Info: Making own PCB at home.

Making own PCB at Home

What you should know????

While making PCB's at home isn't particularly difficult, it's not a trivial undertaking. You need to acquire some kind of PCB layout program, and build or buy some specialized equipment. There's also a bit of a learning curve to it, especially the PCB layout tool. There's nothing stopping you from using resist-pen, or even a simple computer paint program to define the traces. The downside is that this will limit you on the complexity of the circuit you can lay out, and make it harder to incorporate changes down the line. Moreover something wrong in the procedure may increase your cost. Good thing is its equipment are mostly one time buy for some who needs to make PCB regularly and immediately.

Equipment Required

Depending on how resourceful you are, you can spend a little or a lot on etching equipment. Using what's known as the "toner transfer method", where you print your board layout onto a special paper using a laser printer, then "re-fuse" the toner onto a blank copper board using a laminating machine. Then you soak the paper off, leaving the toner behind. The etchant can't eat through the toner, so any copper covered with toner remains behind as circuit traces or component pads. Seems simple, and it is. But there are a few gotchas that will make or break the success of this process.

The Process

Step 1.

The first step is to transfer the schematic to the schematic capture part of the layout program.

Step 2.

After the schematic is entered, the PCB layout program
is used to place the parts on the board and route the copper
traces.

Step 3.

After the first few parts are routed, the "ratsnest"
begins to clear up. If you're lucky, you get a PCB that
requires no external jumper wires.

Step 4.

When the layout is done, the board layers are printed

onto special toner transfer paper with a laser printer.
This board "image" is transferred to the bare copper board
with a laminating machine, or a hot clothes iron.

Step 5.

After laminating, the board with the paper stuck to it
is soaked to remove the paper, leaving only the toner behind.

Step 6.

Below is a photo of the raw copper board with toner
remaining, after the transfer paper has been soaked off.

Step 7.

Inside the etch tank, two aquarium pumps circulate etchant
(Ammonium Persulfate) over the copper boards while two
aquarium heaters keep the solution at 110F.This process can take
anywhere from 10-30 minutes depending on the freshness of the
solution and thickness of the copper.

Step 8.

After etching, the toner is removed with solvent and the board is tinned using a soldering iron and a small piece of tinned solderwick. Tinning isn't absolutely necessary but it improves the appearance of the board, and prevents the copper from oxidizing before it's time to solder the parts to the board.