Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Hello,

Since encountering this group a month or so ago, I have refined my
toner transfer process to the point that I am able to reliably do 15-
mil traces. Maybe smaller. Hope so.

I'm doing a home project and have settled on PIC24F
microcontrollers. The latest version needs USB, and all the PICs
that support USB are surface mount. So I have been dragged kicking
and screaming into the 21st century.

I bought an Aoyue 968 hot-air SMD rework station and some fine
tweezers and have been having a good time scrounging parts off some
defunct computer boards - just to get used to the tool. I'm going to
need a microscope - half of these parts just look like bits of dirt!

One part I scrounged is the same package as the 24FJ256GB106
processor I'm planning to use - a 64-pin TQFP. Good LORD those pins
are small. Can Toner Transfer make boards this tight? According to
the spec sheet, the pin pitch is .5mm, or about 20 thousandths of an
inch. So the traces need to be 10 thousandths of an inch, and will
only have 10 thousandths of separation. Ouch.

- Jerry Kaidor