Well, I just scanned the boards and posted the image in the files
section -- PCB-Friday001.jpg. Have a look, they turned out pretty
darn good.
Don't be alarmed by the burn marks, let me explain what you are
seeing.
After drilling all the holes, I printed out some transfers for the
silk screen artwork and transferred them to the component side of
the boards. One of the boards in the image show this. I then
realized making a two sided board is going to be pretty tough, but I
have a better idea of that now.
I then went about Derek's tinning process with the solder paste. I
have a number of butane powered torches so I thought I would give
that a try, I wouldn't recommend it. The heat is too focused and
hard to control. The heat gun, works much better, but you have to
keep it moving or you get burns like you see in the photos. The
burns are not as bad as they look in the scan, I think the shiny tin
sections threw off the brightness/contrast settings making it look
worse than it really is.
The tinning again went pretty easy. You can see that some areas are
heavier than others and some areas could have used a tad more heat
to get it to flow out. I would wager to say that getting the
lighting just right will greatly improve this part of the process.
Seeing what is going on is kind of tough - there is some smoke, but
not much. While heating the solder paste, you can see it melt and
turn shiny - this is part of the problem with seeing what is going
on. If you have a bright light on the far side and you are sort of
looking towards it, it blinds you a bit (like looking at a bright
light does).
I believe I have even got everything mirror imaged and oriented
correctly this time too. However, while drilliing the holes I
realized another error in my circuit - I forgot to put a resistor in
for the power indicator LED. You will see the repair as a large
drilled hole "breaking a trace" and on either side two smaller holes
to put in the resistor.
Well, I guess that's another lesson learned and another club to
join :-)
If anyone has questions, feel free to ask, sooner rather than later
as I know I will start forgetting everything I did :-(
Chris
--- In
Homebrew_PCBs@yahoogroups.com, "lcdpublishing"
<lcdpublishing@y...> wrote:
> Check it out!
>
> In the files section, look for heatguntoner001.jpg it's a scan of
the
> board after etching. The scan does not show the glossy toner
effect
> from the heat gun. I looked at it with a loupe before etching and
the
> toner did look like it blended together pretty good (my eyes are
not
> the best, but it did look pretty good). The etching again, went
very
> good. Tomorrow I will wash off the toner to see what the copper
looks
> like but I suspect it is going to be pretty crisp looking. Under
the
> loupe, it appears as though I should have etched for another
minute,
> but it is pretty darn good looking so far.
>
> I don't want to remove the toner in case there is something wrong,
> don't want another "IFU" to sleep on :-)
>
> Chris