Step 1: Materials list
. 1 working radio chip and speaker
. arox 1sq M of fiberglass matting
. arox 500ml of fiberglass resin
. arox 10 ml of fiberglass hardener
. 1 new bathroom plunger
. 1 tub of car body filler and hardener
. 3 small pieces of wood
. 2 small pieces of 3 mm pvc plastic
. 1 old bike inner tube
. 3 small nuts and bolts ( size is optional)
. 1 hot melt glue stick
. 1 can of gloss spray paint
These are the materials i use but many can be substituted with alternate build methods.
Step 2: Exploded Diagram
Step 3: Dismantelling the radio
Step 4: Building the Outer casing
Step one is the making of the impact resistant and waterproof outer shell. The things you will need are
1. A well ventilated space either outside or in a large room. This stuff smells pretty bad and the smell will hang around for a few days if you do it in your house. I did it in my new shed hence the reason for all the electrical wiring that is exposed in many of the photos.
2. A piece of cardboard.
3. A cone shaped mould.
4. A flat surface
9. An old brush
10. A pair of scissors.
11. An old container.
12. A dust mask
13. latex gloves ( i was already wearing mine)
Once you have gathered up all these materials you are ready to get started. Start off by putting on your gloves and dust mask. Next put down your cardboard so prevent any spillage that may happen wrecking the work top. Take the cones mould and line it with two layers of cling-film. This will stop the resin sticking to your mould. Next cut up the fiberglass matting into a manageable size. Place one layer of the the matting into the mould. I found if you cut up the middle of the square it made it easier to place the matting in to the mould. Once the whole mould is covered it is time for the resin. Get a flat bottomed container that is disposable and mix in 1 part hardener to 50 parts resin. So I found about 2 ml of hardener with 100 ml of resin was about enough for this project. mix it well as if it is not mixed properly the reaction can not happen and the resin will not cure. With the old paint brush begin applying the resin to the matting. Apply generously and make sure the matting is soaked through. There should be no dry spots. Repeat this process another 2 times so you end up with 3 layers of matting completely covering the mould. The resin will begin to set after about 15 minutes so you have to work relatively quickly. With the left over resin and matting on a flat surface make a disk shape. that is bigger than the base of the cone. make this about 3 layers thick also. After around 20 minutes the resin should be almost set and because of the chemical reaction it should become hot. Just before the resin sets completely take the cone out of the mould and peal off the cling-film then allow it to set completely. You should end up with a perfect cone and a rough disk shape. Both can be trimmed roughly at this stage with a pair of scissors. I should add that if you are working with fiberglass at colder temperatures then you may need to apply heat or add more hardener to make the resin harden. You have completed stage 2!
Here is a link to where i got my fiberglass. It is available in many places online.
Step 5: Fitting the suction pad
I moved from my shed at home into the University workshop for the next stage. Many may not have some of the tools or these kind of facilities available to them but you should be able to make do.
I cut out the disk into a perfect circle using the ban saw and a disk sander. I had made a paper template to see what size of disk i would need to still be able to fit in all my electronics. Next i had to fit the plunger to the bottom of the disk. I bought this plunger from B&Q for £3. It has a thread on the base which made it ideal. I drilled a whole large enough for the thread to fit through so i could screw on the plunger from the other side and it would sandwich the fiberglass disk. I then cut off the excess handle and gave it a quick sand for neatness.
Step 6: Trimming the shell to the correct size
Next I marked where the disk would sit on the inside of the cone. This allowed me to cut off the excess around the bottom. I cut it with a hack saw on top of an extraction bench because the dust is very toxic. Wear a dust mask for this stage. I cut the bottom in a wavy pattern to make it look more shell like and gave it a sand to get rid of any splinters.
Step 7: Making fixings to hold the case together
Next i made this fixing that will hold the bottom disk onto the cone. To do this i cut out 4 pieces of wood that had one face that is at the same angle as the slope of the cone and one face that can sit on the bottom face. This took some fiddling about to get the correct angle and to get them lined up properly. I used more fiberglass and resin to fix the three pieces of wood to the cone. the fiberglass sticks really well to the wood so it gives a nice strong fixing. In the drilled hole i counter sunk bolts that were a tight fit. this meant that the bolt could be tightened from the bottom plate. I drilled 3 holes on the bottom plate for the bolts to pas through.
Step 8: Making the seal
Step 9: Creating the shell like texture
Step 10: Adding the contolls
Step 11: Painting
Thanks very much for looking at my Instrucable and I hope you will have as much fun making it as i had designing and building it.
any comments or feedback would be much appreciated and if you have any alternate ways you built the radio wave then let me know