TDA:
Actually, your local prices are not really that different from the price
variations we have in the States.
And, I guess, if one wanted to save a water and sodium bicarb solution,
it would be rather reasonable to do so.
But remember that the used solution will contain muriatic acid, and that
is probably something to use caution with.
I personally don't like to have a bunch of chemicals of any sort sitting
around the house, so I use a batch once
and get rid of it.
Compared to sending my PCB fab jobs out to a commercial PCB fab house,
the cost of
the once-used-then-disposed chemicals is a pittance. And besides, with
T.T., I don't
have to wait two weeks to have my circuit boards.
My containers of hydrogen peroxide and muriatic acid are kept in a
secure place.
I pay about a dollar for a quart of hydrogen peroxide, and about 5
dollars for a gallon of
muriatic acid, which is practically a household item here in southern
Arizona, where
there are so many backyard swimming pools and the acid is used for pool
cleaning.
Good luck in your toner transfer adventures.......and believe
me........perfecting the
toner transfer method is truly and adventure.
Roland F. Harriston, P.D.
tda7000 wrote:
>
>
> No worries, I can understand your point of view.
>
> However having never actually purchased any I had no idea of the
> price, nor do I live in USA and in my country (New Zealand) things can
> be a bit of a ripoff.
>
> For example, You can buy this (almost 1 litre) of hydrogen peroxide
> for $2-3
> (http://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/#step1)
> but it costs me $3.50 just for 100ml (about 10 times the price!)
>
> No local shop sells more than 100ml bottles either, you can special
> order larger ones but the price is even worse for some reason. (have
> they not heard of bulk discounts?)
>
> Take the HCl too, according to that instructable, "The acid I got is
> 31.45% (or 10M) and should run around $5 per gallon"
>
> Google tells me 1 US gallon = 3.7 litres, yet 1 litre of HCl here is
> $18. That would make 3.7 litres around $60!
>
> You don't want to know the price of liquid tin crystals! (nobody sells
> the liquid itself)- not that I buy them, of course. Some cheap flux
> and a soldering iron is what I do in the way of tinning.
>
> I don't know if the prices for your chemicals are that cheap
> everywhere in USA, so I'm sorry if I am wrong there, but in comparison
> they do not seem very cheap here.
>
> However a quick look online suggests the baking soda IS pretty cheap,
> so I guess that part wouldn't be too bad... thanks for the advice, I
> guess once you used it you couldn't use it again anyway.
>
> --- In Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com>, Roland Harriston
> <rolohar@...> wrote:
> >
> > Sometimes, I am truly amazed!
> >
> > A pound box of Arm and Hammer Baking soda costs about a dollar-fifty in
> > any supermarket in the USA.
> > Cheaper at WalMart.
> >
> > If you live in the high altitudes of Nepal or Tibet, and you have to
> > ride your yak down a mountainside to buy a box, then you might think
> > about saving
> > the cost of an ounce of bicarb.
> >
> > Sorry.........I just could not resist.
> >
> > Roland F. Harriston, P.D.
> > ∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗∗
> >
> > tda7000 wrote:
> > >
> > >
> > > Thanks - I guess then that just a water rinse isn't good enough?
> > > Also, do you re-use the baking soda mixture or make a new lot each
> time?
> > >
> > > --- In Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com>
> > > <mailto:Homebrew_PCBs%40yahoogroups.com>, "leeleduc" <leeleduc@>
> wrote:
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > One thing I should mention. I keep a bowl with about 1 quart of
> > > water and 1/4 cup of baking soda dissolved in it. When I'm done, I
> > > toss the foam brush and any tools I've used into the bowl to
> > > neutralize any acid on them. I do the same with the PCB, quick dip in
> > > the bowl and a quick rinse under the the tap and I'm good to go.
> > > >
> > > > --- In Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com>
> > > <mailto:Homebrew_PCBs%40yahoogroups.com>, "tda7000" <Tda7000@> wrote:
> > > > >
> > > > > Sounds good, I think I will try that. Like the idea of a foam
> > > brush, should be easier to use than just a kitchen sponge and less
> messy.
> > > > >
> > > > >
> > > > > --- In Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com>
> > > <mailto:Homebrew_PCBs%40yahoogroups.com>, "leeleduc" <leeleduc@>
> wrote:
> > > > > >
> > > > > > I use this technique all the time. I can do a 4X6 inch board in
> > > about 2 minutes. I use 1 Part HCL and 2 Parts 3% H2O2. I make just
> > > enough etchant to cover the board about 1/8 to 1/4 inch and lightly
> > > brush the surface with a foam Paint brush. I etch at room
> temperature.
> > > Works very well for me.
> > > > > >
> > > > > > I've also tried 1 part HCL and 2 parts 12% H2O2 but the
> reaction
> > > was too fast and hot to control easily.
> > > > > >
> > > > > >
> > > > > >
> > > > > > --- In Homebrew_PCBs@yahoogroups.com
> <mailto:Homebrew_PCBs%40yahoogroups.com>
> > > <mailto:Homebrew_PCBs%40yahoogroups.com>, "tda7000" <Tda7000@> wrote:
> > > > > > >
> > > > > > > I see some people get very fast etch times with a sponge and
> > > ferric chloride...
> > > > > > >
> > > > > > > But has anyone tried that method with the HCl and H2O2
> > > solution, or the cupric chloride?
> > > > > > >
> > > > > > > Or anything else for that matter?
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> > >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
[Non-text portions of this message have been removed]