanitiser" works a treat for getting rid of FeCl 
> > stains. Rinse the sink out to dampen it, turn off the tap and count to 
> > ten. Cover the inside of the sink in the stuff (it's a powder) and rub 
> > it on the stains. Rinse away the remaining powder (it's water soluble).
> 
> Proprietry "Ferric Chloride stain remeover" is based on Oxalic acid.
> 
> -- 
> Stuart Winsor
> 
> Midland RISC OS show - Sat July 9th 2011
>