Artistic Soldering with PCBs
Artistic soldering is something that I always used to point out to people on SparkFun tours. It’s a cool niche artform in the geek community. I’m always fascinated by the artistic soldering projects that I’ve seen. They tend to be cute and/or extremely robotic, but they weren’t always necessarily robots. I knew a guy who would make solder bears. (A real trick because the instant you heat up any single area the whole thing tends to turn into a pool of molten metal.) They were little tiny expressions of creativity formed with a substance that is widely used in an industrial fashion that is usually anything but artistically creative. (Bear with me here, I consider the design of electronics an art form as well as an engineering feat but the production process, especially when it comes to solder, can be a little repetitive and tedious for techs and QC people.) The soldered dragons, airplanes, scorpions, bears, tiny terminator hands (out of LED leads!), spiders, vehicles and numerous bots in the back of the SparkFun classroom always got a smile out of everyone.
I often took a moment at this point in the tour to explain to people how artistic soldering can help familiarize a new student with both the tools and the materials. It’s also a wonderful way to reuse faulty or excess PCBs and components. When artistic soldering with electronics, whether using Plated Through Hole, Surface Mount Device or other connectors (the finer points of BGA doesn’t really come into play with artistic soldering) I am often surprised by the various heat sink capabilities of the materials I work with. I’m well aware that the ground pour is going to take a lot more time to heat up than any of the other vias and I learned that when working with structural wires it’s best to run them across a bunch of SMD pads (pics below) or even back and forth. But I also often consider doing things that engineers would cringe at and find myself in funny cramped angles trying to apply heat and solder. Sure. My current project (at the bottom of this post) looks a little like a Gary Larson character. But I hope to fix that with an interior structural material of some type. (Suggestions welcomed.)
Here are a few tips and tricks I’ve learned-
Workspace– You’ll need all the standard soldering tools as shown below. I like to work outside if it’s nice. I also use this metal spider that I welded together as a stand for my projects. My Buckyball magnets make a nice malleable support structure that I tend to hand between the spider’s legs depending on where my project needs support. For most of the time you’re building a project it will need some sort of support structure. The spider and magnets are what I use, but I can see styrofoam (as long you don’t burn it) or a bunch of third hands working as well. If you’re working inside make sure that your workspace is well ventilated,
Threading– If you can find panelized circuit boards like the pro mini reject boards below (no, I don’t know why they are rejects, they were just lying around) then you can do something I call, for lack of a better name, “threading.” I should call it something like “The Hyena Striking Cylone Method,” but alas, I am dull and witless so I refer to it simply as “threading” in this post. You wind up with some scrap wire at the end of this process, but I think it’s much faster than what I was doing in the beginning- soldering the pieces together one by one.
Sometimes you’ll come across a section of multiple boards that have yet to be depanelized. Leave these guys together, it’s an opportunity to lace wire through the vias (the little holes around the edge of these little circuit boards) to make your connections.
Pull the wire through the via, from the other side of the board. This will make the wire lie flat against the PCB. Weave the wire through the various vias in such a way that there is wire bridging all the splits between the PCBs. Normally this is where the PCBs would be broken apart into several separate smaller pieces. In this case eventually it is broken apart, but not into separate pieces.
This will leave some wire across the boards where you don’t necessarily want wire. That’s ok, you can clip that off later.
Having trouble getting the wire to lie flat on both sides of the board? Don’t worry about it. Sometimes it’s hard to pull the wire all the way through the via due to kinks or weird angles. In that case I often use a pair of pliers or wire cutters (using the wire cutter’s plier surface) to pull the wire the rest of the way through.
I like to solder my joint on the underside of the PCB surface, that way the soldering is on the bottom, where it’s harder to see. Pay very careful attention when “threading” to make sure that the wires that are left after you snip off excess are all on the same side of the PCB. (These should be the sections of wire that are crossing over the cracks between the PCB sections.) This may or may not matter to depending on your aesthetics and what you’re building. That’s the cool thing about artistic soldering, there is no one correct way to do it! It’s art.
You may also want to leave a loop of wire at the edges of the section of PCB you are threading together. That way you already have wire when you go to attach this smaller section of PCBs to the rest of your project (or vice versa). Note how I am careful to leave vias free in strategic positions to make connecting all the PCBs easier. If you concentrate only on the PCBs you are currently threading you may wind up having to use vias that aren’t in the most ideal locations when you are connecting more PCBs in the future.
Got your board all threaded up? Ok, go ahead and solder all the joints. Make sure you’re applying solder only to one side of the board if you’re concerned about that type of aesthetics. Also bear in mind when soldering “threaded” joints that applying heat to one of the solder joints will eventually apply heat to all of them since the heat travels through the wire. This may make the soldering take a little more heat than you’re used to. That’s just fine. The other thing to remember is that the quality of the solder joint doesn’t matter nearly as much with artistic soldering as it does with technical soldering. Just make sure you don’t pull any of the metal off of the PCBs by accident in the process, something that is commonly referred to as a “pulled pad” or via.
Next up is clipping the wire. Make sure to wear safety glasses while doing this. If you ever get metal lodged in your eye you have to actually watch the doctors drill away part of your eyeball. Not a fun process from what I’ve heard. Clip off the excess wire on the underside of the PCB panel (making sure not to clip the wires that cross the splits between boards) if you don’t want people to be able to see them. Make sure to clip as close as you can to the PCB without putting too much stress on the solder joint as that may result in a pulled pad or via. I also tend to clip the loops of wire on the exterior of the panel as shown in the second image above.
Now, as gently as you can, break the board sections apart. You’ll want to make sure you don’t bend the wire over and over during this process since any bending of the wire introduces stress to it’s structure and may result in breakage. If you did it right you’ll have some sort of a two dimensional plane that you can bend into various different shapes. If the wire holding your PCBs together are different lengths you can get different three dimensional effects.
As a result of my efforts I’ve got a small plane of PCBs that I can gently form into a variety of shapes. Threading results in fairly structurally sound PCB objects. You just have to know where you can get your hands on an unbroken panel of PTH boards. Any pieces of wire that are left over can be reused if you’re
Wire gauge- I like to use a wire guage that is one step down from the size of the vias I’m soldering to. This way when the wire kinks up (as it inevitably will if you’re using any length over two inches) it will still pull through the vias. I also find that it will bend at a more acute angle closer to the solder joint. You may experience some issues with joint structural integrity, especially in 3-D projects that lack additional structural support. There are ways to rectify that.
Using panels of SMD boards– You can also create similar objects using panels of SMD PCBs but they tend to be less structurally resilient since the connections are all on the surface of the boards as opposed to running through the boards. I find that soldering the wire across multiple pads is the best way to get SMD boards to hold together when using them for artistic soldering. I know these solder joints aren’t the prettiest (and you can even see in the bottom center where I skipped a pad) but I’ve got my artist hat on, not my technician or engineer hat. Some people will add a little glue to their PCBs. I’m not saying that’s cheating.
Ideal PCB shapes for artistic soldering– I had a bunch of Luxeon Rebel LED breakout boards lying around with no bottom mask. Because of the missing layer of plexiglass the whole bottom of the board was exposed metal. That combined with the fact that the Luxeon board is a hexagon board maked them an artistic solderer’s paradise. I used male headers to connect the various boards together creating very tight, organic shapes, such as the above character’s chin, ears and portions of it’s forehead.
Using chips– If you’ve got a bunch of ICs lying around that you have no use for (my inner technologist cringes at this, but sometimes it happens) you can easily fit them together for use in artistic soldering as well. With ICs there is no need to use wire since the IC leads will mesh together and create a perfect corner of metal that is easily soldered together.
Soldering to non-connection surfaces of components– Again, engineers, get ready to cringe. Sometimes you may find that you need to solder to components in places that are not intended for soldering. That’s fine. All you need is a section of exposed metal that you can heat up enough so that the solder will stick to it. That means huge hunks of metal will be difficult to work with, but the majority of everything else is fair game. You can even use non-electronic metals in your sculpture. There is a long history of people doing artistic soldering with materials other than PCBs and electronics. Look it up! I’ve soldered wires to everything from a penny to scrap PCB stencil aluminum. Bear in mind that the penny will get really hot!
Where can you find PCBs?- It seems like people are more interested in selling their scrap PCBs than buying them. One of the few places I’ve found that actively sells scrap PCBs and electronics is SparkFun Electronics. You can also try approaching any local electronics producers or recycling centers. Chances are if you’re an educational organization interested in teaching artistic soldering these places will work with you to enhance their standing with the public while getting rid of PCB scrap. Why wouldn’t they? It’s a win-win situation for them if you present it in the right manner.
Finally, here’s a quick video of where my humanoid head project is at these days. I work on it occasionally when I need something low-key to do. I’ll write another post or put a finished pic and/or video in the comments once I’ve finished it.
As always please let me know if you’re into artistic soldering, caught any errors or have additional information in the comments below. Despite all my buddies at SparkFun who participate in this art form I haven’t really seen any of it at the Hackerspace, Makerspaces and other “Spaces” I’ve visited. (I can’t remember how many I’ve hit up, somewhere between twenty to thirty to date maybe? I dunno.) Other than Steve Rodrig (see link below) there doesn’t seem to be a huge online community either. I’d love to hear about your projects if you’re creating artistic soldering with electronics too! Maybe Make Robots Not War could even feature you and your projects? Reach out, it’s easy. I’d also love to learn from you because I’m sure you’ve developed techniques of which I haven’t even dreamt.
In case you missed it here’s a link to some really, really cool artistic soldering projects by Steve Rodrig as well as a site outlining some of the ways that people recycle e-waste.
Images by Linz Craig, additional images by SparkFun Electronics