The one criteria I set for this was to use only things I have on had (except for the sand and dowels for the rake since I knew I needed specific things for those that I didn't have).
Step 1: Tools and materials.
Step 2: Marking the wood for the yin and yang
Step 3: Cutting to shape
Step 4: Building the rake
Step 5: Putting it all together
Step 1: Tools and Materials.
Clamp with scrap wood
Drill with 3/16" wood bit
1" thick wood (It is best to use a solid piece of wood instead of some sort of ply wood
since you will see the sides)
Dowels, 3/16" and 1/2" thick
White and black sand (I pick some up at my local arts and crafts store, you could also find
it at a fish shop or Petco)
Step 2: Marking the Wood for the Yin-yang
This is the most important part of the instrucable. You need to make sure everything is labeled exactly as it should be. We will be marking a 7" circle which will be the overall shape of the Yin-Yang. There will be 1/4" barrier between the two sides and 1/8" barrier in the smaller circles.
Everything needs to be marked out before you cut anything. I cut the circle first and because of that I had to screw the yin and yang to my work table from the bottom.
Mark the circles in this order
7" main circle (image 1 then image 2 is when I cut out this circle, DO NOT cut it yet)
6 1/2" inner circle (image 3) make sure you use the same center point as the first cirlce
(pictures 1, 2 and 3)
To mark the next circle you will need to take your ruler and measure the mid point between the center of the first two circles and the edge of the 6 1/2" circle. This should be 1 5/8".
Using that point draw your next two circles with radius of:
1 5/8" and 1 3/8"
(refer to the horizontal notes on the left side of the picture 4)
Repeat for the other side
At this point you should see a figure 8.
Now you will need to create the two small circles that will hold the black sand on the white side and white sand on the black side.
You will do this the same way you made the last two circles except smaller and different center point.
Since you already have the center of the last two circles you will need to measure the mid point from that to the edge of the 2 3/4" diameter circle. I eyeballed it for mine (prob not such a good idea but it looks fine to me) but you should make sure when you mark the center point for the new circles you make it a 90 degree angle from line A in the pic (on the right side of picture 4). On the left make sure this circle is above line A and on the right it must be below line A.
(Line A is from the center of the 7" circle through the center of 2 3/4" circle.)
Using this new center point draw out two circles with radius of:
11/16" and 9/16"
(refer to the notes of the right side of picture 4)
Repeat for the other side.
There are three places you will need to mark freehand, the center where the medium circles connect and the two edges where those two circles connect to the 6 1/2" circle. (These are marked 1,2 and 3 in picture 4 in the vertical notes.)
After all the circles were marked out I colored in the areas to be cut out with the router. I used the pencil I had but you may want to use a marker or something a little darker since it will be cut out anyway, but make sure if you use a marker to stay within the lines you plan on cutting out.
Picture 5 is marked with a whole bunch of notes showing the area that was going to be left alone since the picture I took didn't show it so clearly.
Step 3: Cutting to Shape
I made two passes while routing it out. The first was 1/4" deep and the second making it 1/2" deep. Be very careful not to cut outside your lines. Go slow and steadily. Make sure you wear eye protection for this. On the first pass I left between 1/8" to 1/16" between the router and the lines. The second pass I got as close as I could but not going all the way to the lines.
Once you finish routing you should end up with something like the picture below.
Next you need to sand the edges to as smooth as you can trying to sand up to the lines creating the yin and yang.
Now you can put whatever kind of finish you want on it. I sprayed clear polyurethane with a satin finish then sanded down the top. I felt it gave a nice worn in look to it. You can see the lines aren't perfect but when the sand is in it you don't notice it much.
Step 4: Building the Rake
I took the 3/16" dowel and cut a piece about 6" and stuck it through the hole the goes all the way through the 1/2" dowel.
I then cut 2 small pieces of the 3/16" dowel about 3/4" long and stuck each one inside the holes and sanded them down making them the same length.