Two sided PCB using toner method

This describes an easy method to make professional looking two-sided printed circuit boards at home.

Step 1 Get ready

This instructable assumes that you know how to generate a layout file using Eagle PCB or similar layout program. I use the toner transfer method of making PCB's (printed circuit boards) much like many others. The basic idea is to use a glossy paper, print the PCB design on the paper using a laser printer, and to use a hot iron to transfer the toner to the copper. I use the glossy paper that they have behind the counter at Kinko's. Go to Kinko's and ask for some sheets of their glossy laser paper, which is really cheap (about 5 cents a sheet). Some people advocate using glossy inkjet photo paper, but I think this is a waste and the cheap glossy laser paper comes off easier.

Anyway, once you have your design and paper, you will need to print the design. The key here is to mirror the top layer so that it will come out correct once transferred to the copper board. It can also help to include alignment marks (the T shaped things in the pic) beyond the edge of your PCB to help you align the two layers. See below.

Comments

[rayshobby]

Consider using a laminator instead of a hot iron. I've used hot iron before and it's a pain. As soon as I tried laminator, I never want to use a hot iron again. For example, a GBC pouch laminator from amazon works just fine.

[jmengel]

Good tip. Thanks.

[qwertyboy]

For cleaning, I just use some fine steel wool. It takes the toner off quickly, removes any tiny shorts, and shines everything up. After that, I usually wipe the board off with some acetone to get rid of any oils or other nasties and spray a light coat of clear onto the board. It keeps everything shiny and kind of acts as a flux.

[jmengel]

When you say clear, do you mean clear coat spray paint? It doesn't interfere with soldering at all? I've had some of the boards I've made get pretty corroded after being in use for a long time in my basement (high humidity). No failures but the corrosion is ugly. Thanks!

[qwertyboy]

Yes, clear coat spray paint. As far as I can tell, it doesn't interfere with soldering.

[clabrecque]

I did this and it worked great..I get digikey catalogs and the paper out of them works well.glossy and dissolves in water.HA now i have a use for all them stacked up! and this instruction is great..i never thought of binding the tow sides together first then sliding my bored in between..brilliant...Thanks

[jmengel]

Glad to hear it worked for you. Enjoy!

[teche]

its called pad2pad...... i think? Download it here http://www.pad2pad.com/download/index.htm
to do that click the download button :-)

[INELEC]

HI FRIENDS? COULD ANY ONE OF YOU TELL ME ABOUT SOFTWARE THAT MAY HELP ME CONVERT SINGLE SIDED PCB INTO DOUBLE SIDED ONE? THANK SO MUCH

[lee321987]

I just did my first board. I had my design printed by Fedex Office (formally "Kinko's") on their laser printer.
Acetone (Klean-Strip brand from Home Depot) removed all the toner with VERY minimal effort.

I can't comment much on the Fedex Office paper/printer/toner because I have nothing to compare it to.

[AJC894]

How did you get the alignment marks in Eagle CAD

[jmengel]

I just drew it in using the drawing tools (line, circle, poly, etc.) Make a copy of whatever you draw on the top and bottom layers and you are good to go.

[dan mihalciuc]

Hi
You know, I did a few of these PCB boards, one or two sided, and I was never happy when compared with the “professional” ones. The latest one I’ve tried to do (better) was using the “hot iron” technique. So, I had this glossy paper (I’ve even used those transparent plastic sheets made special for this purpose), I’ve printed my design on and, with a hot iron (as recommended) I pressed.
Well, if not hold enough, the ink will not melt and nothing will be achieved. If hold too long, then the ink melts but the strait, clean lines become smudged. And as each board is different in size and number of lines, it is almost impossible to extrapolate a “good” timing for all the other ones. And you cannot experiment with 20 for only one.
Any suggestion?
Thanks,
DAN

[jmengel]

Certainly these methods do not match professionally made boards. They are useful for one-off type quick and dirty boards though. If you need more than one, and want them to look good, I would suggest using the bare-bones service at www.4pcb.com. It is cheap and quick, and will get you a double sided PCB with tin plating, no silkscreen, no solder mask. Works great for me, both on the hotplate and hand soldered.

-Jon

[saone]

can this work if i use an injekt printer...NOT A LASER ONE?thanks...

[jmengel]

No. The laser toner is a solid that can be transferred as described. This is not possible with the ink printed from an inkjet.

[saone]

ok!thank you! by the way....great instructable!

[hintss]

you can have kinkos copy it onto the glossy paper, though.

[saone]

kinkos is a print shop or something?

[hintss]

pretty much

[MrSillyGuns]

ok im lost

[hondaman900]

I found the best way to clean off toner is to use non-acetone (acetate) nail polish remover. Wet a wad of paper towel the same size as your PCB with the acetate, and leave it to soak on the board for about 5 minutes. It should then wipe off easily with that piece of paper towel or another wetted with the acetate.

Bigger question for homemade double-sided boards is how to solder the pins under sockets and relays on the component side of the board without a bunch of extra vias to keep the component pad connections all to the bottom layer?

[cdvs]

This is my solution: http://DiyPcbVias.com

[jmengel]

The answer is more heat and more solder.  Or you can cheat the components up from the board enough to get an iron underneath.  I prefer the first method.

[Foxtrot70]

Excellent Instructable!  One word of caution.  I live in a rural area and have a Septic System for my house.  To protect the system ( in particular the the bacteria in the septic tank, the bacteria break down the toilet paper and solid matter or the #2 stuff) pour your chemicals into separate containers and take them to a Hazardous Waste Facility for disposal.  There is nothing more unpleasant than spending thousands for a Septic System repair or the smell.  Just thought you should know. 

[jmengel]

Good tip!

[shimniok]

Thanks for the fantastic instructable!!  I guess ironing correctly is the real trick... I have the hardest time figuring out when to stop ironing. Too much and the traces and pads smudge.  I can't seem to get the resolution you are getting... :(  I can do through hole, but until I get the ironing figured out SMT is a lost cause. :(  Any tips welcome.  Meanwhile, being able to do 2-sided would be awesome.

[jmengel]

Fine pitch SMT can be a challenge.  The key is to clean the board well, using a scotchbrite and some solvent or similar.  Getting good iron pressure without smearing is also important.  I find that using the smooth "magazine" type paper is critical for fine pitch SMT while regular printer paper is adequate for through-hole.  Even so, when scrubbing off the paper, you need to be careful not to scrub too hard.  Leaving some of the smooth paper residue behind is OK on the bigger features, and on the fine SMT pads and traces I will scrape between the pads with an X-acto knife to ensure that they will not short after the etch.  This can be a pain if you have a lot of high pin count SMT ICs, but if that is the case you should be using a commercial solution like "4PCB.com".  Their bare-bones 2-sided board service works great and is pretty cheap.

For toner two-sided, the key is to have the paper sheets larger than the PCB and to tape them together in alignment outside the edge of the PCB so that the iron doesn't have any bumps to go over or will melt the tape.  Holding the two sheets up to a window will allow you to align them, but don't expect super tight tolerances for your vias.  I'd say make your vias pretty big (at least 1mm) since you will have to drill them yourself and small via pads tear off the board pretty easily during drilling.  Also, be sure and DO NOT fill the vias in Eagle or similar since the drill bit will skitter off the copper via or pad when drilling if there isn't a center mark from the etch process.
Good luck.

[sarubin]

Great idea and good instructions. I have one suggestion with respect to improving the "alignment marks." For circuits that include small components, like ICs, it is very important to have exact alignment of the two sides of the circuit. I aided this alignment by punching small holes (pin holes actually made with a pin or needle) in some of the pads on the laser print. I made these holes around both the periphery of the circuit and particularly included a small number of holes inside the pads of the ICs (required very precise alignment because the pins were only 2 mm apart in my circuit). Then, when the two facing laser prints are held up to a window (or, in my case, I have a backlit illuminated table) the light shining through the pin holes of one side of the circuit really helps precisely align the circuit printed on the facing page.

[jmsaltzman]

Sound like a great way to line them up.  Old thread, I know, but I found it trying to figure out vias-- awesome advice re: fluxing the pads and lead!  Off to get flux in a few minutes and try...

I've had good 2-sided transfering results with this simple method:

• I put both sides of the board (one flipped) into a single pattern image, with a space between them for the thickness of the board, printing from Photoshop with "crop marks" turned on.
• I gently curl the paper over (with no creasing) to align the crop marks, then tape those edges together and press the paper together to get a soft fold.
• Then I insert a blank pcb strip at the fold, pressing it in to get a square crease to hold the edge of the final pcb.
• Folding it again at its end, perpendicular to the first fold, I end up with a nice corner pocket to drop my pcb blank into.

To laminate, I put the blank into the pocket and feed it through my laminator.  After one pass, I cut off the folded over side of the pocket (to keep the peper thickness even) and laminate another ten times or so.  I've been getting very nicely aligned layers.

[stuart57]

This has been an absolute education for me and i cannot wait to give this a bash. I do however need to know where I can purchase all of the needed equipment  mentioned, As I live in London,England the small village across the pond.  
            Hope you can help? Many thanks Stuart and Emma

[lsymms]

Question and a tip. question: I've tried acetone and it's a bear. Mostly because it evaporates so fast. Is brake cleaner easier to work with? additional tip: use avery label backs. After removing the labels, print on the glossy side of the backing. Iron as per instructable, and leave it to cool until it gets to room temp. The backing should come off leaving perfect toner traces with no residue. I've just thrown out the labels or hand written on them before using the backs but I think you should be able to print on the lables and use backs. Buy the full sheet or half sheet labels as the smaller sized ones put perferation lines in the backing.

[lsymms]

UPDATE 2: different toners react differently to acetone. My Samsung's toner comes off in one wipe with toner.

[JohnnyVegas]

Just pour a cap full or two of acetone on the board and let it sit about 10-20 seconds first. Then just wipe. All toner will be removed. If some residue still remains, do it again.

[lsymms]

Good suggestion! I'll try that next time I have problems.

[lsymms]

UPDATE: Avery changed their backing on their labels from the last time I used them. Now they have angled slices along the backing to aid in automated label affixers, which means this won't work at all (there goes $12). I'll be trying the kinkos paper on very small traces and will report back.

[jmengel]

The avery back thing sounds interesting I will have to give it a try. Brake cleaner also evaporates quickly, but it was the only hard core solvent I had handy that could remove the toner.

[raykholo]

so.. will it work with an inkjet printer though? nice idea and if it does i will definitely use it...

[jmengel]

It will not work with an inkjet, but will with a photocopy of an inkjet print. The key is the heat fused toner, which is why inkjet will not work. To sum up, if it uses a powdered heat fused toner then you can transfer it using the described method.

[GTechno13]

So does this laser photocopy need to be "fresh"? I don 't have a laser printer but getting a copy made somewhere will work at home later?