Some people really like puzzles. [Simone Giertz] is one of these serious puzzle lovers and built a transforming table (YouTube) to let her easily switch between puzzles and more mundane tasks, like eating.
While there are commercial solutions out there for game tables with removable tops and simpler solutions like hinged lids, [Giertz] decided to “make it more complicated and over-engineered than that.” A tambour top that rolls out of the way makes this a unique piece of furniture already, but the second, puzzle table top that can be raised flush with the sides of the table really brings this to the next level.
If that wasn’t already enough, the brass handles on the table are also custom made. In grand maker tradition, [Giertz] listened to her inner MYOG (Make Your Own Gnome) and got a lathe to learn to make her own handles instead of just buying some off the shelf.
We have all seen Printed Circuit Board (PCB) antennas: those squiggly bits of traces on PCBs connected often to a Bluetooth, WiFi or other wireless communication chip. On modules like for the ESP8266 and ESP32 platforms the PCB antennas are often integrated onto the module’s PCB, yet even with such a ready-made module it’s possible to completely destroy the effectiveness of this antenna. These and other design issues are discussed in this article by [MisterHW].
It covers a range of examples of poor design, from having ground fill underneath an antenna, to having metal near the antenna, to putting dielectric materials near or on top of the antenna. The effect of all of these issues is generally to attenuate the signal, sometimes to the point where the antenna is essentially useless.
Ultimately, the best PCB antenna design is one where there is no nearby copper fill, and there are no traces running near or on layers below the antenna. After all, any metal trace or component is an antenna, and any dielectric materials will dampen the signal. Fortunately, there is e.g. a free KiCad library with ready-to-use PCB antenna designs to help one get started with a custom design, as well as many other resources, covered in the article.
If you want to get really professional about checking the effectiveness of an antenna design, you’ll want to use a Network Vector Analyzer. These will also help you with tuning the capacitors used with the PCB antenna.
By first making a silicone mold of the vinyl record and then pouring several different colors of resin into the resulting mold, [Evan and Katelyn] were able to make a groovy-looking record that still retained the texture necessary to transmit the original sounds of the record. The resulting piece has some static, but the music is still identifiable. That said, audiophiles would probably prefer to leave this up on the wall instead of in their phonograph.
Acrylic rings were laser cut and bolted together to build the form for the silicone mold with the original record placed at the bottom. To prevent bubbles, the silicone was degassed in a vacuum chamber before pouring over the record and the resin was cured in a pressure pot after pouring into the resulting mold.
There’s something about light fixtures that attracts makers like moths to a flame. [danthemakerman] wanted something with a more configurable light output and built this Sculptural and Customizable Plywood Lamp.
In his detailed build log, [danthemakerman] describes how he wanted something “sort of like an analog dimmable light.” By using a stack of split plywood donuts hinged on a brass rod, he can vary the output and shape of the lamp. These shutters allow the lamp to go from bright to nightlight without using any electrical dimming components.
The plywood was rough cut on a bandsaw before being turned on a lathe. The light cover sections were then hollowed out with a Forstner bit and split in half. The tricky bit is the overlap of the cut on the hinge side of the shutters. Cutting the piece exactly in half would’ve required a lot more hardware to make this lamp work than what was achieved by patient woodworking.
It wasn’t long ago that we looked at easily creating Docker containers from the command line so you could just easily spin up a virtual environment for development. Wouldn’t it be nice if you could do the same for virtual machines? You can. Using Multipass from Canonical, the makers of Ubuntu, you can easily spin up virtual machines under Linux, Mac, or Windows. Granted, most of the virtual machines in question are variations of Ubuntu, but there are some additional images available, and you can create your own.
Once you have it installed, starting up a new Ubuntu instance is trivial. If you have a set configuration, you can even set up predefined setups using a YAML file.
When learning about the design of a machine or mechanism, reading and watching videos is certainly effective, but it’s hard to beat hands-on experimentation. In the video after the break, [Brick Technology] uses LEGO to gain some practical insight into the world of piston engine design, from single-cylinder all the way up to radial twelve-cylinder engines.
Using pneumatic cylinders from the LEGO Technic series, [Brick Technology] starts by getting the basics working with a single-cylinder design. Besides the fact that there are no fuel-air explosions involved, these pistons are also double-acting thanks to a valve mechanism that switches the pressurized side of the piston as it reaches the end of its stroke. After a couple of experiments, he settles on using a bank of six two liter soda bottles as a source of pressurized air.
He also increased the performance of the LEGO cylinders by drilling out the ports and adding silicon oil for lubrication. In the initial prototypes, the cylinders also acted as connecting rods, tilting back and forth as the crankshaft rotates. After some testing, he discovered he could increase efficiency by constraining the cylinder with a slider mechanism and adding a separate connecting rod.
With the basics done, [Brick Technology] could start experimenting with engine arrangements and geometry. Inline two, three, and four cylinders and V2, V6, V8, and even R12 were all on the menu. He could also change crankshaft geometry to trade torque for RPM and vice versa, and build a starter motor, and torque generator.
Just like [Brick Technology]’s LEGO electronic drums and vortex machine, this video gives us a itch that can only be scratched by a few hundred LEGO pieces. For rapid prototyping of course.