The tutorials you find posted on the web (mostly) share one feature -
they are intended to be one time things for single prototypes.
I.E: Not considering reusable masks.
(Although a few do make that consideration.)
The home style, desktop, PCB building is one version of: "Contact Printing".
(Heck, a lot of production line PBC building is also contact printing.)
Since there is more than one KT2 out there in the world ....
The number one thing left out of the DIY home style PCB building is the use of registration marks.
But with multiple masks that need to be used at various stages of the production, aligned with Micron dimensional accuracy -
Registration marks and registration pin(ning) really should be used.
Also, very dimensionally stable (over use and over time) masks should be used.
Which leads one back into the early days of photography - when this was first solved....
Glass plate negatives(*).
or in this case:
Glass plate masks with pin registration to the item being contact printed.
Which in turn means drilled holes in the glass plates.
There is a technological background to just that part of the process itself.
Pick the correct glass -
Anneal the glass -
drill / form the glass -
toughen the glass -
NOW you can make a mask on it. (Which is fun in itself.)
The above requires controlled temperatures that exceed those you can get in a toaster oven.
**BUT**
You can build an electric furnace that will do the job from the parts of a toaster oven.
At least you can if you start with a (cheap) toaster oven that uses quartz tube heating elements.
Ref:
http://en.wikipedia.org/wiki/Annealing_%28glass%29
http://www.arrowsprings.com/html/annealing.html
600C from toaster oven parts? Yup, if your determined enough.
The quartz tube heating elements have a maximum working temperature of 1050C (2000F).
(One of the reasons these toaster ovens have the: "If food ignites ..." warning labels on them.)
More to follow (someday, RSN).
(*)
http://www.getty.edu/art/gettyguide/...ils?segid=1726