Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan" 
<stefan_trethan@...> wrote:
>
> I was wanting to try silicone paper for resist transfer again.
> As i see it the problem i have is that there is not enough toner to 
cover  
> the copper fully.
> With the inkjet paper the white residue left behind probably 
helps with  
> covering it.
> 
> I thought my old HP IIID made a darker image, but actually it 
is slightly  
> lighter than the lexmark M412 on darkest setting.
> 
> So, holding the prints against a light, i can see translucence on 
all  
> traces that have any width (say 1mm).
> 
> Now i wonder, is there any model of printer that will print a 
totally  
> opaque image?
> I tried printing twice but the registration is severely off.
> 
> I'd really like it if i could use silicone paper for 
resist transfers,  
> since it works so great with legend.
> 
> Thanks
> 
> ST
>

I mentioned this in another thread: I believe that color laser 
printers/photocopiers have a different kind of black toner than 
monochrome ones. I've tried dozens of different types of printers, and 
only the color ones had a dense, opaque black. I have not seen as many 
results from home color lasers, but I would assume they would also be 
like this. A color laser needs to have nice, dense glossy colors in 
order for copies of photos, etc, to look nice. A monochrome printer is 
less likely to be used for anything but text, and on paper, you won't 
notice the density difference. Color printers also tend to have a 
higher resolution, making the pattern less jagged.

I used to use press'n'peel with a Xerox monochrome laser printer (I 
have also used it with Canon and HP ones) and even with the extra 
layer of blue from this, there would still be pitting on the etches. 
I've switched to a color laser photocopier, and just with the toner 
alone, there's only about 1/8th as much pitting, if I used green TRF 
I'm sure it would go down to zero. The only problem with color lasers 
is that they tend to run quite a bit warmer than black and white ones, 
so you have to be sure whatever you're running through it isn't going 
to melt.