Introduction: Articulo: Hacking a Radio for Tradesmen and Outdoor Labour
Working outdoors can be demanding. From tree surgery to construction, the list of conditions in which workers must take on is endless. The equipment these workers use during everyday tasks must be suitable to withstand this heavy usage.
Articulo is a new take on the traditional 'tradesman's radio', incorporating durability, functionality and aesthetics into one package. Through the use of a flexible middle section the device can be wrapped around, hooked on or otherwise attached, securely, to its surroundings. Simple twist controls operate the volume and station settings, these are easy to use and are less vulnerable to damage from build up of dirt. A large push button on the end of the device allows easy on/off. Articulo is made to last, employing a tough weatherproof outer casing to ensure it is as durable as it is functional.
Step 1: Materials List
To construct the Articulo radio you will need the following materials:
- 300mm length of 100mm internal diameter white piping, 2-3mm thick.
- 700mm length of 50mm diameter aluminium semi rigid ducting.
- Large sheet of 2mm white styrene (exact amount will vary with different vacuum formers)
- 800mm2 of 9mm mdf,
- 200mm of 12mm diameter doweling
- 200mm of 8mm diameter hollow metal piping.
- 6 x ball bearings (internal diameter: 12mm, external diameter: 28mm, width: 8mm)
- Epoxy resin
- 44x 45 block of pine.
Step 2: Dismantling the Radio
Due to the nature of the casing design I found that its easier and more efficient to construct the radio shell before assembling the finished electronics. A lot of the wiring also needs to be fed through the length of the radio, which may damage any pre-soldered connections. This in mind, disassemble the radio removing the speaker, volume control and tuner so the electronics are ready to be finished upon creation of the casing. No need to start any desoldering yet, simply remove the components from the existing casing, so they are easily identifiable when the time comes to work on the electronics.
To construct the curved end pieces of the radio casing you must first turn the high density foam (or other) to a cylinder of diameter 100mm. From here start to work the cylinder into the curved shape shown, aim to work the curve until a diameter of 50mm is reached at the end of the mould. Once you are happy with the rough form, go over the rough turned shape with various grades of sandpaper to remove any irregularities and achieve a smooth and even finish suitable for vacuum forming. Next cut to a length of 70mm, giving the shape below.
Next, cut a small piece of the plastic piping (about 8mm) and slip this over the foam mould, filling in the gap between the two with clay. When formed, this creates a tight joint that slots neatly onto the pipe, avoiding any nasty joints between the piping and curved end pieces and allowing easy access for working on the electronics. One this is done, you are now ready for vacuum forming. Cut the styrene to the required size for the machine you are using and get forming!
To remove the mould you may need to drill a small hole in the end of the plastic (as seen below) to allow air between the two surfaces.
Once the mould is removed you are ready to cut the plastic shape to side. Trim as much excess plastic off with the plastic band saw as possible then sand flush and smooth with a high grade sand paper.
Step 5: End Caps
To cover up the flat ends of the tubing, simply vacuum form a low profile cylinder using the same thin piece of piping used as a guide earlier filled in with clay and flatten in off with a straight edge. As before trim with a band saw the sand with a hand sander to finish.
As the curved ends, these will slot snuggly onto the tubing.
Drill a 48mm diameter hole in one of the two cylinders for the speaker to be mounted to. The speaker can be mounted to the inside of the hole using epoxy resin.
Step 6: Cutting the Piping
Next, the piping must me cut into lengths to form the twist control end of the device and the end housing the circuit board and speaker. Cut the piping on a band saw taking care to keep the tubing is perpendicular to the blade, then smooth them off using a hand sander.
You will need to cut the following lengths of pipe:
- 3 x 30mm sections
- 1 x 40mm section
- 1 x 130mm section
These lengths of piping will be slotted over a selection of wooden disks to form the basic structure of the casing.
Step 7: Central Axis
The central axis allows the two twist controls to rotate independently whilst still being on the same axis. It consists of a hollow cylinder that houses 4 bearings which are attached to two separate rods. The cylinder holds the two rods inline and on the same axis, but separated slightly in the middle allowing, in conjunction with the bearings, the rods to rotate individually.
To create the cylinder, sand the corners of the piece of pine to create a cylinder of dimeter 44mm x 45mm. Using a pillar drill, drill a hole of dimeter 28mm all the way through and slot in the 4 bearings. Feed the two rods in, through the bearing at either end, adjusting accordingly should they touch in the middle.
Step 8: MDF Disks
The bulk of framework for the shell is constructed from a series of MDF disks, all of which are sized diameter 100mm to slot snuggly inside the sections of plastic piping,
Mark out the MDF with a total of 7 disks diameter 100mm. Use a band saw to cut out the rough shape of the disks then finish to size using a disk sander. The disks must be cut and sanded accurately in order to fit snuggly in the piping.
Now two pairs of the disks and glue them together to form two separate 100mm x 18mm disks. These thicker disks are the twist controls that will later be attached to the tuner and volume adjusters.
Once the disks are cut to size you can start drilling the holes to house the bearings and the central axis. In two of the 100 x 9mm disks, drill a 28mm hole in the centre to house the bearings. In the two 100 x 18mm disks first drill a 11mm hole for the rods, followed by a 48mm inset 8mm deep. This inset hole slots around the central axis without touching it, allowing the rods to move freely.
Step 9: Twist Control Diss
To prevent all of the disks (including the end disks) spinning independently, and restrict movement to only the controller disks, an additional rod must be added to hold each end of disks at either side together. In order to do this a slit must be cut in the the controller disks to allow them to spin freely without hitting this support rod. The tube is 8mm in diameter so a 12mm wide arc must be cut to allow enough space.
First drill a 12mm hole in the disk then thread it into a finely bladed band saw to cut out the arc. As these discs are totally concealed they can be cut by eye so long as the width remains above 12mm.
In the two thinner disks, drill an 8mm hole in line with the specially cut slit.
Step 10: Frame Assembly
Once all the disks are completed the frame can be assembled as bellow. You are now ready to complete the electronics.
Step 11: Flexible Middle
Unfortunately due to a problems with my courier the aluminium ducting i ordered did not arrive on time for my uni hand in, so I have had to compromise and use flexible plastic tubing purchased from the local DIY shop. Though not strong enough to support the radio as the ducting would have been, it demonstrates the concept and gives an idea of what the final product would look like.
The tubing was cut to 700mm length and glued to the casing using epoxy resin.
Step 12: Electronics
Now that all the components in the shell are completed the electronics can be constructed.
First of all the volume adjuster and tuner must be carefully desoldered and removed from the circuit board. They must then be extended with roughly 1 meter of wire so they can run through the radio casing. Its worth taking the time to label all the the wires and positions that they came from as they cannot be re-soldered to the extended wires until all the cables have been fed through the length of the casing, so it virtually impossible to keep track of them all! The volume and tuning extensions must be run through the flexible tube and into the other end of the radio. From here, simply connect the volume dial directly onto the first of the rods, and run the tuning extension through the inside of the hollow support tube and connect it to the second rod.
The speaker must also be extended by 100mm or so, it can be glued to the pre-cut hole. Finally a new battery housing must be added and attached next to the circuit board.