Re: PCB Artwork transfer
Wendy and David,
One problem I had for years on my home grown pcb's , I was never happy with the quality of the holes, that have a whitish look due to the rough fibreglass and often spayed out at the edges lifting up the copper foil on the hole perimeters, exactly like some of the holes on the pcb shown in post #13.
When I have my pcb maker do the pcb, their tools somehow create perfectly smooth edge holes. Or they are plated through. I bought the "hole plating" kit from RS to try, it works by lining the hole with a thin metal sleeve, it is more useful for repairs than making a hobby pcb.
I've tried a number of pcb drill types and drill speeds, in the end though the only practical way I could find at home to make the holes good was a three step pass, typically an initial drill with 0.60mm, then 0.65mm then 0.7mm to get the holes looking clean and no splaying of the pads around the holes edges (photo attached). Of course it takes three times as long to do it ! so probably only a lunatic would bother doing it, but it works.
Hugo.
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