Homebrew PCBs

Thanks. That's really helpful. I have dry film, but I've never got good
results.

Regards,
Marko


Simao Cardoso pravi:
>  
>
> Marko Pavlin wrote:
> > I retrofited famous "Peach" to Peach Vario with variable distance
> > between rollers. I made new side walls and improved gears with
> > additional holders.
>
> Very ingenious and simple your spring load system! Thanks for sharing.
>
> You said it's only for toner transfer use, but since you are doing it,
> almost from scratch, with a few extra tricks you can make it as good for
> dry film as the real expensive ones. The hot rubber rolls seem to
> already have a diameter large enough. But for dry film the rolls should
> run free. Without motor attached. The motor is attached to a second pair
> of normal rubber rolls.
>
> The dry film is viscous not solid, if traction is applied with the
> pressure and temperature, the dry film can wrinkle. Mega and other
> vendors sell GBC laminators modified only to hold the big dry film
> rolls. And those laminators are known for wrinkle the dry film in a
> stressful way. Bungard sells a super expensive laminator from a glass
> etching vendor which has the hot rubber rolls running free.
>
> The hot rolls shouldn't drive the movement, they should be driven by the
> dry film movement. The hot rubber rolls should only apply pressure and
> temperature. The second pair of normal rubber rolls drives them all,
> moving pcb with dry film already applied. The 3rd thing is the dry film
> roll stands, which as a 'brake' thing, needing some force necessary to
> pull dry film, making dry film always stretched in the hot rubber rolls.
> The brake system is made by a multiplying transmission between dry film
> roll and the roll that remove the undercover sheet. Since can't exist
> different speeds for each roll, it can't run, but the transmission has a
> clutch which let it run after a minimum force used (Except the simple
> implementation works so bad, but they seem to changed the design in
> newer models).
>
> Since no homebrew need big dry film rolls. It can be made by Adam
> Seychell good way. Having two plastic plates (upper and lower) at 45�
> with pcb movement, in which a piece of dry film is hold by water surface
> tension, nicely stretched. If a loose end of dry film is left in the hot
> roll front, when the user push a pcb through it should grab the dry film
> too, hopefully aligned.
>
> Hope to have helped anyone interested.
>