Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, "Ben" <bhleavi@...> wrote:
>
> --- In Homebrew_PCBs@yahoogroups.com, "Leon" <leon355@> wrote:
> >
> > ----- Original Message ----- 
> > From: "derekhawkins" <eldata@>
> > To: <Homebrew_PCBs@yahoogroups.com>
> > Sent: Monday, February 05, 2007 7:55 PM
> > Subject: [Homebrew_PCBs] Re: Photo exposure
> > 
> 
> I have to agree that positive photo method if far easier and better 
> than TT.  I read on here what some seem to go thru to do the TT 
> method to get good results.  I find the positive photo method much 
> much easier.  I guess if you don't do this much TT might be a way to 
> go but if you do boards very often and have a place you can setup a 
> exposure frame and a etching tank you can produce boards very easily 
> with better results.  For most it seems that TT method is hit and 
> miss on getting a good board as can be seen in the photo of that one 
> post.  I know that there or some on here that seem to really have 
> the TT method down and have good results, but I have a idea that it 
> took them a while to get to that point too.
> 
> Ben
>

Hey Ben, Thanks for the note on the yellow inkjet for UV ... that's
interesting. I wouldn't have guessed that yellow would be better than
black???

I agree, I've seen some really good TT examples that make it tempting
but it seems a lot of people really struggle with it. I tried it a few
years ago with the Pulsar TT that is easily available from DigiKey. My
results were always about the same, about 98% effective. There were
always a few spots that the toner just didn't bond well to. I also
usually got some etching at the edges. The photo process never did
this and the learning curve is only a couple of boards. Once the
exposure time is dialed in, the rest is pretty straight forward. 

I like the one tip of printing 2 artworks and then stacking them. I'm
going to give that a shot with the laser. Should eliminate pinholes
100%. Going to try the 

btw - Just switched to DipTrace myself. So far I like it. If you
really wanted yellow, there's a program out there called GC-Prevue.
It's a gerber viewer (the viewer is free) and I think it would allow
selecting different colors for printing. Only hitch is it requires a
gerber and there's no gerbers in the free DipTrace.
Bert