There are some good Instructables on using toner transfer, but after doing my own for a while I have some refinements on the process that I want to share. You should be able to create high-quality, well aligned double sided boards every time.
If you are just dealing with a basic board for 0.1" pitch through hole components this is probably overkill. A good instructable for those kinds of boards this one by pinomelean.
I have made excellent boards with 8 mill pads and 12 mill clearances.
There are a few secrets. 1. a laser printer. 2. a hot laminator. 3. (The big secret) Parchment cooking paper. 4. Careful and diligent cleaning of the board.
If you follow my directions to the letter you can get great results.
Step 1: Gather supplies and materials
Laminator. Digikey part number 182-1031-ND. $114 at time of writing.
- MCUman says "Harbor Freight sells a 9" laminator for 30 bucks. I've had mine for a couple of years now, I use it often, and it works GREAT! Item number 92499."
Laser printer. Mine is an HP LaserJet P1102w.
- dasclown says a Dell 5100 cn laserjet did not work.
- If you know of one that does/does not work, comment please.
- Scotch Bright sponge
- etching "tank"
- Leather gloves for handling the hot board (or a towel, or your shirt. It's not that hot.)
- Sewing needles
- Alligator clip wires
- Drill press or dremel and tiny drill bits needed for your design. Harbor Freight sells a cheap multi pack of tiny bits.
- Glass cook top cleaner
- Tarn-X tarnish remover
- Parchment paper from the grocery store
- heavy duty zip top bags
- Kapton tape (1/4" is best) - no substitutions!
- 1/2oz x 1/16th" copper board
- Stranded copper wire. Something with fairly thin strands. Jumper wires the cat chewed in half work good. (See photo 3)
- Rubber gloves
- Muratic Acid (or Acid Magic from Ace Hardware)
- Hydrogen peroxide
- glass measuring vessel
- plastic/wood utensils
- ecthing "tank" - Pyrex dish
- rinsing tank