I do boards with the toner xfer down to 10 mil (.010) trace thickness. No errors, shorts or dropouts. Doublesided as well. Surface mount devices etc. With 805 smd parts acting as jumpers is normal.
0) When cutting the PCB from your stock sheet, USE AN ACRYLIC SCRIBE, carbide, hand cutting tool, along both sides of the board. A metal ruler keeps the cut dead straight. Then snap it off. No bending warping or dust. If u desire go to a sign shop and let em cut it for u.
1) u need semi decent paper, like from an Oprah or Astronomy mag. Not the super cheap mags with easily wrinkled soft paper. Don't use paper with dark pics on it
2) Setup the Laser printer for heavy print, maximum darkness, max contrast.
3) Scrub the copperclad board with dishwashing liquid and a nylon pot scrub, until its real shiny.
4) Rinse clean and pat dry with LINT FREE cloth or bounty
5) Do not handle with bare fingers, handle edges only.
6) Stick the PCB Toner pattern face down on the copper with masking tape at the edges only. These edges should not have important traces underneath.
7) Iron on by:
a) Allowing the board to come to temp without shocking it with a super hot IRON.
b) Bring iron up to hot cotton temps AFTER the board is preheated.
c) Apply Iron from different directions and press along the edge of the iron, sliding the iron completely across the board repeatedly.
d) If u get a hot air pocket on your paper, puncture with a pin and iron again.
8) I also run my boards thru a laminator 3 or 4 times at max temp after the iron on.
9) Allow board to cool before soaking in water for 15 minutes.
10) Under running water slowly peel off the soggy paper, rubbing with your thumbs to remove the sticky spots.
11) If u have a mistake use a toothpick and nail polish to repair 'opens', or an exacto blade to remove shorts.
Etch board in Dilute Nitric acid....you can see the etching process with this...better than ferric chloride and better for the environment. 3 parts water to 1 part conc. nitric. Always add acid to water. Rinse with water when done. Mix turns blue as it is used up. When nearly opaque at 2" depth...discard.
12) Keep board damp to drill, I rub water on it to prevent dry out during drilling.
Cut board to size with a Tin Snips...no sawing or dust.
13) Sand board with 220 grit wet/dry paper to remove drill burrs. Pass your fingers on it to be sure it's smooth.
14) Clean all toner off with pure Acetone (nail polish remover - no scent etc.)
15) Using a standard pencil/pen eraser scrub the board with the 'pen' eraser (blue part of a (Staedtler eraser) before soldering.
Here's a pic of my most recent board...it's double sided, using mostly 10 mil traces, the heavy traces are the power supply section. Etched but not yet cleaned of toner.
There are a few more steps if u want to align a double sided board.
Both board sides after etch. 10 mil detail, Surface mount parts, down to 603 size components. 805 size components can jumper the traces.
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