Custom Snare Drum

Building a stave snare drum shell and pouring sand cast zinc lugs

^You can watch this 4 minute video, v or read this 4 minute writeup

(or both)

In Spring of 2019, I scratch-built a custom 13.5" maple snare drum for my Design for Manufacturing term project. The shell was cut from a single maple board such that the grain pattern continuously wraps around. The lugs were designed on Solidworks and sand cast using a DIY green sand mixture and 3D printed positives.

This is a quick and dirty, high-level writeup of my DFM project!

The Process

A stave drum is built by first making a rough polygon-y cylinder (called a stave), then rounding down to a proper looking drum shell. I started by figuring out the length and thickness of board I would need to build the stave. There a few considerations here. The more segments you have, the thinner your board can be and the less material you will have to remove, as the polygon will better approximate the end shell. However, it becomes increasingly difficult to control your angle tolerances.

Most of these pictures are from an unfinished build I attempted with a 24 segment stave. The shell I eventually finished was built with 16 staves. I would highly recommend biting the higher cost of thicker wood and using fewer segments!

Cutting the Staves

After cutting the board into segments, I used a router to cut the angles. Each segment was numbered to preserve the grain flow. I slightly oversized each segment since there's no coming back from cutting too short. After they were all cut, I used a belt to hold the staves together in a mockup to measure the diameter across. This allowed me to figure out how much material to take off of each stave. The width of each stave could be fine tuned with a routing jig that allowed me to remove a playing card's worth of material per pass.

Gluing

With the staves finished, the next step is to glue them together. This can be a messy and very tricky process. A great trick I learned from a stave building forum is to lay out the segments wide side-up, edge to edge. Tape them together from the top (wide) face with continuous strips from end to end. From here you should be able to roll them up easily with the tape holding everything together from the outside. Flip it over tape side down (gaps facing up) and the gaps can easily be filled with glue and rolled up.

The final step is to tightly bind the snare drum with hose clamps to keep pressure on the joints as the glue dries. This helps squeeze out the bubbles, maintain tight joints and allows the glue to cure to maximum strength.

Ironically, none of these photos show gluing happening, but this helps with the overall picture

Rounding the Stave

The next challenge is turning this polygon-y cylinder into a smooth, round drum shell. There are many ways to do this and most involve using a router. I designed a jig that could be reconfigured for different sizes of drums. My jig requires two perfectly round "wheels" to sandwich the staves. The wheels clamp onto the shell and are held in my jig by 4 bearing on each side. This allows the shell to rotate smoothly under a router tool.

The jig is first used to round the outside of the staves with the router sled on top. After the staves are rounded, the wheels can be removed and the jig can be flipped over and set up to round the inside of the staves.

Rounding jig setup. I had a lot of luck with this design!

^Cutting the wheels and building the jig v Rounding the shell

Once the shell is rounded and made as thin as desired, the last step is to route the edges perfectly flat then add a bevel/corner for the drum head to sit on. This is one of the most critical aspects to a snare drum's sound, so be sure to do your research before this part!

Casting the lugs

For this build, I chose to manufacture the lugs myself for the added challenge and to take the customization up a notch. Models for the lugs were designed on Solidworks and 3D printed. They have a slight draft to aid in mold removal. I used a DIY mixture of greensand which consists of silica sand and bentonite clay.

I chose to use zinc as its low melting temp makes it easy to sandcast. It can be melted over an electric stove top burner without the need to fire up my coal smelter. After cooling, the lugs needed some final shaping. I milled out a hollow cavity and drilled holes to accommodate the mounting hardware.

Definitely do NOT melt pennies stamped after 1982 for a cheap zinc source below market value! That would be defacing federal property and very bad!

Finishing Details

The last step is to put it all together! I ended up cannibalizing a lot of hardware off another snare drum like tension rods, rims, snare wires, and the throw-off. Unfortunately, I didn't stain or finish the outside since I ended up assembling the drum around 11pm the night it was due. I went to my buddy's house and set up my drum set with the custom snare. He was chill enough to let me bust out some quick chops for my presentation video, and I spent the rest of the night til dawn in the campus library making my project video.

If you enjoyed this quick read, check out my flute controlled robot or DIY jet engine!

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