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Please help - photo resistant pcb develop

Please help - photo resistant pcb develop

2002-09-22 by stuart.lamble@batepro.co.za

Hi All

Please help. I purchased a piece of pre treated photo resistant pcb.
I removed the black protective layer and exposed my positive onto the board
by placing it in direct sunlight.
After 1 hr, I removed the positive and had a perfect image of my pcb design
on the pcb.
This is when it starts to go wrong.
I then placed the board in pre-made / purchased etching solution / ferro
chloride.
After much time, nothing has been etched.
What am I doing wrong?
Have I missed out something?



Stuart

Re: [Homebrew_PCBs] Please help - photo resistant pcb develop

2002-09-22 by Russell

stuart.lamble@... wrote:
>
> Hi All
>
> Please help. I purchased a piece of pre treated photo resistant pcb.
> I removed the black protective layer and exposed my positive onto the board
> by placing it in direct sunlight.
> After 1 hr, I removed the positive and had a perfect image of my pcb design
> on the pcb.
> This is when it starts to go wrong.
> I then placed the board in pre-made / purchased etching solution / ferro
> chloride.
> After much time, nothing has been etched.
> What am I doing wrong?
> Have I missed out something?

Yes. You're meant to put the board in developer.

Re: [Homebrew_PCBs] Please help - photo resistant pcb develop

2002-09-22 by derryck@ntlworld.com

From: stuart.lamble@...

>After much time, nothing has been etched
>What am I doing wrong?
>Have I missed out something?

You should have developed the image with sodium hydroxide solution.

I prefer the ready-made developer, but you can try a teaspoon of Caustic Soda in
a pint of water. It's pretty nasty stuff.

Wearing rubber gloves, stick your exposed board in the solution and scoosh it
about - you'll soon see when it's done.

Rinse it and then etch it.

Regards, Derryck