Originally intended as a universal smart pump for my mill and my plants. I had one thread angled slightly so the stepper had problems to covercome a certain dead point. One solution was to drill the holes new and just glue two rods in perpendicular. Worked better than expected.
Now I need to draw a new closed housing and get the electronics a bit more watertight.
Sometimes the best ideas are simple and seem obvious after you've heard them. [Danny] showed us a great idea that fits that description. He uses a peristaltic pump to move resin in and out of his print bed. (Video, embedded below.) Normally, you remove the tank and pour the resin out into a container. With the pump, you can leave the tank where it is and simply pull the resin through a tube. The process is slower than pouring, but not as messy and doesn't risk damage to your FEP film.
You can also use the pump like a vacuum to clean up resin. According to [Danny], the biggest value is when working with very large printers. He shows a Peopoly Phenom which has a huge tank compared to the other printers he shows in the video.
The cost for the pump is less than $40, although you can get faster pumps for a higher cost. [Danny] didn't think it was worth the extra cost. Depending on the size, the less expensive pump will empty a tank out in 5 to 10 minutes. He also had a few tips about how to get the best flow and make the least amount of mess.
Once done, he pumps alcohol through the pump and caps off the tubing using a bolt. Overall, it looks like a great trick. You can, of course, make your own. We see them bartending quite a bit.
Stout Peristaltic Pump Fabricated From Scratch
The peristaltic pump is perhaps most well known for its ability to pump fluids without the pump mechanism coming into contact with the working fluid. This is key for food-safe applications and other situations where a pump could contaminate the fluid. [Maciej Nowak] has built a great example of such a pump, crafted out of aluminium from scratch.
The build video covers the machining process in detail, showing how the aluminium body was fabricated on the lathe before installing bearings and a silicone hose. The pump shaft was then fabricated, along with a set of brass rollers to press along the tube, creating the pumping action. The rollers were also lubricated in order to reduce friction on the tubing. Powering the pump is a small DC motor, sending drive via a small toothed belt, giving the finished build quite an industrial look.
We're used to seeing plenty of 3D-printed pumps about the place. This build, while it requires a fully-equipped machine shop, is much tougher than anything plastic, and you could easily use it to break a window in an emergency too, an obscure feature nevertheless requested by some discerning pump customers.
[Maciej] shows off the build by pumping some green liquid, noting the peristaltic design requires no priming which makes operation much easier. It's also bidirectional, and can be run very slowly if required.
Overall, it's a build that shows off the benefits of working in metal as well as the great features of the peristaltic pump design. Video after the break.
The Silent Dripper Dispenses Water Without Making Any Sound
Engineering is all about making a design that conforms to a set of requirements. Usually those are boring things like cost, power consumption, volume, mass or compatibility with existing systems. But sometimes, you have to design something with restrictions you might have never considered. [Devon Bray] was tasked with designing a system that could dispense single drops of water, while making absolutely no noise. [Devon]'s blog describes in detail the process of making The Silent Dripper, which was needed for an art installation called The Tender Interval by [Sara Dittrich].
The design process started with picking a proper pump. Centrifugal pumps can be very quiet due to their smooth, continuous motion, but are not suitable for moving small quantities of liquid. Peristaltic pumps on the other hand can generate single drops of liquid very accurately, but their gripping-and-squeezing motion creates far more sound. [Devon] still went for the latter type, and eventually discovered that filling up the pumping mechanism with lithium grease made it quiet enough for his purpose.
The pump was then mounted on a 3D-printed bracket that also contained the water feeding tube and electrical connections to the outside world. The tubing was fastened with zip ties to stop it from moving when the pump was running, and the pump itself was isolated from the bracket with rubber dampening mounts.
Another trick to silence the pump was the motor driver circuit: standard PWM drivers often cause audible whine from the motor coils because of their abrupt switching, so [Devon] went for a Trinamic SilentStepStick that regulates the current much more smoothly. The end result is a water dripper that makes less noise than a piece of tissue paper being crumpled, as you can observe in the video (embedded below) which also demonstrates the complete art installation.
We really like the mechanical design of the Dripper; as far as we're concerned it would merit a spot in a gallery on its own. It would not be the first water dripping art project either; we've already seen a sculpture that apparently suspends droplets in mid-air.
Automated Watering Machine Has What Plants Crave: Fertilizer
We've seen countless automated plant care systems over the years, but for some reason they almost never involve the secret sauce of gardening -- fertilizer. But [xythobuz] knows what's up. When they moved into their new flat by themselves, it was time to spread out and start growing some plants on the balcony. Before long, the garden was big enough to warrant an automated system for watering and fertilizing.
This clever DIY system is based around a 5L gravity-fed water tank with solenoid control and three [jugs] of liquid fertilizer that is added to the water via peristaltic pump. Don't worry, the water tank has float switches, and [xythobuz] is there to switch it off manually every time so it doesn't flood the flat.
On the UI side, an Arduino Nano clone is running the show, providing the LCD output and handling the keypad input. The machine itself is controlled with an ESP32 and a pair of four-channel relay boards that control the inlet valve, the four outlet valves, and the three peristaltic pumps that squirt out the fertilizer. The ESP also serves up a web interface that mimics the control panel and adds in the debug logs. These two boards communicate using I²C over DB-9, because that's probably what [xythobuz] had lying around. Check out the demo video after the break, and then go check on your own plants. They miss you!
Don't want to buy just any old peristaltic pumps? Maybe you could print your own.
#lifehacks #microcontrollers #arduino #arduinonano #automatedplantcare #automaticplantwatering #esp32 #fertilizer #lcd #peristalticpump
Thomas 🇪🇺
hackaday unofficial
harmoniemand