Making Two Okedo Drums
A project by:
Gabriel B. Soares
Summer 2010 - Spring 2011
As I have described in my "About" page, in the fall semester of freshman year at Cornell I joined a Taiko (Japanese Drumming) group called Yamatai, which is where I was first introduced to this new style of drumming and art form. One of the things that drew me into the group was the fact that it was self-run and we had complete control over the direction we wanted the group to go in. However, one of the main difficulties that we faced, and as far I know this is a difficulty all North American Taiko groups have, is getting enough funding to buy these incredibly expensive drums (a couple thousand dollars per drum)...
Due to the inaccessible cost of most of these, groups have been getting increasingly creative and finding new ways to build their practice drums. I have seen drums made out of old tires and duct tape, out of large plastic trash cans, large PVC pipes, wine barrels, etc. Given my love for woodworking and drumming, I decided to give it a shot and build two Okedo drums which I would then donate to the group. This page therefore describes the build process for these two drums: one made out of maple and the other out of red oak.
There were a few constraints going into this project which dictated what I could and could not do.
The first of these was of course cost! As a poor college student paying for all the materials out of pocket, I had to make sure that I didn't try to tackle a project which I wouldn't be able to complete due to lack of funding. This meant choosing materials that are easy to find, fairly cheap, and of good quality. My choices for wood were quickly limited to maple and red oak. These are the easiest woods to find, are fairly inexpensive, and very easy to work with (the all-stars of wood species). I wanted to try to build one drum out of each species to see what effect the wood density would have on the sound.
The second constraint was drum size and construction method. I was using my dad's wood shop which did not have a lathe. This meant that I was limited to building the body of the drums using staves. With a stave construction you end up having to make a tradeoff between the number of staves-per-drum and hours-spent-sanding. The higher the number of staves, the easier it would be to achieve a rounded body, but would take longer to build and make the drum potentially less sturdy. Given the size I wanted to have the final drums (18" diameter; 24" height), I found using 28 staves (2" by 3/4") would allow me to get to a fairly rounded shape and reduce the amount of time spent sanding.
I began this project by drawing out the shape of the drum and calculated the angles I would have to cut each side of the staves in order to get a circular body. Drawing it out also helped me make sure that I was getting enough material to complete the project and have a reference to look back at to make sure I didn't make any mistakes.
I then went to a flooring lumber yard and bought all the material I was going to need. I found that these specialized lumber yards carry higher quality woods than you would get from Home Depot or Lowes (sometimes at cheaper prices too). Once I had all the measurements and materials, it was time to do some test cuts and begin building some jigs.
I began by testing the angle of the table saw blade on a small sample of the maple wood and by building a jig to use on the drill press to make sure that everything was ok before starting any work on the long final pieces. I made small adjustments based on the results on the test pieces which allowed me to be more confident once I decided to go into production mode. With 28 pieces per drum * 2 drum + slop (about 60 total pieces), building a jig allowed me to get consistent results and get through all the cuts much faster.
I began all my cuts on the maple wood since its a softer wood and would be less taxing on the blades. The first image below shows the maple staves after having their sides cut at an angle and cut to length. I then took all the pieces to the drill press and drilled three holes on each side for dowels (if I were to redo this I would probably use biscuits instead but I didn't own a biscuit joiner at the time). After doing all the maple pieces I noticed that I probably didn't need three dowels per side and decided to use only two dowels for the oak pieces.
Assembling The Maple Drum:
The assembly process is fairly straightforward. It consisted of lots of glue, lots of dowels, and lots of clamping force. The only difficult part was putting the pieces together due to the fact that any slight misalignment with one of the three dowel holes made it tough to bring the two pieces together. This is where the rubber mallet came very handy. The two first images below show the before and after photos for putting the maple drum together. I used a ratcheting strap to clamp all the pieces together while the glue set. I found that using two straps wasn't quite enough and would have been better had I used another strap in the middle of the body.
Once the glue dried, I inspected the drum and found a few small gaps between some staves which I didn't like. Any significant gap between the staves would certainly affect the sound of the drum since it would allow air to escape and enter the inside of the drum as the head is being hit. To solve this I build a small "glue bath" for the drum that allowed me to submerge parts of the drum, which I rotated every 15 minutes. This allowed the glue to enter and fill all the voids. Although this method worked well for sealing the gaps, it also added a thin film of glue around the wood which made it harder to sand...
Assembling The Oak Drum:
The oak drum was easier to assemble than the maple because I had learned a few things in the process. Instead of three dowels, I used only two (the strength of the joints came from the glue and the dowels were used just to align the pieces correctly), and I didn't end up with any noticeable gap between the staves. I also used four heavier-duty straps to clamp the whole thing together (this really helped close any gap).
In the images below you can see the assembly of the oak drum as the maple drum is drying.
Cutting to Length:
As you might have noticed in the previous images, once assembled, the two drums were of slightly different heights. At this point I had to cut the edges so that their heights would match. I did this by simply establishing a straights edge and cutting the edge with the jigsaw.
Routing the Edges:
I decided to route the edges of the drum with a 45° angle on the inner edge, and a rounded outer edge. I did this in order to reduce the amount of surface area that the head of the drum would be in contact with the body (to help minimize rattling). So for this I took out the routing table, installed the 45° bit, and slowly worked on the inner edge on both the maple and oak drums.
I then switched to a 1/4" rounded bit and worked on the outer edge.
Sanding and Painting:
Now came the fun part (*read in sarcastic tone*): sanding! This took multiple days and more sheets of sandpaper than I could keep track of. I started with a very low grit sandpaper to try to bring the drum as close as possible to a cylinder, and then started moving towards higher grit until everything was nice and smooth (the maple gave me the most trouble since it had a thin coat of glue I had to get through before I could get to the wood). The hard work paid off in the end; I was very happy with how the drums were starting to come out (see first image below).
The next step was to figure out what color I wanted to paint them. I tested a few different colors on scrap pieces of oak and maple to see the kinds of results I could get from stains and polyurethanes (see second image below). I ended up picking a Cherry stain for the maple drum, and a clear polyurethane coating for the oak drum (I loved the grain pattern on the oak drum and wanted to preserve it). It took a few days and multiple coats to get the end result. On the maple drum, I also added a few coats of the clear polyurethane on top of the stain.
Making the Heads:
I'm going to go through this section quickly because the process is the same as making a Shime Head which I covered in another project writeup. Essentially the first thing I had to do was purchase metal rings large enough for the heads (I purchased 24" diameter rings), and apply a primer to the steel rings so that they don't rust over time.
On a piece of paper, I then drew the stringing pattern that I was going to use to skin the cowhide over the ring. As you can see, this pattern consists of 36 holes around the perimeter of hide. The formula I used for the stringing pattern is: ((n + 11) mod 36), where n is the current hole number and starts at 1. This creates a stringing pattern that goes: 1, 12, 23, 34, 9, 20, 31, 6, 17, 28, 3, 14, 25, 36, 11, 22, 33, 8, 19, 30, 5, 16, 27, 2, 13, 24, 35, 10, 21, 32, 7, 18, 29, 4, 15, 26. If you are interested in the math behind this sequence I recommend you look into Cyclic Groups.
With the rawhide tensioned on the ring, the next step was to stitch the hide with sinew in order to hold everything together. Once the head has been stitched, I removed the nylon string that was holding the tension.
The last steps were to cut the holes for the rope to pass through and tension the head onto the body of the drum so that it would dry conforming to the shape of the drum.
Painting the Heads:
For the maple drum I decided to try to paint the heads with a black lacquer paint which I thought would look nice with the dark Cherry body color. I chose a car lacquer paint since it would be very durable and would not easily come off from being hit with a drum stick. I began by drawing the Mitsudomoe pattern on one of the heads. I then spray painted with the same lacquer paint the surface of the head that is not played on (edges and underside).
This project took a while to complete but I had so much fun building the drums that I think it was worth the full three-month effort. I learned a great deal in the process and feel a lot more confident tackling this sort of project in the future. With my membership at the Techshop I am already thinking of making a few more drums, but this time using the CNC machine and lathe.
I ended up donating the maple drum to Yamatai. I am very happy that the group has been using it frequently for its performances (they even have a name for it: Gabedon). The image below shows the drum on stage at Bailey Hall during the annual performance on my senior year.