Recently one of my focuses has been to find a way to make the PCB (Printed Circuit Board) creation process easier. I like being able to design something based on what I want in a circuit and just making it myself on the random weekend. While the toner transfer method has been my go to in the past it’s just not nearly as consistent as I would like it to be. The specific pressure of the iron and timing both make it a hit or miss approach. I’m not a fan of hit or miss I like to know something is going to work every time I try to do it. This sentiment got me exploring new ideas for PCB creation which is the topic of this project.
About a year and a half ago I found this webpage on modifying an Epson inkjet printer into a printer capable of printing on thicker materials such as copper clad board used by hobbyists such as myself to create custom circuit boards. As you'll notice that webpage is centered around an Epson C84 printer, but Epson printers are all somewhat similar so I decided to try this method on the C86 I had lying around the house.
Since I've been working on my own website (www.ryanpourcillie.com) I've documented everything about the project and thought it would be good to put it multiple places so hopefully numerous people can see it and try something new for themselves. I really tried to go into detail on everything I did in this process and the problems I had to troubleshoot because from looking around online there have been a few people who have done these modifications before, but no one really seems to have given a very good in-depth step by step build guide. Hopefully this Instructable can serve as just that.
So all that being said let's start with the tools and materials you'll need for this project:
- Obviously you'll need some form of an Epson inkjet printer probably of the C80 family as those are the ones I have seen modifications to in the past.
- A sheet of aluminum or steel or some metal sheet (about 9 inches by 14.5 inches roughly)
- Approximately 4 feet of 1/4 inch bent (90 degree corner piece) aluminum rail
- Some type of brackets and screws to secure them with (I used 3, you'll see an image of them later on)
- Some 4 - 40 screws (I used 1/2 inch long ones)
- Nuts for said screws (I used about 16)
- A small piece of scrap plywood and some other random scraps of 2x4 or something of the sort
- Epoxy and/or hot glue
- The drivers for whichever printer and operating system you decide to use
- An ink kit from Inksupply.com (more details on this later)
- A Dremel tool with grinding wheels to cut through metal
- Various screwdrivers
- Pliers or a socket wrench that fits the nuts or screws you'll be using
- A drill of some sort to attach the brackets
- A hot glue gun
- A heat gun
Once you've gathered all of those things you're ready to begin.
Step 1: Panel Removal and Breakdown
Once you get all that done you'll end up with the internals of the printer ready for modification.
Step 2: More Removal of Parts
Next up is the pressure wheels in the center of the printer. You don't really need all three sets and the center set could cause clearance issues when you send a circuit board through the printer. So to avoid this problem I simply removed the roller leaving a clear area for the circuit board to pass through.
Finally you'll want to remove the print head cleaning station. You'll want to be careful here! This station simply pops out from the press fit connectors it's sitting on, but it will have a tubing system connected to it. This tubing is necessary so make sure not to break it or remove it. Once you have those three things removed we can start looking at the heart of modifying this printer, the lifting process.
Step 3: Removing the Print Head Assembly
So on to the modification...
Let's start with the easy areas first and work from there. Starting with the front rail of the printer you will see two screws which you will want to remove. Once you do this the rail lifts away and you can set it aside for later re-installation.
Next you can focus on the two screws near the print head cleaning mechanism. By removing these two screws the right side of the printing assembly will be lose and removable. However you cannot remove this entire piece yet as the left side is one large metal piece and there is a small hidden tab which also holds the assembly in place.
This is where the Dremel tool enters the picture. You first want to look at the metal areas and plan out exactly where you would like to cut. I tried to minimize the area I had to cut because as I mentioned the sparks flying in your face is something you want to experience as little as possible. That being said you'll want to cut through the small interior tab to release the right side of the assembly before finally cutting around the entire left metal corner so that you can lift the print head assembly and remove it completely from the printer's base.
If you've been careful and follow the directions thus far you should have three pieces laid out in front of you. Check the images I've posted to make sure you have everything disassembled properly.
Step 4: Cleaning the Print Head (Optional)
Like I said this step is optional, but it really helped my print head work like new again.
Step 5: Reinstalling the Print Head Assembly Part One
Now that I've decided on the amount I want to lift the printing assembly I can begin inserting spacers to get the desired height. The easiest place to start is with the front rail system. As it is attached with two screws I simply bought some longer 4 - 40 screws and used two of the nuts that came with them as spacers. Once that rail is screwed back in it's done with and you can move on to the more complicated print head assembly portion.
Step 6: Reinstalling the Print Head Assembly Part Two
Once I had the brackets made I needed to mark where I wanted to drill for the bolts to hold these brackets in place. This process was simple for the bottom section. I just decided where I wanted to put the supports and then marked for the holes and drilled. Once I had those holes drilled I attached the bottom portion of the brackets so that I could line up the print head assembly and mark where the top holes should be drilled.
To make sure the top holes where in the right spots I went ahead and inserted the 2 spacer bolts on the right hand side where the two screws attach to the printer base. Once those where attached I aligned the brackets with the cut corner and use a level to make sure the assembly was in the correct position before marking the hole locations. At that point I removed the assembly again to drill those holes and then reattached the entire piece this time using screws and the brackets I had create to secure the entire assembly in place.
Step 7: Lifting the Print Head Cleaning Station
To make sure the cleaning station was raised the right amount I used a somewhat indirect method of measuring. You can obviously choose your own way to lift this, but what I did was reinstall it in the normal position before using two of the leftover brackets that I had to mark where the screw holes fell on the printer base and the cleaning station itself. From there I measured 3/8's of an inch down from the marks on the cleaning station and drilled pilot holes at those marks and the marks on the printer body. Once I had those holes I lined up the brackets to the printer body and attached them with screws before lining up the cleaning station and screwing it to the brackets as well.
When I turn the printer on and run cleaning cycles the cleaning station is lined up where it needs to be and works as it should.
Step 8: The Feed System
Again you can devise your own system, but here's what I've done with my printer. My first consideration was where I wanted to attach the feed sensor. This sensor is absolutely necessary or the printer will not function. What it does is it senses when material passes through its gap and relays that message to the printer so it knows exactly where the printing material is. The seond important thing to know about this sensor is that it expects a delay between the time that the rollers of the printer start feeding paper in and when the sensor is triggered. I'll go into detail about that more later though when I talk about the carrier piece. Since the sensor needed to be mounted in a place where the carrier would pass through it and I was already planning on making a plywood deck area to level the back of the printer body I decided it would be best to hot glue the sensor right into that decking near the edge of where the carrier piece would travel.
As you can see in the images I basically used a few layers of scrap plywood to create a level area in the rear of the printer. This decking area covers the large felt waste ink reservoir you'll see and also the metal power supply area. Basically all I did for this area was to measure out those two enclosed areas and cut layers of plywood until they were level. As you can see in the images again that took two additional layer in the waste ink reservoir and then I was able to lay one larger piece over the entire surface. Once I created this decking I cut a corner off of the top layer and lined up the feed sensor with where the carrier material would travel. This ensures that the material can travel through the sensor and set it off as the printer expects it to.
The main point of the decking area however was to create something to which I could attach support rails to. Using these rails I can simply lay the carrier and copper clad in the tray and let the printer take over. What I did for that was to take some aluminum that was bent into a 90 degree corner and cut it to the length of my expected carrier piece. From there I epoxied the rails to the decking and a third piece across the back for extra support.
With the feed system taken care of I wanted to test and make sure everything was functioning properly. To do that I finally cut my carrier material. I had a sheet of anodized aluminum lying around so I decided it would make a good carrier. To start I measured the width of the print gap which in my case was around 9 inches. With this in mind I decided to aim for something similar to paper size and drew out a 9 inch by 11.5 inch rectangle. Luckily however I read more information about the feed sensor before I cut that sheet because as it turns out that carrier would not have worked very well. From what I've learned the carrier piece needs to have a notch cut out of it that is about 3.5 inches long to allow for the proper delay between the feed rollers activating and the sensor triggering. So with this new information I modified my carrier outline to be a 9 inch by 14.5 inch rectangle with a 3.5 inch section cut out of one corner.
After cutting this carrier I installed the printer drivers on my computer and taped a piece of paper onto the carrier before running a print cycle to check for complete functionality. Everything came out and the printer functioned normally so I began to look forward towards the printing of PCBs.
Step 9: Filling the Ink Cartridge
If you follow that link above it will take you to inksupply.com which is where I bought everything I used for the ink replacement. All you really need if you have an empty cartridge is the Mis Pro yellow, but I bought a few things to make the process easier. The first thing I bought was an empty ink cartridge that they sell which will make filling the printer easier and I won't have to clean out an old cartridge. Secondly I bought a fill kit from them that supplies you with two syringes and a set of tips to fill the ink cartridge with. Finally I bought a device from them that resets the small chip that's on Epson print cartridges so that you can convince your printer there is still ink in the cartridges after they run dry and you refill them.
So using these things and my yellow ink I filled up the cartridge and got it prepared for installation in my modified printer so that I could run a final test and etch a circuit board to see the results of my work.
Step 10: Printing Test
Also for those of you who are curious about how detailed this thing can get I've also printed drj113's Ethernet Arduino board . This thing is packed full of little details and a few surface mount parts so that will give you a very good idea of what you can print with this system.
You can see how I'm going about printing in the video below and also see the two printed boards in the images.
Make sure to check out the next page for some important etching information before you proceed any further or you may ruin your boards!
Step 11: Notes on Etching
First, everyone should know is that if you go this route you need to use ferric chloride to etch the boards. I know it's nasty for the environment and a lot of people are trying not to use it, but the Mis Pro yellow ink will only work with ferric chloride as far as I know. You may ask how I figured this out and some of the images will show you how. I tried to etch my first set of boards in a mixture of hydrochloric acid and hydrogen peroxide, but the etching solution ate right through the Mis Pro ink and I ended up with those nice green boards of junk (oxidized copper) when I got frustrated and washed them off with water. Ferric chloride however does not eat away the Mis Pro ink and the etching will work as expected provided you follow the next suggestion.
Second, the thickness of the copper layer on your copper clad board is somewhat important. In the past I've used the old permanent marker drawing method and the toner transfer method of PCB etching on some copper clad that had a 2 ounce per square foot copper layer. This worked fine in the past as the permanent marker ink and the toner are a bit more robust and can withstand a longer etching process. The Mis Pro yellow ink however in my experience cannot withstand that same duration. This makes sense seeing as it wasn't necessarily designed for this purpose. The solution however is quite easy. If you choose a copper clad board with a thinner copper layer of 1 ounce per square foot the Mis Pro ink will survive the shorter etching process and give you a better PCB in the end. (If you're looking to buy PCB material check out eBay as it's a great source for bulk material at a good price. I buy from an eBay store run by the user abcfab and have gotten some good deals on some nice PCB material. The nice thing too is that you can contact him if you want a specific material (size, copper thickness, # of boards, etc.) and he'll work with you to get an order going.)
Lastly, my "Trace and Pad Test Board" was poorly designed. Yes that's a shot at myself, but I thought it was worth admitting. I realized during the etching process that there is way too much copper on that board that needs to be etched away. As such I thought about redesigning it with less open space, but then decided to stop trying to etch a nonuseable test board because I didn't want to waste more ferric chloride when I knew the process was working already. Also the Ethernet Arduino serves as much a better measure of printing and etching with this new printer modification as it will be a functional board that I can solder parts to and test traces on.
I know that those may seem like somewhat stupid or strict requirements, but they're things that worked for me and I figured I'd relay them to everyone. If you come out with results that aren't quite perfect just play with your printer settings and heat time as once I got those right things started to work a whole lot better and got some really nice results and a PCB which is ready for tinning and parts.
Step 12: Etching Revisited (October 24th edit)
To start I began looking at a few different etching tank designs and thinking about what I wanted out of my design. I came to the conclusion that I wanted something nice, but not overly expensive and building my own setup was the best option. As such I took a plastic cereal container that I found lying around the house and decided to use it as my tank base. This container is nice because it's large enough to fit bigger boards and has a snap on airtight lid, but not too large that it takes a whole gallon of etching solution to fill. From there I visited the local pet shop and purchased an air pump, some plastic tubing, a bubbling rock, and a small aquarium heater. With all the materials together I hot glued the bubbling rock into the bottom of the container and the plastic tubing up the wall of it. Finally I inserted the heater and was ready for the etching solution.
My second improvement was to heat the boards hotter and set the ink better in hopes it would adhere to the boards better. This was an easy fix as I found a coupon for a dual temperature heat gun at Harbor Freight Tools. This heat gun cost me $10 and has two settings of 570 degrees (F) and 1110 degrees (F) or so. This is more than enough heat as through some research I found the ideal heat for setting my ink is around 425 degrees (F). This is also great because at about 425 degrees (F) the copper clad board will start to turn a bit purple due to oxidation and the heat.
With my two problems solved I printed 2 new boards and tried out the new heat gun. This is where I must issue a warning. As much as you may think the higher 1110 degree (F) setting will heat your board faster and set the ink more easily do not try it. If you heat the board too fast it will warp. If you heat it too much, as I did with my first board, the adhesive holding the copper to the board will melt and the copper will bubble up. All that bubble took was a second on 1110 degrees (F) and the copper popped off.
My second board however I was patient with and used the 570 degree (F) setting and slowly heated the entire board until it started to turn purple. I tried to take an image of this for reference, but it's not visible on camera so you just have to keep your eye on your boards as you do this. Once the ink was set at this higher temperature I fill up my etching tank with some Ferric Chloride and let it heat up and bubble for a bit. When the solution was nice and warm I dipped my board into it and checked it every 30 to 40 seconds for progress. After about 3 minutes my board was done etching. (This type of tank and etching method is so much faster than rocking a container around by hand so I'd recommend the upgrade to everyone.)
After my board was complete I rinsed it off and took some pictures for this page. As you can see these two tweaks in my method produced results that are significantly better as this board has crisper traces and none of the pinholes that plagued the first few boards that I etched.
Step 13: Results
With that said you can see from the images that I'm getting some very good results now that everything is sorted out. I've reprinted and etched the Ethernet Arduino with ferric chloride and it is now waiting for parts that I ordered from Digi-Key. I think that compared to other ways I've etched PCBs in the past this method has had it's initial drawbacks, but now that things are in working order I think it will be a simpler, more consistent, and more reliable system. Rather than drawing out all of the traces with a marker or worrying about the heat and pressure of an iron in the toner transfer method I can now simply print my PCBs once and drop them in some ferric chloride.
Hopefully you've found this Instructable informative and helpful (If so please remember to vote for me in the Epilog Laser and Hack It Challenges) and are considering building your own Epson PCB printer. If you have questions feel free to ask me here or on my website and be sure if you do build something that you post a comment or a link so everyone else can see your skills and possible improvements.
On the subject of the Epilog Laser Challenge I really hope you consider voting for me as I feel the combination of this PCB printer and an Epilog laser cutter opens some serious doors for future projects which I hope to post to Instructables. I also hope to find more hackers and modders in my area to collaborate with on projects and I think a laser cutter could not only serve me well, but others I may meet in those collaborations.