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Vinyl cutter to make PCBs

Vinyl cutter to make PCBs

2004-03-29 by Steve

I just made another board using my vinyl cutter.

No way to make the center holes, and I did not want to take the time
to drill, so I am doing this the surfacemount DIP way. In other words,
no holes, components on copper side as if SMT but they are full size
with the leads clipped slightly longer than flush and soldered down.

Last time I used some very old "junk" sign vinyl. It was hard to weed,
and very difficult to remove requiring lots of Goo Gone.

This time I used some from a brand new roll. It weeded very easily,
laid down beautifully, and came off with my fingernails and rubbing
with my fingers. Weeding does still take a bit of time.

The boards don't even have to be very clean. I just gave them a quick
scrub with a bit of a non-lanolin soap and a scrubby pad. The only
issue is that of any resist, that of undercutting. Well, and make sure
there is -no- dust or hair on the board or it'll etch under the vinyl.

I doubt this would work well for SMT, and definitely can't do traces
between IC pins, but for simple single sided DIP boards, it is pretty
easy. I'll amend that: SMT up to 4 pins could probably be done, but I
doubt an 8 pin IC could be done this way. Although since the vinyl
cost me about $2 for a yard x 18 inches, I can spare a 2 inch long
piece to try. ;')

I am scanning the board and uploading it.

Next I plan on connecting my HP flatbed plotter up and trying the
Scratch And Etch.

Steve

Re: [Homebrew_PCBs] Vinyl cutter to make PCBs

2004-03-29 by Stefan Trethan

On Mon, 29 Mar 2004 20:37:37 +0200, wrote:

> On Mon, 29 Mar 2004 18:07:15 -0000, Steve <alienrelics@...> wrote:
>
>> I just made another board using my vinyl cutter.
>>
>
Is this any faster than drawing it up with a pen?
it looks a bit crude, i would prefer TT.
But thanks for the experiment, not many have a vinyl cutter to try...


can you explain what the circuit does (if there is a www reference maybe)
dopplerRDF... hmmmm...

ST

Re: Vinyl cutter to make PCBs

2004-03-29 by Steve

--- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan
<stefan_trethan@g...> wrote:
> On Mon, 29 Mar 2004 20:37:37 +0200, wrote:
>
> > On Mon, 29 Mar 2004 18:07:15 -0000, Steve <alienrelics@y...> wrote:
> >
> >> I just made another board using my vinyl cutter.
> >>
> >
> Is this any faster than drawing it up with a pen?
> it looks a bit crude, i would prefer TT.
> But thanks for the experiment, not many have a vinyl cutter to try...

Faster? Heck yeah! That would be incredibly slow to draw with a pen,
and highly inaccurate. I suppose if you've done a lot. This way,
though, I draw it once, check it over many times, and I know each one
is correct. If I draw it I have all the normal problems with etch
resist pens and I have to check each one multiple times before etching.

I'm without a laser printer at the moment. The one I had before gave
me questionable results that were hard to solder.

I see there is a Brother laser printer at Office Max (or CompUSA?)
that is $125 after rebates. I'm too broke to buy it, though.

> can you explain what the circuit does (if there is a www reference
maybe)
> dopplerRDF... hmmmm...

Sure. It uses two antennas about 1/4 wavelength apart. They are
connected to a 2 way electronic switcher. The output of that is
connected to a narrowband FM radio (in my case an FRS radio). It
switches between the two antennas, when the transmitter is closer to
one antenna than the other, there is a phase shift on switching and
you can hear a tone in the speaker. When it is equidistant to both
antennas, there is no phase difference and hence no tone.

The audio output is fed back to this circuit board where the phase
information is used to determine if the source is closer to the right
or left antenna and displayed on a centered meter, so you get more
than just a simple null indication.

http://home.att.net/%7Ejleggio/projects/rdf/tdoa1.htm

Here's one that only gives two ambiguous nulls but is much simpler:
http://home.att.net/%7Ejleggio/projects/rdf/tdoa2.htm

I thought about building the simpler one, but these will be used by
non-nerds and the few I talked to had a hard time with the idea that
they'd know it was either directly in front or behind, but not know which.

Later I plan on making one with 4 or 8 antennas with a ring of LEDs.

We can continue this on Electronics_101.

Steve