Subject: Re: [Homebrew_PCBs] what is sulfate of zinc and acidulated water andsaturated copper sulfate crystals ?
From: Rob <roomberg@...> Date: 2017-01-17
I was asking a chemistry question here on HOMEBREW_PCBs because we have a number of VERY toxic processess that we use to etch PCBs and we often had chemists drop in and give us directions and safety advice.
I use the off the shelf hardware store muriactic acid for etching. I believe it is 30% hydrochloric acid mixed with 70% water
and I use the off the shelf drug store hydrogen peroxide which is 3% peroxide and 97% water.
So when I mix 100 millileters of peroxide with 50 millileters of muriactic acid I end up with a lot of water and a pretty safe chmical that has successfully etch 50 PCBs for me so far without any toxic incident.
I would never have learned that here if it were not for the chemists.
Thank you chemists.
On 01/17/2017 05:20 AM, 'David C. Partridge' david.partridge@... [Homebrew_PCBs] wrote: