5pcb

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Introduction: 5pcb

A simple 5-step process to etch your own printed circuit boards at home.

You'll need the following ingredients:
  • laser printer/photocopier & transparencies (I go to a print shop to do this)
  • copper board (local electronics store)
  • scrubbing pads (SOS or a generic brand is perfect)
  • iron
  • rubber gloves (like the ones you use for washing dishes)
  • Ferric Chloride or Ammonium Persulphate (local electronics store)
  • drill and drill bits

Step 1: Design and Print

Design your PCB. I use anything from Adobe Illustrator to Cadsoft Eagle. Once you think everything is perfect, print it on a piece of paper and test it by placing your components over it. You have to 'flip horizontal' your final design so that the transfer from the transparency to the copper board 'restores' the intended design... Then print it on a transparency. It has to be a laser printer or a photocopier because we want toner on the transparency. If you can, ask the guy at the print shop to make it as dark as possible (more toner). I've noticed that I've had the best results at the worst print shops in town.

Step 2: Transfer the Toner

Now you want to transfer the toner (mostly made of molten plastic) onto the copper board. Set the iron to 'silk' (you'll have to experiement with the temperature...it took me quite a while to consistently get good results).

Clean and rinse the board with the scrubbing pads and soap. Dry it up. Place the transparency on the copper board, place a piece of paper on top if it all and start ironing! Depending on the size of your circuit, it takes about 2-3 minutes for the copper board to get hot enough so the toner sticks to it. When you think you're good, immerse the copper board (with the transparency stuck to it) in cold water. Then you should be able to peel off the transparency while the toner remains on the copper board.

If the toner did not transfer completely, you didn't iron long enough and/or didn't set the temperature high enough. If the toner transfered but is smudged on the copper board, the temperature was too high and/or you ironed for too long. You can use a Sharpie or any other permanent marker to fix parts of the circuit that did not transfer properly.

Step 3: Etch

You're almost done. Put the gloves on, pour some etchant in a plastic or glass container and immerse the board. At room temperature, it can take up to half an hour. Mixing the solution as it's etching can speed up the process. Another good way to dramatically decrease the etching time is to warm up the solution. Now I strongly discourage you to get creative with the microwave or your precious pots and pans. You can however dip the container in warm water poured from the tap. When it looks good, clean the board in running water.

Step 4: Clean

Use the scrubbing pads to remove the toner from the board.

You can reuse the etching solution, so just pour it back in the original container. Do not pour it down the drain! It will corrode your copper pipes... Over time, the etching process will take longer and longer. When the solution becomes unusable, contact the waste management organisation in your community to know where to dispose of the chemical.

Step 5: Drill

For those of you who do not use surface mount components, you'll need to drill holes in your board. I use a Dremel (you can find generic versions for less than 40$). You'll need tiny drill bits (#66-#60). Most places you'll go to will rip you off with those tiny precise bits (10-15$ each). However, some places like Lee Valley sells them for ~$0.50 each.

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    63 Comments

    1 part HCl + 2 parts H2O2 = "PCB Cocktail"!!!!

    I keep looking for the downside to it, but it doesn't stain the sink, doesn't turn your fingers brown... what's not to love?

    May smell a little funky when the acid is opened, but otherwise ferri-chloride can just go play with itself.

    3 replies

    Here do you usaly find HCL ?
    H2O2 its easy to find but HCL ...

    Take a look in the hardware store. It's used as a cement/driveway/pool tile cleaner.

    I have used a clear etchant before from Mega Electronics but I don't know what it consisted of. It did seem to etch a lot quicker and of course was cleaner... although I heard that it was very dangerous in comparison to FeCl3. Not sure if this is the same stuff that you talk of or not?

    What's the opinion on drill bits?  I've heard people say that if you don't use tungsten carbide, the bit will wear away from the fiberglass.  Is this true?

    2 replies

    I think this is true to some extent. The fiberglass in the board is very abrasive to the drill bits. I have some specific tungsten carbide drill bits specifically for drilling PCBs in mini sizes (admittedly they are about £2.50 a piece and very easy to break if not used in a drilling stand). These work wonders and have drilled many boards. I was drilling a grill for a speaker once though and I got through 3 drill bits! The holes were drilled using the PCB drill first and opened out using a 2.5mm standard HSS drill. Now of course these all need sharpening. Speaking of which I may go to the hardware store on my way home and get a selection of small tungsten carbide drills for such purpose now!

    no...not neccessarily true...i drilled 6 pcb's BY HAND with a dremel engraving bit...it was small enough for the job i was doing and still has bite in it to drill. and the crappy etchant from radio took 1h to etch away 80% of the copper i wanted gone.

    i suggest u use a glass bearker or other such container for holding the etching sloution

    2 replies

    if your working on a small project a small plastic bowl works just fine. i use one of my son's mini cereal bowls for etching w/ radio shak etchant...and no i dont was out the bowl and give it to him...its permanently mine now!! :)

    I was going to say! I seem to recall someone in my house using a plastic jug for antifreeze and permanently damaging it! Needless to say this is now replaced and only used in the garage!

    If i was making a single sided board (traces on bottom), would i have to mirror the image before printing, or could i leave it as it is?

    6 replies

    Yeah, you have to mirror the image if you are using the iron on method

    Thanks! Are you sure though, surfing around, some people say for toner transfer with eagle on the bottom layer you don't mirror,because you are actually lookin through the board, and that you only mirror the top. Oh well, i have no idea, I will mirror the board and see if the text comes out right, if it doesn'y, i will clean and leave it as is. Thanks!

    It depends on the program that you use to design it with. I use something called Circuit Wizard and they normally come out the wrong way up which is fine because they end up the correct way once ironed onto the copper board. There is an invert and also a mirror feature on the program though if required. The sure way of doing it is to put some text on it and if you need to hold it in a mirror to read it then it's the correct way for the toner transfer method. If you can already ready it then it's wrong.

    I think you do leave it as is. I'm sorry as I didn't understand your first question. I assumed you just wanted to make a single side board.

    So if I now understand your question; I dont think you need to mirror it. Sorry for any confusion.

    Thanks man, i thought you didn't need to mirror it. No, no you didn't confuse me, actually it just aided in the logical thought process. Thanks, i think ill go make that board now

    you dont have to mirror it, just remember where the components are supposed to go and ur good. but mirroring sure does make the process easier.

    this is a great guide to etching, thanks! Only a question, you use transparencies, but are not they made by plastic? I thought they should melt down under the iron...

    1 reply

    I'd have thought this but I have to admit I gave it a try and it does work... to some extent, I've seen videos of this and it works perfect, although I ended up using an indelible pen to fill in the patchy bits. The transparencies must have a really high melting point... because considering they work in a laser printer they don't come out molten ;)

    I like your name! It just haunts me because it seems so familiar but I just can't seem to put my finger on it!