Introduction: Vinyl Sticker PCB - How To

About: Lazy Old Geek

So this Lazy Old Geek (LOG) is getting in to making PCBs. I’ve already done one Instructable:
https://www.instructables.com/id/My-PCB-Making/
I still like to use Eagle CadSoft but my friend, OffTheRails2010 told me about a better toner transfer method using vinyl stickers. Well, I don’t know why they call it vinyl stickers but it works better than glossy paper. Much of this Instructable comes from this website:
http://en.electroni-city.com/
It’s probably just me but I found this hard to follow and used CAD software, I’m not familiar with.

Here’s an ebay source for the vinyl:
http://www.ebay.com/itm/380452333884?var=650054809089
There’s probably better ones and you should also be able to buy locally in sign shops.

Step 1: Laminator

So along with vinyl stickers, I also decided to use a laminator to make PCBs.
Now this is probably optional as you should still be able to use an iron. But for me, it’s a lot easier to use a laminator.
The one I bought is an Apache AL9.
http://www.amazon.com/Apache-AL9-Document-Photo-Laminator/dp/B0012UEU5S/ref=sr_1_4?s=office-products&ie=UTF8&qid=1364776625&sr=1-4&keywords=apache+laminator
 Mostly because it was the cheapest I could find.

I found three problems with this laminator:
Problem: This laminator will not take the more standard 0.062” thick copperclad.
(Copperclad is what they call the board with a thin layer of copper on it used to make PCBs.)
Solution: Well I happened to have some 0.031” and got it at a pretty good price.
http://www.ebay.com/itm/310599659225?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
For many people, this is not a good solution. I’ve read that some people have modified the rollers to take the thicker copperclad, but I don’t want to do this. Also, apparently, there are other laminators that will take the 0.062” copperclad.
Problem: This laminator will not get hot enough to toner transfer PCB traces.
Solution: This is pretty common for cheap laminators. Typically, there are two bimetallic thermal switches that control the temperature. See picture.
Procedure: Now mine were pop riveted in so I had to drill them out. Some people suggest sticking a piece of copperclad between the switches and the aluminum plate. This will probably work. But I decided to replace the switches.
Most of the ‘experts’ on the Internet suggest the ideal temperature for vinyl toner transfer is 170C. Mine were originally 110C and 135C. I think there is a good reason for two different values but I replaced both with 165C. I chose 165C instead of 170C mainly because I could get them cheaper.  
Apparently these are all labeled as KSD301s, so you can search on ebay for KSD301s and look for the temperature you want.
Warning: Many people said they had to replace the thermal fuse also to accommodate the higher temperatures. I didn’t have to. My fuse is rated at 192C.
Warning: This modification will run the laminator at hotter temperatures then it was designed for. I make no guarantees that this will work or how long it will last.

Problem: When toner transferring small pieces of copperclad, it is hard to feed and extract them through the laminator.
Solution: I decided to cut big slots in the feed and return side of the laminator top cover. See picture.
This makes it easier to work with small pieces of copperclad. It also allows the laminator to vent off some of the extra heat.

Step 2: Toner Transfer With Vinyl Sticker

I use the same process for creating schematic and board with Eagle Cadsoft:
https://www.instructables.com/id/My-PCB-Making/

Okay. Vinyl sticker is more expensive than glossy paper from magazines, so a different technique is used.

The board information needs to be transferred to the physical PCB. I use something called toner transfer on vinyl using a laser printer. An ink jet printer will not work for this process.

First, I create the images for printing.
The board view in Eagle Cadsoft contains a lot of information that you don’t want on the actual PCB. Here’s how you limit that information.
Bottom trace Layer
Eagle: In the board editor, there is a little icon called Display (Show/Hide Layers). It's in the upper left corner. Click on it, select <None> then click on (highlight) these layers:
            16-Bottom
            17-Pads
            18-Vias
            20-Dimensions

Now, just the bottom trace layer should be displayed similar to what you want to put on the copper. See first picture
Select <File><Export><Image>
            <Monochrome>
            2400 DPI.
            <Browse> Select the directory and file name, e.g, AudioTraces.png that you want. 
            Click <OK> to export as image. Using 2400 DPI, this will take a while and create a big file.
See first picture. By the way, this is a different PCB.

Note that the traces(copper) are in white. For toner transfer, they need to be in black. So you need to transform it. Now I have Adobe PhotoShop Elements. There are other programs that can do this. I know some people use the free GIMP program. But here’s how I do it.
Make Negative:
Open Image with PhotoShopElements
Select <Image><Crop> Crop <Check>    Limit to just the rectangular outline and the dimensions
<Select> All
<Filter><Adjustments><Invert> Now you will have black traces on white background, see picture.
<File><SaveAs>....
e.g., AudioTracesINV.png. Now you have the inverted image.

Step 3: Printing Traces

Pre-setup laser printer: (This process will not work with an ink jet printer.) The idea is that you want it as black as possible and no scaling.  The setup I used for my Laser printer:

Samsung ML-1865W Setup
Basic: Quality: Best
Paper: Scaling Options: 100%
Graphics: Darken Text, All Text Black
            Fine Edge
            Toner Saver: Off
            Darkness: Dark

This next step is a little tricky. I will summarize the process then provide some details.
First: We will print a copy of the traces on the laser printer on plain paper. This is to locate where on the paper, the traces will print out.
Second: We will put a piece of vinyl over the traces on the paper.
Third: We will run the paper with vinyl through the printer again.
Hopefully, the trace image will be printed onto the vinyl.

First: We will print a copy of the traces on the laser printer on plain paper.
Since we will print this piece of paper twice, we need to be able to replace the paper in the paper feed tray in the same orientation. So find you printer paper feed tray and mark the top sheet with a pen or pencil. I marked mine ‘Bot Right’ in the corner.
Most important is that it prints out the correct size. I print directly from PhotoShop Elements, making sure it is set for ‘Actual Size’. (and for the laser printer!!) You can also use MS Office Picture Manager but don't forget to unclick "Fit to Page".
After printing it’s a good idea to measure the outline to make sure it’s the correct size. Use the dimensions and measure the paper print out.  And look for any other problems. See picture.
Second: We will put a piece of vinyl over the traces on the paper.
Now, using the dimensions of the traces, cut a piece of vinyl a little larger than the dimensions. (You want it bigger as your second print may not be in the exact same spot as the first.)
Remove plastic covering from the vinyl and stick it over the traces on the paper. Do this carefully so you don’t get any bubbles or creases.
Third: We will run the paper with vinyl through the printer again.
Wipe the vinyl off with some tissue paper.
Stick the paper with vinyl back into the paper feed tray, in the same orientation as it was originally. Now print the traces again.
Hopefully, the trace image will be printed onto the vinyl.
The next picture is actually the silk screen printed on the vinyl but the traces should be similar.

Step 4: Toner Transfer to Copperclad

*********************************WARNING***************************
Acetone is pretty nasty stuff. You should always use gloves
And work in a well ventilated area.
*********************************WARNING***************************
Cut a piece of copperclad to the dimensions of the PCB.
Clean it. I use Scotch-Brite and using gloves, acetone.
Cut the paper/vinyl to the dimensions plus an extra ¼” (or so) border around the traces.
Place the paper/vinyl on a flat surface.
Without touching the copper, place the piece of copperclad (copper side down over the traces aligned with the outline.
Tape the copperclad to the paper/vinyl. I use regular transparent tape. Some people use special tape.
Trim it especially if you have sticky tape sticking out.

Warm up the laminator.
Run the copperclad/paper/vinyl through the laminator several times.
How many, you may ask? Well, I don’t know. I usually run mine about 10-12 times. This is the actual toner transfer step. There are several variables, that can affect this: board size, speed of rollers, temperature. It takes a couple of passes to warm the copperclad up. It is probably better to do more than less. It shouldn’t matter whether it’s pcb up or paper up. And it shouldn’t matter where on the laminator. I like to move it a round so maybe the rollers will wear more evenly?
If you can see the traces showing through as in the picture, then it’s probably ready.

Dunk it in cold water. I don’t know if this is necessary but it does cool it off.
Cut along the edges of the PCB with an Xacto or sharp knife.
The vinyl should peel away from the copper.
Using an Xacto, peel off the transparent tape.
  There will probably be some sticky residue but ignore for now. We’ll get it later.

Examine the copper. It should have some solid black toner where the traces will be. Sorry, I didn’t get a picture of this.
If there are major problems, clean off with acetone and start over with printing.
If there are minor gaps, use a red Sharpie to fill it in. Let it dry and repeat a couple of times.

Step 5: PCB Etching

Etching is the process of removing the copper from where you don’t want it. The principle for toner transfer is that the laser toner outlines the traces you want. The etchant will remove copper where there are no traces.

I use the follow etchant per this Instructable:
https://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/

*********************************WARNING***************************
The muriatic acid is hazardous. Do not breathe the fumes
Do this outdoors or in a well ventilated area
Use plastic bottles, containers and utensils. NO METAL!
Always Add Acid (AAA)
   Put the hydrogen peroxide in first
   Then add the muriatic acid
*********************************WARNING***************************
Two parts hydrogen peroxide (3%)
One part Muriatic acid (31%)

Etching:
Place etchant in a plastic container large enough to hold the PCB.
Place PCB in etchant container.
I guess it helps to stir up solution but don’t breathe.
Wait until copper is etched away. This may take 30 minutes.

NOTE: The Instructable says you can use this etchant over and over. I haven’t had any luck doing that. Do not throw old etchant away or flush it. Do recycle as hazardous waste.

I drain the etch solution and PCB into a recycle bottle, then carefully flush it under running water.
Use a paper towel and acetone to remove the toner and sticky residue from the tape.

See picture. 

Step 6: Silk Screen

A silk screen is all the printing, information and component outlines shown on the top of the PCB. This is useful for stuffing components and later for troubleshooting. Probably you will do parts of this procedure in conjunction with the traces but I made it a separate step.

So we have to create an image for the silk screen.
Eagle: In the board editor, there is a little icon called Display (Show/Hide Layers). Click on it, select <None> then click on (highlight) these layers:
          17-Pads
          18-Vias
          20-Dimensions
          21-tPlace
          25-tNames
          27-tValues

Now, just the silk screen and pads should be displayed.
Select <File><Export><Image>
          <Monochrome>
          2400DPI.
          <Browse> Select the directory and file name that you want.
          Click <OK> to export as image.

Again you will notice that the stuff you want printed is in white and needs to be black so again we need to Invert. So what isn’t so obvious is that since the silk screen goes on the opposite side of the traces we need to flip the image. Here’s my procedure.

Make Invert and Flip:
Open Image with PhotoShopElements
<Image><Crop> Crop <Check>   Crop the image to contain the outline and dimensions
<Select> All
<Filter><Adjustments><Invert>

<Image><Rotate><Flip Horizontal>
<File><SaveAs>....

See picture. Note that the printing is mirrored.

Use the same procedure as with traces.
Mark the blank printer sheet.
Print the silk screen.
Cut the vinyl.
Attach it to the printed page.
Stick the paper/vinyl in paper feed.
Reprint.
See picture.

Cut the paper/vinyl leaving about ¼” border around the silk outline.

Aligning the silk screen with the traces:
I know when I cut copperclad and tape it to traces it is far from perfect. This makes it a little harder to aligning the silk screen with the traces.
So what I do is take the etched PCB, find a couple of pads on opposite sides of the PCB and drill them out.
I find the same holes on the paper/vinyl and drill them out or open them with an Xacto.
Next I take a couple of cut off resistor leads, insert them into the two holes and insert them into the matching holes in the silk screen. See picture.
Now the silk screen should be properly aligned with the PCB.
Scotch tape the PCB to the silk screen.
Remove the resistor leads and trim the paper/vinyl.

Warm up the laminator and follow the same procedure as with traces.
Be careful, the copper side gets hot. Use gloves if you want.
The silk screen came out pretty good. The backside of copperclad is not the best surface to be printing on. I’m not sure how to keep the silk screen from wearing off. I imagine there’s some good spray on clear sealant?
See picture.

TIP: I’ve been doing another thing, I didn’t mention. In Photoshop Elements, I open a blank file and copy the traces and the silk to it. Depending on the size, you can have multiple copies of each. With this file you can print the traces and the silk at the same time and even make multiple copies if you’re planning to make more than one PCB.

Conclusion: I like this method of making PCBs with my laminator and vinyl stickers. They seem to be more consistent and it apparently will do much smaller traces then my old glossy paper & iron method.