Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, "Brian Chapman"
<cornbeltroute@a...> wrote:
...> 
> Uh, TT? As you can tell, I'm pretty new at all this.

Toner Transfer. See Links. Basically you print laser printer onto a
carrier (plain paper, magazine pages, special films, lots of things
have been tried and work) and it is heat pressed onto the blank
copper. Depending on the paper used, it is either peeled or soaked and
rubbed off, leaving the toner stuck onto the copper as etch resist.
Acetone or fingernail polish remover wipes the toner right off after
etching.

> > I use Think and Tinker film, and had a hell of time till I did: 1) 
> use a 10% methanol pre-spray, 2) got a good laminator 3) used a 
> carrier. As a last resort: Bubbles can be popped, and then put the 
> board back thru the laminator. I have not had bubbles or streaks or 
> rips since I did the above. <
> 
> Jeremy, is methanol available over the counter at, say, a drug store? 
> Methanol and water mix? I'm using a Regal laminator, and when I 
> finally began using a carrier the resulting resist-covered plates 
> were improved. I've tried a light spray of water, but I'll certainly 
> give the methanol approach a try next time I etch.

Hmmm... I know it as a fuel additive. Ironically, it's added to
Ethanol to make Denatured alcohol, so-called because it's toxic with
the addition of Methanol.

> > Very interesting that Epson Durabrite inks stick to a laser 
> transparency. I'd have not thought it was possible! <
> 
> With the C84, one of the "paper" options is transparency film. The 
> C84 Durabrite ink works extremely well with the LGN translucent paper 
> I mentioned. Also, the C84 resolution appears finer than the output 
> from my 1200 dpi HP laser. Is this possible?

Except on every other printer (which also have "transparency"
settings) it assumes inkjet transparency, which is specially coated to
hold the ink.

The C84 has variable drop size, much smaller than the default fixed
size of a toner dot. Also, your HP laser may be "enhanced resolution
1200dpi", meaning it's really 600dpi but they pull some tricks to get
slightly better resolution.

> > power spray etching tank that I built (from Randy Gordon-Gilmore's 
> online plans) <
> 
> >> Do you have a link? If so, it'd be great if you could put it in 
> the Links section. <<
> 
> You bet. I put the URL in Links > Photoresist etching > Build a Power 
> Spray Etching System.

Thanks!

> > I just got this link from another list, it discusses printer 
> resolution and why 288 lpi is the right raster image resolution to 
> send to a printer with a stated resolution of 720dpi or a multiple of 
> that:
> http://www.rags-int-inc.com/PhotoTechStuff/Epson2200/ <
> 
> I'm looking forward to exploring this link later today.

Keep in mind if you are printing from a vector image, don't worry
about resolution of the file.

Steve