[Abhimanyu Kumar] was watching YouTube videos one day when he came across something called a Polariscope — After learning how it worked, he discovered you can make your own using household items!
First off, what is a Polariscope? Well, put simply, it is a device that can show you the photoelasticity of a clear specimen, which can reveal the stress distribution in the material! And it is actually really easy to make one.
All you need to build your own is:
- A polarized light source (any modern LCD monitor)
- A transparent specimen (plastic cutlery, glass statues, plastic you can bend, etc)
- A circular polarizing filter (the cheap 3D glasses you didn’t return at the theater)
Then just place the objects in the order shown in the diagram and start snapping some photos. This would be really cool for checking stress concentrations in a project — provided you are using some Lexan or acrylic!
If you’ve gone to the trouble of building your own CNC mill we know you’re always on the lookout for things to use it for. [Boris Landoni] wrote in with just the thing for the holiday season; a set of lighted acrylic Christmas ornaments.
One of the interesting properties of acrylic is how it reacts when edge-lit. The material pipes the light, until it bounces off of a disturbance in the surface. The first step is to design the outline of the ornament as all cut edges will glow. Next, [Boris] uses artCAM to design the internal parts to be cut. This application translates the relief cuts necessary to really make your design shine (sorry, we couldn’t resist). The best examples of this are the angel and candle seen above.
Each of these acrylic pieces has a slot cut on the bottom to hug an LED. [Boris] used small project boxes with a PCB for that diode, as well as a button battery for power.
[Alan] acquired a stereo microscope from eBay, and decided to save some more money by designing, machining, and assembling his own
arc reactor ring light to go along. After finding an LED driver board sitting around as well as ordering some surface mount LEDs, he set about using a lathe to cut away a block of lexan, making sure to include slots for the lights as well as the microscope mount point. Follow the link to see the detailed build photos, as well as some comparison shots with and without the ring light.
A month or two earlier though, and [Alan] would have had a fantastic start to an Iron Man costume.