Homebrew PCBs

On 31 Dec 2005, at 22:15, kennytrussell wrote:

> John,
> That is a nice board. At the end of your page, you mention that you
> think the tracks ended up 25 mils rather than 20 because of the
> extra toner. That is exactly what I am talking about that used to
> cause me trouble. I think you have the right idea by not applying
> too much pressure. I still apply a good bit of pressure but I make
> sure my toner is thin from the printer.

Kenny, I upped the toner density to make sure I got a solid black  
print (I have a software utility to do that on my Apple Laserwriter).

I get a good solid black I can feel with my fingers is raised, but I  
do tend to get small pad centre holes after ironing on, to the point  
of the hole disappearing at times, so I think your idea of going the  
other way and using less toner may be good. I am using a Staedtler  
Lumocolor pen to touch up any little bits that need it. I am using  
the black pen 318-9 and it works. I have read that the only one to  
use is the red version of the pen, but black seems OK to me.

All laser printers print heavier than they should. I often see  
printouts that come out of a 600 dpi laser side by side with output  
from a 1270 dpi or 2540 dpi Linotron typesetter and the difference is  
huge.

I did my first double-sided board 2 days ago (yes another clock, but  
much smaller) and it seemed to work OK. I drilled four holes in the  
corners and lined up the second side with the holes. I got it a bit  
out of true, but not enough that the board was useless. I had no  
trouble ironing on one side and then doing the other. I had imagined  
the back might re-melt and smear.

John