how many PCB's from PNP Blue sheet?

Started by powerplayj, June 04, 2005, 03:57:33 PM

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powerplayj

I thinking of etching my own boards.  About how many PCB's can you get out of one sheet of Press N' Peel blue?  I'm guessing my initial transfers will be 3" X 4" before I cut off the excess??? (or does that sound too large?)

Also, what size copper clad board is best?  I was looking at this one from Small Bear.  http://www.smallbearelec.com/Detail.bok?no=65

The projects I have in mind are BSIAB2, Rebote Delay 2, Dyna-Ross Comp and possibly an Axis Fuzz or a Vibe
builds completed: boutique fuzz, rangemaster, BSIAB2, PT-80, Tonepad wah, Ross Comp, Axis Fuzz, MOSFET boost, Thunderchief, Big Muff (triangle), Mr. EQ, Dr. Boogey,  Neovibe, Dist+, EA Tremelo, ADA Flanger, RM Octavia
next build(s): ???

Mark Hammer

You can easily snag 10 PCB patterns off a sheet if you're careful.  Given the possibility of mistakes, though, it's probably a good idea to make 2 copies of each pattern.  If the first one bombs, you have a backup, and if the first one is a keeper, you have something to give a hobby buddy that they will deeply appreciate, or a second copy of the pedal you can monkey around with.

I find the best thing to do is to print up copies of the patterns you want, trim them down with scissors, tape them to a backing sheet and make a photocopy or scan of THAT to use for your master.  Realistically, a lot of patterns aren't a whole lot bigger than maybe 1.5" x 3'" once the unessentials are eliminated.

powerplayj

Thanks Mark!

Will the PCB boards that Small Bear sells be fine for my transfers?
builds completed: boutique fuzz, rangemaster, BSIAB2, PT-80, Tonepad wah, Ross Comp, Axis Fuzz, MOSFET boost, Thunderchief, Big Muff (triangle), Mr. EQ, Dr. Boogey,  Neovibe, Dist+, EA Tremelo, ADA Flanger, RM Octavia
next build(s): ???

Mark Hammer

I think you can safely assume so, since it's us that he caters to.  Just make sure your hands are squeaky clean, keep them off the board as much as you can, and that you have some extra fine steel wool handy to buff the copper to a gleaming shine.  The smoother the copper, the better the transfer.

brett

I make most boards about 2 inches x 2 inches, to fit the slots in the "Taiwanese" boxes.  That means I get about 20 projects out of 1 sheet!!
QuoteThe smoother the copper, the better the transfer.
Mark's right on the money here (as usual).  I went through a period when I was slack about board cleanliness.  My success rate went from 99% to 90%.  Those buggered-up 10% are REALLY annoying.

I use fine sandpaper (around 400 to 800 grit) or glasspaper (OO) to clean/smooth the PCB, then just before I apply the PnP, I rub it down with toothpaste (yes, toothpaste) and rinse off with clean water.

good luck.
Brett Robinson
Let a hundred flowers bloom, let a hundred schools of thought contend. (Mao Zedong)