Homebrew PCBs

grantfair2001 wrote:
> The price for my Grade B, teflon stopcock 50 mL burette was $48.00
> Canadian, which equals AUD$55. 

thats what I paid :)

> 
> I will try your tentative startup procedure and see how it goes. I
> have yet to get a hydrometer but have located a Canadian source. A
> universal version Dual-Scale Hydrometer, 0.700 to 2.000 Specific
> Gravity, 0.050 Divisions, 0 to 70\ufffd Baume, 1\ufffd Division, Plain Form, is
> only C$18.00; they also have methyl orange but you have to call for a
> price, which I hope to do tomorrow.
> 
> I will keep the list posted. Your continuing flow of information is
> great and I do appreciate it and your timne and effort.
> 

thanks, you can use kitchen scales to measure out the copper 
wire. Sometimes copper wire strands are coated with lubricants 
and certain stuff. I once found a lot of floating rubbish in the 
acid once it started etching, which I think was from coatings on 
the  wire. When you get the required mass of copper, give it soak 
in a little hot dishwashing detergent or degreaser, then wet it 
with some HCl and it should go pink, then give a final rinse.

Good source for scrap copper is scrap metal recycler. All the 
scrap metal places I have ever visited have had a huge piles of 
copper power cables. They sell it at about AUD$6/kg.

The universal hydrometer you describe is probably a bit 
inaccurate for copper measurement. An error of +-0.05 is too 
high. I would recommend you get a 1.200 to 1.300 +-0.002
They sell for AUD$26 here in Australia.

Of course once you have everything up and running, you might like 
to make a mini float out of plastic that permanently sits in 
your tank. That will determine if the solution is above or below 
the 1.28 g/cm^3 level.



Adam