Homebrew PCBs

How do you do your vias with this scheme? soldered bits of wire?

On Wed, Feb 22, 2012 at 11:25 AM, Harvey White <madyn@...> wrote:

> **
>
>
> On Wed, 22 Feb 2012 00:12:34 -0500, you wrote:
>
> >I think Harvey is saying expose, develop, and etch the top board first for
> >the top layer. Then do the same for the second board for the bottom layer.
> >Lastly glue/laminate the two boards together.
> >
> >
> >
> >My question is, what is being used to glue the boards together? Epoxy,
> >repreg? Any good recommendations for a glue that is easy to spread over a
> >whole board, low cost, and available? Prepreg does not seem to fit the
> >available part.
>
> I use 1 hour epoxy, in the "large" size. Costs about 15 dollars or
> so, you'll get a feeling of how much epoxy to use. Too thin a coat
> and you don't get full adhesion. You want the 1 hour because doing a
> number of boards can take longer than you think. Same full strength
> cure time for all varieties (24 hours).
>
> Use old board trimmings to spread the epoxy, but make sure that you do
> not contaminate the "new" epoxy with any old epoxy, apparently cures
> much quicker than you thought. Putting the masking tape on (avoid
> transparent scotch tape) avoids epoxy fingerprints on the board.
>
> I've tried:
>
> 1) superglue... works, but rather expensive and not as good as I might
> like.
>
> 2) shorter curing epoxy... cures too quickly, rushed jobs....
>
> have not tried:
>
> 1) carpet tape: hard to position and I'd be worried about the glue
> jamming and breaking the carbide bits
>
> 2) contact cement: same as carpet tape.
>
> Harvey
>
>
> >
> >
> >
> > _____
> >
> >From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@...m
> ]
> >On Behalf Of tda7000
> >Sent: Wednesday, February 22, 2012 12:03 AM
> >To: Homebrew_PCBs@yahoogroups.com
>
> >Subject: [Homebrew_PCBs] Re: Printers not making pattern opaque enough for
> >UV process
> >
> >
> >
> >
> >
> >--- In Homebrew_PCBs@yahoogroups.com
> ><mailto:Homebrew_PCBs%40yahoogroups.com> , Harvey White <madyn@...>
> wrote:
> >>
> >> On Wed, 22 Feb 2012 02:27:45 -0000, you wrote:
> >>
> >> >Recently I had my first try at a UV-exposed board
> >> >
> >> >(because I have nightmares from trying to align paper properly for a
> >double-sided board with the laminator, ha ha)
> >> >
> >>
> >> I figured that one out, or at least, got it very close to right.
> >>
> >> use half thickness board, prepare each side individually. Make sure
> >> that there are three alignment holes, each at a corner, leaving out
> >> one corner (keeps the board from being reversed).
> >>
> >> I use map push pins and a slightly smaller drill. You want a thick
> >> pin so it does not get pushed side to side by misalignment.
> >>
> >> Harvey
> >
> >Why half-thickness board? How do you get the board into a laminator with
> >push-pins in it? I am not sure I understand how this would work, can you
> >please explain?
> >
> >
> >
> >
> >
> >[Non-text portions of this message have been removed]
> >
> >
> >
> >------------------------------------
> >
> >Be sure to visit the group home and check for new Links, Files, and
> Photos:
> >http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> >
> >
> >
>
>  
>


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