Tutorial Make your own Pcb with Toner Transfer

Hello,
as some wants to see, I show you my way to make a PCB. There are many different ways to make it.
In this tutorial I show the Toner Transfer Method. Etching fluid is sodium persulphate.

First a little warning. You are handling with substances that can hurt you. Never let any Sodium persulphate get onto your skin or Eye's!
There are other etching fluids avalible which doesn't require heating and give good etrching results on room temperature. But they are very dangerous. I prefere sodium persulfate.

I'm not responsable for any Damage you do to yourself and other things.
You must enshure you use the chemicals correctly and use safety equipment.

1. Software

At first you need some Software to create the layout of your Pcb. Most time I use Eagle or Kicad. They are both freeware. But eagle is limited to 100x100mm workspace in the free Version so I prefere Kicad.

Download Eagle: http://www.cadsoft.de/download-eagle/
Download Kicad: http://kicad-pcb.org/download/

Both programms are really complex and powerfull. I will not descripe how to make your layout here. There are many tutorials over google avalible.

Here yoo find good info to start with KiCad. But it's in German. http://timogruss.de/kicad-loesung-fuer-die-leiterplatten-entwicklung/

2. Hardware

You need some blank PCB, depending on your project double or single sided:


Sodium Persulphate:


Thermometer:


Gloves:

Aceton:



Etching container:
or

You can etch your pcb in a container like above. But I really recomment some kind of machine.
The etching bath must be always in movement so there is always new fluid on the surface of the pcb. This will get faster and better etching results.
http://www.voelkner.de/products/546...model=S27228&gclid=CLO06cGU-8cCFRSNGwodtDUM6Q
Since the prices are very high I builded one myself out of cheap aqarium stuff.
You need a aqarium pump to create the airbubbles and a heater ( I used 75W for 1 L fluid) It is heated up in 15 min.



A Laser printer (got best results with old hp1020. The result can be very different in case of toner used):


A laminator. I used olympia 2020. When you take off the cover and remove some small metall plate your pcb run trough without modification:

Some stand drilling machnine like a dremel is recommented to drill the 0,8-1mm holes into the pcb for trough the hole components. (sorry for the chaos on my workbench)



3. PCB Layout and transfer

In this tutorial we'll make a small loadcell amplifyer for quadbridges.
Here are some 3d pictures of the final PCB. And also the layers that we transfer to our PCB created with kicad.
The top layer with parts and names must be horizontal flipped to get it onto the pcb the right way.
I will only document Single layer PCB at the moment. Maybe I make double layer later but it's the same principe.




I mostly edit the parts and make the solder pads a bit bigger and the holes a bit wider. This really helps when drilling or soldering your board.


As I mostly by rest pieces of pcb in ebay the chopper surface isn't very clean. I clean it up with some sand paper or wool until the chopper surface is shiny. This also helps the toner to hold on the pcb. After this clean it very well with Aceton and don't touch the surface.


Next print out your design, cut it out and cut it to size. For smd top layer pcbs please remember to flip the design verticaly before printing.
I always use a bit of tape to fix the design to the pcb while laminating. Becareful that the tap is not ofer your circuit design, only on unprinted paper.



Let the laminator heat up to max and let the pcb run trough a couple of times. I do it 5-9 times depending on the size of the pcb. This one I let run trough 6 times. I rotate it sometimes so the rolls of the laminator hit the pcb at every spot.

Put your pcb under water for about 30 seconds. Now you can start carefully peel the paper up with your thup. When finished it should look like below. Take a closer look at the gnd connections when you make a gnd chopper fill. There is sometimes some little pieces of paper left.


Last step is to cover unused areas with an edding so your etching bath will last longer.
You can also use this to rework some little mistakes from toner transfer as it is etch resistand.


If something went wrong you can wash everything away with aceton and do the procedure again.

If everything went well you are ready for the next step.

4. Etching

At this step take care of your skin and eyes!

As the air pump of my etching machine died, I show you the manual way of doing it. Machine will be shown on next pcb.

First heat up your echtfluid. I do this with putting my sotrage container in a hot waterbath.
If it's heatet up, put your etch container in a hot water bath, put your pcb inside and fill it with sodium persulphate. A thermometer will be usfull to watch the temperature of the fluid.
Sodium persulphate needs really high temperatures max. 50°C in other ways it will take really long and maybe etching your toner away too.




Watch the procedure and use the thermometer to make som water circulation on top of the board.


After some minutes you can see the first chopper is gone.


After another few minutes it's complete and should look like this.


Your etching fluid will gets blue if it is used. You can reuse it until it gets deep blue.

Don't wash the etching fluid away in your washbasin.
Store it in a container and bring it somewhere where you can recycle
hazardous waste.

now wash the pcb under fresh water to remove some rests of the fluid.


You should end up with something like this.


I always leave the toner applyed. I remove it after drilling. So i have some kind of protection.


5. Silkscreen

It's pretty much the same as in Step 3. but this time you do it on the non chopper side. You neet do get your paper into position. I always make this at my window. The light shines trough the pcb and I can align the silkscreen. Fix it with a little tape, laminate, peel...




As it doesn't gone well you can wash it away with aceton and start again.
This time its not 100% but I will let it as it is.
You can now cover the silkscreen with some clearcoat if you want. I really recommend this, as the toner in top is very lose. I do it not in case of timing to get the tutorial finished. In the end you will see that some silcscreen is gone during work.

Here is the finished pcb cutted to size, ready for drilling.



6. Drill

Now we are ready to drill the holes for components or mounting. Be shure to do this from the bottom chopper side, as the top silkscreen can always be a little bit off.
I recommend a stand drill. A dremel one will be enough. Otherwise you will broke 1mm and 0.8mm drills very fast.


Now you can wash the toner at the bottom side away with aceton. I always sand the pcb again clean it with aceton and spray it with SK 10 for better soldering and chopper protection.



Now you are at the end and ready to solder your pcb.

After soldering you should be ending up with this.


It's not the nicest Pcb, but hopefully it's useful for someone here.

Good idea to document this process!

Indeed etching machine are costly: tell us more about your DIY etching machine, please!
80€ + 60€ shipping on Aliexpress

I will go into detail when making the next pcb i also add a video of the working machine. But it's nothing special

a 1 DOF etching machine:


a tutorial on converting an inkjet printer to print PCB
http://www.instructables.com/id/Converting-an-Inkjet-Printer-to-Print-PCBs/?ALLSTEPS

@tombo ... What kind of papers did you use for the toner transfer ?
I'm using the "Vinyl press and peel" papers .


Hot water path in the sink for etching improvement speed ... inverted floating boards for hot etchant circulation current beneath it .

Like I said i don't know the word in english. In german it is called "gestrichenes Papier" is't mostly for old plotters on big rolls. It got a glossy finish like Photopaper. The good thing on this paper is you make it wet with a little bit of water and can peel it easy off. Mostly some paper will stick on the tracks and gnd pads and helps the toner to resist against the etching fluid. So there is nearly no underetching of the toner.

With all other papers the tranfser wasn't ferpect, you can peel the tracks off the pcb or you waste one hour to peel all the paper off

I read much about this press and peel paper but onhloy find it at a very high price. Your results looking really good.

Next thing I maybe want to try is the solder mask laminat
http://www.octamex.de/shop/?page=sh...category_id=5848924494118370762daa6f026e22f7&

Move forward to 16min.

I updated the tutorial, and hope the process will be clear for you.
If not fell free to ask. I will always be happy for improvements.

Useful info. thank you