Hulatt, Jon wrote:

> Previously I've mostly made SS pcb's at home with very good results. Last
> couple have been double sided, but I'm still having problems getting the 2
> sides properly aligned. My last effort was "good enough", but I'm still
> destroying half of the pad on the opposite side when I drill the really
> small pads (like for my 4 vias).
>
> I use presensitised board, and laser printed transparency and a homemade UV
> box.
>
> How do other people align the transparency on either side?
>

What about drilling the holes in the pcb before etching?
Of course it is easier if you have access to NC machine but here is a
possible method if you don't.

1) Print the holes layer of your pcb on a sheet of paper;
2) spray a thin coat of artist glue onto the copper clad and lay
    the sheet of paper without any wrinkles and air bubbles;
3) drill all the holes;
4) Clean the paper off the clad.

I have used this method for folding metal sheet to make prototypes and
it works great.

Let me know how it works for holes.
Gaston

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