Homebrew PCBs

Like you, I often don't have a ground plane. I've found that 'direct etch' works well only with 1/2 oz copper. 

With 1 oz copper you are looking at 8 to 10 minutes of rubbing to clear an index card sized board on one side. That's still bit faster than an agitated bath, but its also a whole lot more work.

I'd rather throw the board in a bath, leave and come back in 10 minutes than stand there and rub continuously for 10 minutes.

Regards,
Royce


--- In Homebrew_PCBs@yahoogroups.com, "jimofc300" <jim@...> wrote:
>
> 
> Hi,
> 
> In my PCB adventures, I finally got a good transfer. I should have
> followed my own rule: "Follow the manufacturer's directions until you
> really know what you're doing, and probably after that, too." I
> deviated, though. To help someone in a similar level of novicehood, I
> detail what didn't work. I then have a question or two.
> 
> First, I used Pulsar Toner Transfer Paper, printed on my HP P1005. I ran
> it through the GBC H-64 laminator twice, per Pulsar's recommendation. In
> the water bath to lift off the TTP paper, the traces floated away, too.
> I was told here that I didn't use enough laminator passes. All
> subsequent trials used 8-10 passes. This trial went off to the Acetone
> bath. (About the only thing that worked perfectly for me.)
> 
> Next, still with TTP, I followed a recommendation here to just place the
> Green TRF foil on the board and smooth it out rather than folding over
> the end of the board. That was a disaster! The Green TRF foil wrapped
> itself around the top roller on the very first pass. Don't try this at
> home. kids! Oh, well. It's not the first time I've had to diassemble new
> equipment to fix it. Back to the acetone bath.
> 
> Then I had the hair-brained idea of using HP Presentation Paper instead
> of Pulsar TTP. Maybe others succeeded with it, but I wound up with a
> white film on top of the toner which wouldn't come off with rubbing or
> water. Apparently, some of the paper fibers stuck to the toner image.
> Acetone bath again! First question: I now have all this surplus HP
> Presentation Paper. Will it work as good, light photo or brochure paper
> on an inkjet printer? Are there any other uses for the HP paper? (I
> don't have a color laser.)
> 
> Finally, I used Pulsar TTP with Green TRF, following Pulsar's directions
> except for 8-10 passes through the laminator plus two passes for the
> Green TRF. It worked! There are a couple spots that the Green TRF
> missed; I'll try a Sharpie on them before etching.
> 
> I intend to try Pulsar's recommended "Direct Etch" method for etching.
> Basically, it entails putting Ferric Chloride on a sponge and rubbing
> off the copper as if cleaning a tabletop. No etching tank!
> 
> Questions to hopefully avoid more errors: Has anyone tried the Direct
> Etch method? Does it work? Any hints? This, my first board, has no
> ground plane and will need a lot of copper removed. Any hints on that?
> The second board I have in mind does have a ground plane, leading to
> minimal copper removal. Can anyone comment on which board style (minimum
> copper or maximum copper) is likely to give better results? Any
> difference in technique?
> 
> Thanks,
> 
> Jim
>