Synthwave Build Log
This guide will walk you through each step of building Synthwave, the world’s first open-source Direct Ocean Capture device.
Please note that while I’ve tried to keep this document as up-to-date as possible, there may be gaps or inaccuracies due to underlying changes in the hardware. If you run into something, please feel free to reach out for help via this forum or the OpenAir Discord.
Prepare components
If you haven’t already, source all of your components via the official Bill of Materials.
Also, make sure you’ve finished 3D Printing the following parts:
- Base
- Pump brackets (you’ll need two of these)
- Top shelf
- Container cover
This tutorial also assumes that you’ve already populated your PCB. I haven’t produced any tutorials on how to do this yet, although experienced builders should have no problem simply matching the holes up to the various components.
If you’re interested in building a Synthwave, but aren’t experienced with PCBs or soldering, I would be happy to ship you a prepopulated board for the cost of materials*. This will likely save you many hours during the build process.
*If enough people take me up on this, I’ll need to also charge for labor. But for now, you get that for free 
Three-way Solenoids
If your solenoids came with JST connectors attached, cut them off and expose a bit of the leads.
A nice thing about these solenoids is that the fittings can be rotated around. You’ll need to rotate two of them 180 degrees so that they mirror each other. Carefully unscrew the four Philips head screws, turn the plastic bit around, and screw it back together.
Two-way Solenoids
These solenoids are referred to as the “flush valves” in Synthwave. You’ll need to solder a red and black wire to each of the leads on the solenoids. I like to twist them together for aesthetic reasons.
Micro Pumps
Again, you’ll need to solder red and black wires to the leads. While you’re at it, attach the 3d printed pump brackets, and place set M2 screws in each screw hole.
Vacuum Pumps
Yep, you’ll need to solder wires to these as well.
32oz Deli Containers
These are the same kinds of containers you get from takeout restaurants-- Chances are you have a couple of them sitting around your house.
The only difference is that they need a hole drilled in the bottom. This is actually harder than it sounds, because these containers tend to crack or shatter. I found that by drilling through a layer of painter’s tape, it’s much more likely to leave a clean hole.
You’ll notice that the shape of the bottom isn’t perfectly flat: There’s a ridge around the outside that’s a little lower than the rest. Because of this, you may want to use a 3" hole saw to cleanly cut through this ridge. If a 3" hole saw isn’t available, just use the biggest bit you can find and drill right through the middle.
Begin assembly
PRO TIP 1: Do not overtighten! We are screwing straight into plastic, so don’t expect it to hold as well as wood or metal.
PRO TIP 2: When working with tiny, fiddly screws, I recommend magnetizing the tip of your screwdriver. Just rub a strong magnet against it for a while, and it’ll hold onto screws.
Start by affixing the solenoids and micro pumps to the left and right sides of the 3d printed shell, like so. I actually used M3 screws here, as they fit a little better. Make sure to take note which direction each of the solenoids is facing before you screw them in.
Next, attach the micro pumps and brackets to the shell. Then, screw the flush valves into the bottom of the shell. You should end up with something like this.
Because of the flush valves sticking out of the bottom, Synthwave no longer sits flat on a table and is therefore much easier to work on while sitting on a five gallon bucket. From here on out, I recommend using the bucket to prop up your device for stablilty.
Start heating up your hot glue gun. While it’s heating, screw in the the Luer lock fittings to the membrane contactor. Then, route the tubing to the upper solenoid, as pictured.
Now put a blob of glue on each side of the lower shelf area, then press the membrane contactor into it. Hold it still for at least 45 seconds.
Next, route the rest of the tubing.
NOTE: You’ll notice that there are two holes leading to the bottom of each container. In order to achieve a watertight seal, you’ll want to put a blob of glue inside the hole, then push the end of the tube through it from the outside in.
In order to not clog the tube with glue, you can stick a screw or small nail in the end before you push it through, then remove it when it’s in position. Done correctly, this will ensure that the glue surrounds the tube and creates a perfect seal.
Now, glue the containers in place. Make sure to use a significant bead of glue: Again, you want this to be as watertight as possible. At this point, you should have something resembling this:
Attach the 3d printed upper shelf using M2 screws. You can now press-fit the vacuum pumps into place, or if you prefer, glue them. At this point, you may turn off your glue gun.
