Homebrew PCBs

I have used the toner transfer method with the laminator described here: http://ultrakeet.com.au/write-ups/superfuser

I have not used Press-n-peel blue, just magazine paper. However I have not had undercutting (that I ever noticed!). I used old Ferric Chloride and later on the Hydrochloric acid and Hydrogen Peroxide mixture. Both worked great.

http://ultrakeet.com.au/write-ups/etchantComparison he describes Ammonium Persulphate as being much worse than Ferric Chloride. I have never used Ammonium Persulphate.

I don't know if it's any different to Sodium Persulphate in terms of undercutting, but if his article has any truth behind it I would probably try something else.


--- In Homebrew_PCBs@yahoogroups.com, "phil.quinton@..." <phil.quinton@...> wrote:
>
> Hi,<br><br>First post, hopefully one of many..<br><br>To cut a long
> story short, I'm having problems <b>after</b> etching with Sodium
> Persulphate 

<Snip>

In short, it appears to be etching <b>under</b> the
> toner somehow.<br></blockquote><br>My guess is that the etch tank is no
> longer getting to the right temperature ( ~ 45 degrees ) and I'm etching
> too long with the agitator on. I'm going to get myself a temperature
> probe to confirm.<br><br>Has anyone had a similar experience ( Etch
> looking fine until the toner is removed )?<br><br>Thanks in
> advance,<br>Phil.<br>
>