Step 1 : Important information

Prepare to read the standard disclaimer:

Firstly: The steps outlined in this HowTo are merely for educational purposes. This is by no means the only way to make printed circuit boards. It’s the way I know how and it works for me. For other ways/methods, check out the photo fabrication area at http://www.mgchemicals.com/ (Thanks Russell Watson)

Secondly: Perform the steps outlined here carefully! Bad things happen to good people when you least expect it. The etchant used in this procedure is a corrosive acid (ferric chloride) and should be handled with care. It will permanently stain and ruin any fabric it comes in contact with. It's none too easy to get off your hands either so use of rubber gloves is recommended. It will also corrode any metal it comes in contact with so don't use your nice needle nose pliers to get the boards out of the tank. It's not going to disolve your pliers, but it will deffinatly ruin the finish. (It's acid guys, c'mon!!). Dispose of waste etchant in accordance with your local hazmat procedures. When rinsing stuff off in the sink, use LOTS of water.

Thirdly: I assume no responsibility for anything bad that happens from the following of this procedure. So if you get absent minded and spill an entire tank of etchant on your dog, permanently stain him yellow, and the overflow eats through the floor of your house boat and it sinks, don't blame me.

Fourthly: I apologize for the size of the pictures. Most of them are rather large. I feel it's better to spend a little more time downloading the pictures and being able to see things in detail rather than to have quick downloads and fuzzy pictures.

Lastly: Think safety!! When using the etchant, wear gloves, wear eye protection, and ventilate! Most important, do it somewhere disposable. Don't do it on the coffee table in the middle of your living room, because the cat WILL knock over the tank. Then you have the rest of your life to try to explain to friends and neighbors what the big yellow stain on the carpet is.

‘Nuf said. Let’s get to it!

Step 2 : Get your things together

First let's get a few things together.
This is by no means a complete list nor are they the items you MUST use. Be creative. Whatever works...

Step 3 : The tank


This was supposed to be a picture of my tupperware etchant tank but the file names got messed up somehere. Just use your imagination........


As you can see here, my tank is just a Tupperware container with a good sealing lid. It's very important to have a good sealing lid. You can store etchant indefinably, but it's vapors are corrosive. Plus, you never know when you are going to knock the darned thing over. Sometimes I will etch in this tank, other times I will use another container that best fits the boards I am building at the time. (Tupperware is a wonderful thing!) In this HowTo I am etching 12 channel SSR boards. (see my other HowTo on SSR building) These boards are long and narrow so I'm using a spaghetti container (see picture in next step).

Step 4 : The tank accessories


As you can see in the previous step there are some other accessories involved. The etchant works best if it is heated and agitated. A board that would take 20 minutes to etch just sitting in a cold tank of acid, will etch in about 5 minutes is a warm, bubbling tank.

The heater:
The heater is just a common aquarium tank heater. They come in all shapes and sizes. The one I got was a short one for a small aquarium. A longer one wouldn't fit in the tank properly. I heat my etchant until it's about "almost too hot to wash your hands with" kind of warm. Remember, you want if very warm, not hot.

The agitation:
Agitation is accomplished using an aquarium air pump. You can't see it in the pictures, but glued to the bottom of the big tank is a small length of aquarium hose with holes drilled at 1" intervals. Connect this to a valve and you can regulate the ferocity of the bubbling.

Step 5 : More items needed


To make the traces on the copper clad board, I use a product called Press-N-Peel made by Techniks. You can see a HowTo on using it at http://www.techniks.com but I'll go over it again here. It's actually pretty simple:
You create your PCB diagram on your computer. You can use any drawing program, Windows' paint works OK but I prefer a product called WinBoard by IVEX (ivex.com). It takes a little getting used to but once you got it, you're there. They have a fully functional demo version (it's just limited to the number of holes you can plot) that you can download. Once you have your artwork done, you use a laser printer, or a copy machine, to print your design.
You have to remember to do your artwork backwards, as if you were looking thru the board. This is because when you iron the design onto the board, it will be reversed... i.e. correct for that side of the board.