A passive speaker is a speaker that amplifies sound without using electricity.
- To make this passive speaker, this is the list of materials you will need:
- One piece of wood that is greater or equal to 18 inches in length, and one that is greater or equal to 9 inches in length. They should both be 3.5 inches wide, and 0.75 inches thick.
- Two thin pieces of live edge wood.
- 1/4” by 1/3" block of wood
- A handful of sea glass 5 ounces of epoxy resin and the corresponding amount of drops of catalyst, depending on temperature (there is a conversion chart on the back of the epoxy bottle)
- Wood glue
- Provincial 211 Varnish
- A paintbrush
- A cloth
- Blue painters tape
- 2+ Popsicle sticks
Step 1: Tools Table
On this PDF there is a list of tools that you will need, how to use them, and some safety considerations
Step 2: Cut Plans
These are the cut plans you will need to draw on your wood (in a later step). It shows the cut design for each piece and some isometric drawings.
Step 3: Draw the Major Cut Lines on Your Wood
Take one piece of wood, a ruler, and a pencil, and make a mark at 9 inches lengthwise. Then take a speed square and draw a right angle line on that marked spot. Then, draw another right angle line about 1/8 of an inch from the first line. Repeat this first step, but measure the 9 inches starting from the second line.
Repeat this process with your second piece of wood (the second piece of wood will just be one 9" piece, not two).
Step 4: Cut the Pieces Out
Use the miter saw to saw between the 1/8 inch gaps in the lines you drew on your pieces of wood. This should give you three 9" by 3.5" pieces of wood.
Step 5: Draw the Cut Plans on Your Pieces of Wood
Use the cut plans, your ruler, your pencil, and the speed square if needed, to draw the cut plans onto your pieces of wood.
Step 6: Cut Out the Cut Plans You Drew.
What tools I used to do what (All of these tools are explained in the tools table in step 1):
To cut out the top piece of wood, I used the miter saw to cut it into 2 pieces, leaving you with the phone holder piece, and a piece of scrap wood. Then, I used the drill press to make multiple holes in the outlined oval, until it was cut out. It's okay if your cuts are a little bumpy right now because you will sand them later (mine was pretty bumpy).
To cut out the piece of wood that goes under the top piece (the second layer), I drilled a hole with the handheld drill, at each end of the outlined rectangle. Then I took the jigsaw and sawed out all the wood in between. You can leave the rectangle with a round edge (more like an oval), or if you want to make it more rectangular like it is in the plan, you can use the jigsaw to add on corners (this is not essential though).
To cut the third layer piece of wood, for the half where the sound will not be released, I used the handheld drill to drill holes in every corner of the outlined shape. Then I used the jigsaw to saw along the lines of the cut plan and remove the unneeded wood. To cut the half where the sound will be released, I used the band saw to cut along the curved lines of the cut plan.
The bottom piece did not require any cutting.
Step 7: Assemble the Pieces and Sand Small Areas
Prepare for gluing by assembling the pieces of wood to make sure they match up correctly. If they do not match perfectly, you can saw or sand some bits off to make sure they do. I had to use the miter saw to saw off some of the edges my wood pieces to smooth them out and make them all even.
Another thing you should do before gluing is sand small areas with the dremel router tool (with the sandpaper bit). I sanded the inside of the middle piece of wood (#3) and the inside of the top piece (#1).
Step 8: Glue
Glue your pieces of wood together with the wood glue, according to the assembly plan (refer to tools table for directions).
Step 9: Clamp the Pieces of Wood Together
After you finish putting glue in between each piece of wood and assembling the speaker, tightly clamp the wood together, or to a table, to improve the impacts of the glue. Then let the glue dry overnight before continuing to work with your speaker.
Step 10: Sand
Once the wood glue is dry, get the palm sander with 40-60 grift (directions in tools table). Sand all over the speaker until the edges are fairly even and pretty smooth. Then you can take 80-120 grift sandpaper, and sand over your speaker to make it even smoother.
Step 11: Stain the Wood
To stain your wood, get the provincial 211 wood finish, a paintbrush, and a cloth. Dip your paintbrush in the varnish, and paint it on the wood. What I did was after almost every stroke, I ran over it with the cloth, so the varnish wouldn't get too dark, and so it would stay smooth and even.
When you finish, let the varnish dry for at least 8 hours.
Step 12: Put in the Epoxy and Sea Glass
- 2+ Popsicle sticks
- Measuring bottle
- Epoxy resin and catalyst
- Blue tape
- Your speaker
- Sea glass
b.Tape the edges of the speaker so no epoxy can fall down off the sides.
c. Pour 5 ounces of epoxy resin into your measuring bottle. The temperature outside will determine how many drops of catalyst to add into the resin (there is a chart on the back of the bottle that will tell you how much you need). It was 80 degrees Fahrenheit for me, so I read the chart, and it said to put 15 drops per ounce. This multiplied to 75 drops because of the 5 ounces.
d. Put your drops of catalyst into the measuring/mixing bottle, along with the resin.
e. Mix the resin and catalyst quickly but thoroughly.
f. Pour the epoxy-resin mixture into the speaker (in the gap between the thin pieces of live edge wood). Check to make sure nothing is leaking. If some of the mixture is leaking, wipe it off and cover that area with tape so it can't leak anymore.
g. Wait about 15 minutes or until the mixture has gotten thicker, but not too hard that you can't place things in it. Then place pieces of sea glass into the mixture (but not all the way down so they are touching the wood).
h. Let the mixture harden overnight, and once it is fully hardened in the morning, you can remove the tape.