(Mostly) easy PCB manufacture

This is an easy way to create your own PCBs at home. The method is based on the "5 Bears" process (which is itself based on Tom Gootee's process). I've added a couple of refinements.

Step 1: Create your design

Start out by laying out the PCB traces & pads with your favorite CAD or PCB design program. I used Pad2Pad, mainly because I found that program pretty easy to use, and it's free for download. You're supposed to use Pad2Pad to design a board, then send the file to the company for manufacture. Instead, I use this design to create my own etching mask.

Unfortunately, you can't export p2p files into other formats. So, I printed the board layout to a PDF, then opened the PDF into Illustrator, which allowed me to clean up & fine-tune the design and separate it into layers. This technique is for creating single-sided PCBs, so I made two masks: One for the copper traces & pads, the other for the silkscreen. You need to print out a mirror image of your masks -- you'll see why soon -- but because the traces go on the back of the board, you can print those out normally. The silkscreen mask should be printed out in reverse.

I use 2pt lines for most of the traces; that comes out to about 0.028".

Comments

[GenesisMaster]

Your technique seems excellent, but is there no risk of damaging the PCB if the silk screen and the traces must be on the same side of it?

[yaly]

Hi you drilled after applying the etcher my dad is a professor in physics and told me that the etcher's little particles some of them penetrate the toner and make the copper under it fragile so he tells me to drill before etching try it and tell me please reply soon.

[dviraj00]

hey,guies i have a confusion that how many PCBs i want to build this plz help me in this...............

[Mr. Stealth]

Where do you get the board? What kind is it? An in-depth explanation would be nice.

[guerroloco]

It's an ordinary single-sided copper PCB "blank" from Radio Shack. You could get it from any of the usual online electronics parts places, for example http://www.allelectronics.com/make-a-store/item/PCB-46/4-X-6-SINGLE-SIDED-PC-BOARD/-/1.html

[Mr. Stealth]

Ok. Thank you. I want to build the Ironman Arc Reactor by Honus and I need to know how to make my own PCB. You did a very good job at explaining this. Well done.

[i.c.rhodes]

How would you go about converting a schematic to a pcb layout manually, with no software. I would like to teach students how to do this before they go on to using layout software.

[raykholo]

what guerroloco says is very good advice personally i use pad2pad because of its simplicity of use to hand draw a pc layout, try positioning connected components next to each other to save time and hassle to make "extensive" traces also color in a ground plane to save on etchant hope this helps

[guerroloco]

If it's a simple circuit, I re-draw the schematic several times until I have a version that has no crossings. If it's more complicated, i'll use a schematic layout software (like ExpressSCH, http://www.expresspcb.com/ExpressPCBHtm/Free_schematic_software.htm) that lets me move connected components around. It might require running connections between terminals (or "through" or underneath components -- see U1-U8 in my picture to see what i mean). The goal here is not compactness or even relative position of components, it's just good topology with fewest crossings (which would require jumpers). I also try to move similar off-board terminals close to each other (for example, power supply + and -). Once I have a design with the least number of crossings, I'll use a PCB layout program, add all the components, arrange them more-or-less like my improved schematic, and connect them. At that point I can move them closer together, rotate, shorten/simplify trace routing, etc.

[Inovative Invintor Joe]

OK what was the chemical you used to etch the copper?

[guerroloco]

It's ferric chloride, commonly available at Radio Shack or any of the online electronics stores. It's kind of nasty stuff. This guy has an instructable that suggests a more benign solution (haha): http://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/

[raykholo]

yeah its reusable u gotta get rid of ferric chloride after using it and its "toxic" so theres this whole big deal about it, involving going to hazardous waste facilities. this stuff should be better...

[bman22]

I just wanted to let people know, there are much better ways to do the toner transfer than photo paper. It has failed pretty much every time for me. After reading the comments I tried numerous things. I tried taping wax paper to plain paper (it works OK if your laser printer doesn't melt it to a crisp), magazine paper (its a little tricky to keep the printer from jamming), and the best thing I have found is the waxy side of avery labels. I didn't even need water, it just peeled right off leaving the toner perfectly in tact. If you use a lot of them around the house (we do) stop throwing away the backing, because they are perfect. no melting, no jamming, and easier than photo paper. Also, does anybody know where a good Instructable on the actual etching method is? I know this toner transfer method fine, but I have never etched a board, because I could never get the transfer to work. all of them just say etch it in ferric chloride. I have that, and a container, but I need a good Instructable on exactly what to do.

[jamilm9]

would this paper work
http://www.staples.ca/ENG/Catalog/cat_sku.asp?CatIds=&webid=613982&affixedcode=WW

[Seifpic]

I'm not sure why, but this is the best 'make your own PCB' Instructable.

[vdr20]

I used hp glossy paper. When I iron the paper onto the board half of the toner stays onto the board no matter how long I iron it on fior. What do I do?

[collard41]

I feel sorry for all of you out there that have to use this method, hard and laborous (did i spell that right!). i go to school and what we do is print out the design on a special type of tracing paper (high quality) and then put it in a UV exposure box with the board, (the board has photo resist on it). and then just dunk it in an etching tank, i cant remeber what chemical we use, it isnt ferric chloride. it takes about 10 mins and then you take it out of there and put it in the special rinsing tank. i dont bother to put a silk screen on because i can just refer to the schematic and layout. i dont use eagle i use Proteus. it costs about £1500, but the school paid for it. it is much better and easier to use. but then it is what professional companies use.

[buiocchi]

what is the importance of dipping it into the etching liquid?

[CyberBill]

Etchant essentially eats the copper off of the PCB. The point of doing the toner transfer is so that certain areas of the copper-clad PCB are covered up by toner (a permanent marker does the same thing), and thus protects the copper from being eaten by the etchant. Afterwards, you just use the fingernail polish remover (acetone) to clean the toner/marker off of the board, which reveals the still in-tact copper below it.

[sha4096]

I have tried with two Laser printers. The first one, the HP LaserJet P1005 has a great toner and will easily transfer in less than a minute of ironing using paper from magazines. However, the toner tends to melt and you must not press too much when ironing otherwise you will loose details. The second printer, the Brother HL-2000 has a toner which is more thermal-resistant. It is also more prone to paper-jamming. So set the printer settings such that the highest paper thickness is activated. Ironing is more difficult with the Brother toner, I found that the best way for small PCB was to leave the iron on top of the paper and leave for 5 minutes without moving the iron. Heat is the way to go if you want to transfer with Brother toner.

[nickjohnson]

Very tricky. I tried this with a used iron bought from the salvy. Even at the highest setting, it's probably not as hot as it should be... First time, I tried no more than 3 minutes, and very little transfered at all. Next, I tried a total of 7 minutes and most of the design was trasnferred, which I touched up later

[carpus101]

Hi nick, nice I found yr words here. You see I am trying to find PCB with Iron layer and not copper. You know how and where to find it?? Appreciate yr advice - roger

[nickjohnson]

Is there any good way to agitate or heat the etching solution? I was thinking of using a glass container with a halogen lamp against it, or to put the whole thing on a turntable.

[Dodgy]

Constant agitation is virtually essential. You can use a brush or a stick to move the board around or to move the etchant over the surface(s) of the board so as to always have some fresh etchant on the copper, and therefore homogenise the dissolved copper.

If the etchant is hotter, it will work better (ferric chloride). But don't make it over about 80deg C, or the fumes could start eating into the copper wiring in your ceiling light (probably not). Or your health may suffer from breathing it in.

Ammonium persulphate apparently needs to be in a window zone of temperature.

As for the hydrochloric acid and hydrogen peroxide method.... Apparently it can become an exothermic reaction and provide heat to itself, eventually exploding... So I wouldn't overheat that, if possible!

[sumit381]

Where can I buy this copper board? Is it available at hardware stores like Home Depot, Lowes, etc? And how much do these boards range price-wise? Is there any specific name for this board that I should ask for when I go to the store? Thank you for your help.

[Dodgy]

It's called copper clad fibreglass sheet, or blank PCB or FR-4 with Cu coating, or other names you may choose to make up. There is also a phenolic or SRBP type, which is older and sometimes still used today. There is also the type that they use in China for cheaply made TVs & VCRs, and most consumer items not needing a flame retardant ability. Their holes and egdes are punched, and the boards are often very flexible, and not reliable if flexed, but hey, they cost them a lot less than the high quality fibreglass PCBs (UL: 94-V0 or FR-4)
You won't find them at hardware stores, but electronics shops.

Price, about Aust./US$5 for a small board to $80 for a very large double sided, these are rough prices.
This will give u an idea of what's around. Farnell has locations all around the world.
http://au.farnell.com/jsp/search/browse.jsp?N=500001+1001200&Ntk=gensearch_001&Ntt=pcb&Ntx=

[guerroloco]

any radio shack will have these, or you can order online from digikey, all electronics, and hundreds of other vendors.

http://www.radioshack.com/product/index.jsp?productId=2102495

http://www.allelectronics.com/cgi-bin/item/PCB-46/search/4%22#34;_X_6%22#34;_SINGLE-SIDED_PC_BOARD_.html

[sumit381]

Thank you for your reply.

[OptimusTronic]

Gut Danke, this tutorial very good. Danke!! Saludos desde Guatemala!

[Swartzkip]

Im new to al this, but as far as i understand the only thing holding of the eching solution back is the toner from the printer. So you should use a paper that leaves al the toner on the bord. (correct?) A other instructable uses "baking paper" (stuf you use in the oven so that baked goods dont stick to the plate) to transfer designs on tshirts. Maybe that wil work too.

[Fritzk9]

On Step 6, you can save a lot of wasted time soaking off the paper backing by printing your PCB pattern on Toner Transfer Film (TTS) instead of paper. TTS film is a thermoplastic film that has a water soluble backing which releases it in about 30 seconds when dipped in water. See details at www.pulsarprofx.com under Direct Etch. You can purchase TTS film from Digi-Key (www.digikey.com) for $14.95 for a 10-sheet pack (Digi-Key stock # 182-1003-ND). Once you've used TTS film, you'll never go back to paper.

[LordSTITH]

I printed to the backing sheet of some Avery's labels. Worked great, the paper popped right off when I tossed it in a little cold water. It worked almost too well to believe. I want to see how wax paper works, though, because getting labels purely for PCB making is a tad expensive. I'd like to take my boards to the next level, though. I have a silk screening frame and I want to play with doing a silk-screened documentation layer, but before that I'd like to coat the board in whatever that green insulation is. Anyone know anything about the stuff?

[mrpiggss]

i just tried something and wanted to pass it along. i used HP glossy photo paper and copied onto it with an ordinary toner copier, ironed it on and it popped off leaving the toner behind. i did soak it for a few minutes in cold water. it's the HP photo paper with the real photo backing. it's thick stuff and it works like magic. no real soaking or peeling off layers of paper. i bought the paper at miejer. just thought i'd pass this along. i have 6 good boards in a row of the first try!

[i.c.rhodes]

How would you go about converting a schematic to a pcb layout manually, with no software. I would like to teach students how to do this before they go on to using layout software.

[sumit381]

Is there any precaution I need to take when I dispose of the etch solution? For example; would be ok to dump the solution down the drain or not? And if not, how should I dispose of it once I'm done? Thanks.

[guerroloco]

Do NOT dump ferric chloride etch down the drain!!!

You can dispose of it at your local hazardous waste disposal company (in my town, we have municipal hazardous waste drop-off dates).

Or, you can add sodium carbonate (washing soda) or sodium hydroxide (AKA lye or Drain-o) to neutralize it, until the pH value goes up to between 7.0 and 8.0. Test it with litmus paper. Copper will be deposited as a sludge. Allow the sludge to settle, pour off the liquid, further dilute it with water and then it can be poured down the drain. Collect the sludge in plastic bags and dispose of it as required by your local waste authority.

[Eriswerks]

I recently tried toner transfer PCB making for the first time, and here's what I found out. First, the type of paper you use really matters. Staples "photo basic paper" was the only thing that worked well for me. Second, the more ironing the better. I didn't iron one edge of my board well enough, and ended up with some bad traces. (I fixed them with a Sharpie.) Next time I want to place something flatter and harder than my ironing board underneath the PCB so I can press the thing down properly. Third, I used 1 part muriatic acid and 3 parts hydrogen peroxide as my etchant with good results. The muriatic acid is dirt cheap at pool supply stores and hardware stores. And finally, the toner was fiendishly difficult to get off after etching, even with acetone. I had to use some fine sandpaper on it to finish the job.

[guerroloco]

yah, I iron my boards on a good hard chunk of wood (piece of a 1x6) with a piece of scrap denim laid over the wood for just a little "give". I never had any problem removing leftover toner with acetone. Maybe you're ironing too hard :)

[x_pyro]

Hey where did you get your eching stuff from? i cant seem to find any.

[guerroloco]

I picked some up at the local Radio Shack, but you can get it online lots of places as well. It's sold in powder form. Look for anhydrous ferric chloride. for example here