My wife has a lot of stuff she wants to sell online and asked me to create a sturdy but cheap Photography Light Box. The dimensions of the different objects vary, so I wanted to be flexible with the dimensions of the light box. We came up with a simple idea to create a three way connector that connects curtain rods. The frame will be covered with white bed sheet cloth kept together with velcro. At the local hardware store I found plastified steel curtain rods. These were the cheapest I could find but are still very strong.
My sons have large Lego minifig collections but most of it is lying in a large box. The older son wanted a cabinet so he could display (part of) his collection better. These cabinets can be pricey so I decided to make one myself. I’ve done some laser cut projects recently, such as the Darth Vader Chest Box and the Valentine’s Heart, so I decided to use the same technique for the cabinet.
A week ago I finished my audio cooler. Although I was happy with the result improvements could be made (as is always the case). Most important I didn’t particularly like the console on the side of the coolers lid. This was a 3d printed part of PLA that I glued to cooler with a superglue. This was far from ideal because of the space left between the printed console and the cooler . Another improvement could be made by the way that the speaker was fitted to the lid of the cooler. The speaker was directly attached to cooler with four screws again leaving some space between the two. I already had some FilaFlex filament but hadn’t used it yet. Because of the elastic and flexible properties of Filaflex I figured that I could both fix the issues with the console and the speaker.
A couple of weeks ago I started to make a tiny audio system for our cooler. In my previous blogpost I described all the audio components that I chose for this project. I wanted the components to be small since I didn’t want to waste too much space in the cooler. With the audio components in hand I could design other parts for the audio system. I needed an enclosure for most of the audio components and a simple console to operate the audio. The parts were 3d printed with my Hephestos 2.
The last couple of weeks I’ve been busy mastering 3D modeling programs and bringing my creations to life with my Hephestos 3D printer. In this entry I’ll share some of my creations and how they were made. For 3D modeling I started with OpenSCAD in the beginning of this year and later started using FreeCAD. The reason for using FreeCAD is that with more complex design in OpenSCAD it is easy for me to get lost in a large script. Yes, the learning curve of FreeCAD is steep but eventually it’s easier for me to create more complex models in this program than in OpenSCAD. For simpler models I still like OpenSCAD better.
I have a MK194 radio kit from Velleman and turned it into a radio some time ago. The radio looks pretty cool with all the electronic components visible but the wooden case was awful. I therefore decided to build a new case for it. Of course I want to use my Hephestos 2 printer from BQ to make this case.
First I designed a case in FreeCAD. I use FreeCAD for a couple of weeks now, together with OpenSCAD, but this is the first design with multiple parts that I create with it. After several iterations I finally decided to have a design consisting of three parts. A box, a support plate for the radio PCB and a lid. The radio fits into the support and the lid which are then screwed onto the box.
The box is by far the biggest 3D print that I made with the Hephestos. It took the printer almost seven! hours to print it. Luckily it came of fine the first time. Both the lid and the support plate were printed in less than an hour each.
What to make for Valentine’s day? A bare perfboard with a Valentine’s chaser (basically a 555-chip, 4017 decade counter and a handful of leds) doesn’t look too impressive. That’s why I made this heart shaped wooden box with a laser cutter. Both printboard and battery fit nicely into the box. Three bolts, nuts and washers to finish the job.
The file for the laser cutter (.svg) can be found here.
And here is a 3d printer file (.stl) of a little dock for the heart.
The last month I’ve been working on my Darth Vader chest box. I’ve designed and built my own circuit with the Holtek HT8950A voice modulator. I create a laser cut case and designed 3D printed parts for the chest box. Since I had to learn a lot of new techniques, e.g laser cutting and 3D printing, this is by no means an easy project for me. With the project in its final stages now some design problems turn up that need fixing.
Soldering the board.
This week I soldered the components to the board. First I soldered the voice changer components and made sure this part of the circuit is working. Next I soldered the amplifier. I tested the total circuit and it worked the first time which is always a joyful moment. I find the Adafruit perma-protoboard very easy to work with since I’m able to copy the layout from the breadboard. Next I grouped all the buttons that operate the HT8950A on a board and soldered them to a piece perfboard. The buttons on the perfboard fit nicely into the laser cut side panel that I already made. Operating the chest box is easy with this (a major issue with my previous chest box).
Last week I made 3D printed parts for the front of the chest box. Unfortunately I found that these parts didn’t look good with the laser cut box. The plastic parts just didn’t do justice to the laser cut plywood. I therefore decided to laser cut all the parts that sit on the from of the box with I think is aesthetically more pleasing.
Another problem arose with the female audio jack connector that I need to plug in the microphone. The thread of this 3.5mm connector just isn’t long enough to be fitted onto the 6mm thick plywood. I designed a container to solve this. The audio connector fits into this container and the container is screwed to the case. The .stl file can be downloaded here: https://my.hidrive.com/lnk/RKCIiaQ2. Hopefully this container solves the problem.
Yet unsolved problems
I need to attach a nylon belt to the chest box. I’m thinking about popper snap fasteners attached to the belt to open or close the belt.
The HT8950A works fine with a proper audio signal as input but the microphone that I have, a small electret microphone, doesn’t give any audible output (except for noise). I assume that the signal is too weak and therefore needs amplification.
Here are the links to all blog posts I wrote about this chest box:
A new year, a new beginning. Last year I took a fair interest in technologies like laser cutting and 3D printing but I still relied on my old 20th century skills for my projects. Investment in time to master these new technologies was holding me back to advance in both laser cutting and 3D printing. In the very last month of 2015 I took the decision to produce a case with a laser cutter. It was a revelation. A job that would normally take me a day or so was done in a matter of minutes with a precision that I can never achieve with the old saw and chisel. From that point on I decided to invest heavily, in both time and money, in these new technologies.
First I learned to work with Inkscape, a free 2D vector drawing program for laser cutting. I discovered that it is a good tool for illustration (e.g for web design) too. Next I needed a 3D design tool to create parts with a 3D printer. I looked at different programs such as Sketchup, 123D Design but I increasing dislike the proprietary character of these programs. Echoing the words of Richard Stallmann “the proprietary program is a system of unjust power”. On the non-proprietary side there is FreeCAD and Blender but I found the learning curve of these programs too steep. Then I discovered OpenSCAD when reading an article on Hackaday. It’s a free (as in free beer and free speech) program running on Windows, Linux and OSX that has a great community. Instead of using a point and click interface the user has to script his models with a descriptive programming language. This seems strange and cumbersome at first but it actually works for me. I found it very easy to get into. OpenSCAD is very lightweight. Other CAD programs tend to be a burden on a PC but OpenSCAD runs even on low spec machines. Because of the script that OpenSCAD uses it is very apparent what is in the 3D model and what the dimensions are. The comparison with HTML comes to mind. Therefore it is possible for anyone else to see how a model is made, learn from it and make changes to it.
Parts for the voice changer
The Darth Vader chest box has a very distinctive look with lots of distinctive buttons and other parts (see images below). I modeled these parts with OpenSCAD beginning with the simple buttons working my way up via the coin slots to the complex rods. I’m satisfied with the result thus far. Next I’ll 3D print the parts and glue them to the plywood chest box I made earlier.