Homebrew PCBs

made from two draws (from a roadside garbage dump) sawn in half and 
epoxied together. No form of collimation whatsoever, can do .007" 
tracks and spacing with ease. Uses standard daylight bulbs, takes 5 
minutes per side for proper exposure using positive pre-sensitized 
boards ($3.38 each for double sided 6"X4"). I can go from print to 
etched board in less than 30 minutes. You just cannot get this sort 
of workflow or board quality from TT. TT is something for the 
absolute novice IMO....Which was me 5 years ago.

http://www.pbase.com/eldata/image/52321530
http://www.pbase.com/eldata/image/52321539



--- In Homebrew_PCBs@yahoogroups.com, "mikezcnc" <eemikez@c...> 
wrote:
>
> Les, I agree that that is the ultimate method of making PCBs 
> but...you forgot to mention follwing problems:
> 1. You must have a good UV exposure box-- let's not start another 
> dicussioon today what that means. It is not a trivial issue 
although 
> for some it might be. The issue here is the resolution because I 
have 
> seen a keproo UV box for $500 failing to give a good resolution on 
> TSOP- it was all FUXXY! On quality PCB material, too.I will only 
> state that depending what you are building, the uv light may or 
may 
> not work for some or many applications. And let's not expose to 
sun 
> light for a while either :)
> 
> 2. Once you have the box you need to calibrate the bloody box and 
> depending what light it uses the timing might be all over the map, 
> depending on the preheated condition of the lamp. Depending on 
what 
> you are using. Calibration alone is not for weak people either.
> 
> 3. PCB material: buy ready made (expensive), use negative or 
positive 
> (explain it to a nenwcomer), apply film, make your own secret 
> emulsion, dry, spray, develop (how long, oops, lets strip it and 
do 
> it again, and again... what teh hell is that today...). Then 
finally 
> comes etching which is trivial..
> 
> Now, I am waiting for someone to say that he is happy with scratch 
> and etch or printing directly on copper!
> 
> Overall, I know that UV is best, and I know it works fine because 
I 
> have the whole process prepared when... when I get tired of TT-ing 
> PCBs. So far I don't foresee it. Stick a secret Staples paper in 
the 
> laser printer, hit 'print' and pull the paper out of the printer. 
> etch it and remove the paper. Then you drill.  No adjustment 
process, 
> no secret uv boxes.  Mike
>