I was honestly surprised by how much attention the previous post about this rechargeable budgie shower received, and I really appreciate all the feedback. So I decided to write a more detailed technical recap about the path from the initial idea to a usable version. This post is a bit longer, with an estimated reading time of about 5 to 7 minutes. I will mainly cover four topics: why the pump design changed several times, why magnetic coupling and quick-release parts matter, how the ring shower head was optimized for support-free printing, and the final noise reduction, runtime, and real cage testing. At first glance this project looks like a small pet bird accessory, but once I started building it, the real challenges became very engineering-focused: the pump had to be strong enough, the structure had to be easy to clean, the shower head had to print reliably, and the sound could not be too scary for the birds. 1. The pump was the core challengeMy first prototype used a small centrifugal pump with a 22 mm impeller. Early feasibility testingThe result was far from the head height I needed. At 3.7 V, a 400 rpm N20 gear motor could only lift the water by around 1 cm, which was clearly far too slow for this centrifugal pump. A 030 motor performed better, around 6 to 7 cm, but it was still not enough. After that, I tried several directions: improving the centrifugal pump body, increasing the impeller size, using a planetary gear set to increase impeller speed, and testing a peristaltic pump. The peristaltic pump sounded promising because it can move liquid steadily and depends more on torque than high speed. In practice, however, the kit motor did not have enough torque to squeeze the silicone tube when directly driven. Even adding extra gear reduction to increase torque did not work well enough.This is a very useful tool for designing planetary gears. Click the image to go to that page. Eventually, I returned to the mechanically simpler centrifugal pump and redesigned the pump body. The key changes included the planetary gear set, a better volute shape, a slightly larger impeller, and an integrated printed water path. The integrated water path removed one connection point, reducing the chance of pressure loss and leakage while also making the structure cleaner.volute-shaped water pump housing2. Magnetic coupling and quick-release parts are for maintenanceOne of my favorite parts of the final design is the magnetic coupling. The motor module stays outside the water tank, while the impeller inside the tank is driven through the wall by magnets. This keeps the water and electronics better separated, and it also makes the power module much easier to remove.The power module, water tank, and printed filter are all designed as quick-release parts. The filter became especially important during testing: after about 90 minutes of continuous running, one shower hole stopped flowing. At first I was not sure whether the battery voltage had dropped or the pump performance had weakened. After checking, it turned out to be a small piece of debris blocking the hole. Once removed, the water flow recovered. Magnetic coupling also introduced a small but important detail: the distance between the magnets matters a lot. I found that magnets from different sources can have noticeably different strength. Stronger magnets may need a larger gap to avoid extra friction between the impeller and the base, otherwise the pump efficiency drops. 3. The ring shower head was optimized for support-free printingBesides the pump itself, the shower head also needed several design adjustments specifically for 3D printing. The ring shower head has internal overhangs. If modeled directly, the wall paths near the small holes can become completely unsupported, and the overhang length around the larger ring is uneven, which can cause poor local top-surface quality.So I did not design it only from the visible geometry. Instead, I checked the slicing paths and adjusted the model around them: large unsupported areas were converted into shorter, more controllable bridges, so the toolpath could span them more reliably. This allows the ring shower head to print very well without supports, with much simpler post-processing.This idea is also something I learned from the community. For some suspended-hole structures, changing the surrounding geometry can turn a completely unsupported toolpath into a short bridge that the printer can handle. This ring shower head is a further application of that technique, because the issue is not just an exposed circular hole. The overhangs are inside the water path and shower chamber.This detail may not be very obvious, but it matters a lot for print reproducibility. Because these overhangs are inside the ring shower head, enabling supports cannot really fix the problem, and post-processing would be almost impossible to clean properly. This part had to be designed for support-free printing from the modeling stage, instead of leaving the issue to slicing or cleanup. 4. Noise and runtime decide whether birds can actually use itAfter the pump finally worked reliably, the next question was whether it would be comfortable enough for the birds.In the first full test, the water output was already good, but the noise was still a bit too loud. I tested TPU parts to see whether softer material could absorb some vibration. The best result came from printing only the gear ring in TPU. The noise dropped noticeably, close to or even slightly below the sound of water dripping into the tank, while the water output did not noticeably decrease. I also tried replacing more drivetrain parts with TPU, but that made the water flow much weaker. So the final version only uses TPU where it helps the most, instead of making the entire drivetrain soft. The runtime was better than I expected. On a full charge, the shower ran continuously for more than 250 minutes before the continuous stream gradually turned into dripping. Of course, actual runtime can vary depending on printed-part friction, lubrication, magnet strength, and battery condition. During the first real cage test, both birds were cautious at the beginning. One of them started approaching and interacting with the water after about 20 minutes, while the other needed more time before joining. That reminded me that getting the mechanism to work is only the first step. The real user experience matters too. I tried leaving the water pump off and just hanging the shower outside the cage for a day or two to give them time to get used to it. After that, when I turned the pump back on, they almost immediately came over to play in the water. But there are individual differences among birds, so I can't say for sure if every one will do this LOL.This project started as an entry for the Rechargeable Power Kit Challenge, but it became a broader exercise in small pump design, magnetic coupling, support-free printing, noise reduction, and bird behavior. My biggest takeaway is that there are many small details hidden between "it moves" and "it is actually usable." Model link: https://makerworld.com/zh/models/2934071-budgie-shower-spa-mini-bird-bath-fountain#profileId-3285052

I designed this rechargeable parrot shower for my two birds. The original idea was simple: many parrots enjoy bathing, but a normal water bowl is easy to spill, and manual misting is not always convenient. I wanted to make a small shower that could sit inside the cage, run from the Rechargeable Power Kit, and be easy to clean after use.The final design is built around four main ideas:a quick-release power module, water tank, and printed filter for easier cleaninga magnetic-drive centrifugal pump, so the motor stays outside the water areause a ready-made transparent plastic sheet, as this will yield much better results than printing a transparent model.modular shower heads, so different water patterns can be swapped laterThe hardest part was the pump. I first tested small centrifugal pump prototypes, but the early versions did not provide enough head height. I also tried a peristaltic pump, but with the kit motor it had too little torque and the water output was small and uneven. After several rounds, I returned to the centrifugal pump idea and improved the pump body, added a better volute shape, enlarged the impeller slightly, and integrated the water channel with the printed body to reduce leakage and pressure loss.a early prototype Noise was another important challenge. Since this is meant for birds, it should not sound too harsh inside the cage. I tested TPU parts and found that using TPU only for the gear ring gave the best result: the noise dropped a lot, while the water output stayed almost unchanged. Printing more drivetrain parts in TPU reduced performance too much, so I kept the softer material only where it helped most.test with different materialsThe current version has passed full assembly and real-use testing. In one endurance test it ran for more than 250 minutes on a full charge before the continuous water flow gradually became dripping. Actual runtime may vary depending on print quality, lubricant, friction, and battery condition. I also added a filter after noticing that a small piece of debris could block one shower hole during testing. This project went through more iteration than I expected: pump efficiency, gear ratio, water sealing, magnetic coupling distance, noise, clogging, and shower hole spacing all needed adjustment. The latest shower head uses fewer, slightly larger holes than an earlier version, because dense water streams could merge together.I hope this design is useful for other bird owners and also interesting for anyone exploring small printed pumps and magnetic-drive mechanisms. Model link: https://makerworld.com/zh/models/2934071-budgie-shower-spa-mini-bird-bath-fountain#profileId-3285052

When designing CyberCrawler, I wanted to create something that felt halfway between a small RC car and a walking robot creature.Instead of focusing on overly complex mechanics, I wanted to make a robot that is fun to watch, fun to control, and approachable for makers who want to explore robotics without advanced tools or soldering.CyberCrawler can switch between two movement modes: Crawl ModeThe robot walks using four legs, each with only 2 degrees of freedom. Keeping the structure simple was an intentional design choice — fewer moving parts means easier assembly, easier maintenance, and more accessible code for beginners.It supports multiple gaits including:* Trot * Walk * Ripple * Single-leg gaitVehicle Mode The legs fold into a wheeled driving configuration, allowing the robot to move more efficiently like a small RC vehicle.The steering system combines Ackermann steering geometry with differential steering, which gives the robot surprisingly smooth turning behavior for such a compact design. One of the most interesting parts of this project was balancing simplicity and personality.I didn’t want it to behave like a traditional “serious” robot. I wanted it to feel playful and creature-like.At one point, I felt like the robot was still missing something emotionally, so I added a few simple interactive motions to the idle mode, including a controllable waving gesture and body-tilting movements. Those small motions surprisingly made a huge difference — the robot immediately started to feel more alive, expressive, and fun to interact with.To improve stability, I added an MPU6050 IMU for basic posture correction and tilt detection. If the robot tilts too far, it automatically enters an emergency mode that disables all servos and flashes a red light. The entire robot can be assembled without soldering, making it much more beginner-friendly for people interested in DIY robotics and STEM learning projects.Another important part of the design was keeping the code structure relatively easy to understand compared to many robotics projects. Because each leg only has 2 DoF, the gait controls stay lightweight and approachable for learning purposes. I especially enjoyed watching the robot switch between crawling and driving modes for the first time — that was the moment the whole project finally felt alive. Model page: https://makerworld.com/en/models/2849903-cybercrawler-dual-mode-wheeled-legged-rc-robot#profileId-3178494Source code: https://github.com/Teraen/CyberCrawlerMPY