Introduction: Frame Drum Bendir Extension Kit

A frame drum is by definition a drum that has a drumhead width greater than its depth. It is my big love: Frame drums produce an enjoyable sound with many nuances and subtleties to listen to. Moreover they offer a wide range of possibilities to alter, change, “play” with the sound. Simply different playing positions – whether sitting and squeezing the drum between your knees, or standing and carefully holding it with your hands – do make a difference on the sound. The sound can be further varied but hitting the drum in different ways and on different spots, on the head, the frame, the head and the frame, with your fingers, nails, knuckles or your whole hand. All in all, frame drums are said to be one of the most ancient musical instruments in the world, and could be found across many cultures.

The bendir is a special type of frame drum originating from Northern Africa and the Maghreb. It is a frame drum that has a built-in snare system, which adds a rattling, buzzing sound quality to the original frame drum sound and makes the overall sound even more complex. The snare system consists usually of two or more tensioned cords which are in direct contact with the drum head. Sometimes the cords do also carry beads, that make the buzzing sound louder and more prominent.

However high quality frame drums and bendirs cost a fortune. So what should one do if he or she has already spent all their money on a quality frame drum, a 3D printer, and still wants to enjoy playing a bendir? Right! We will build our own bendir extension kit for a normal, bare bone frame drum! And the big advantage of this is: You can even disable the snare system during playing by moving one of the holding clamps up on the drum’s frame so that the snares do not longer touch the drum head.

All in all, we just need:

  • A quality frame drum
  • 3 3D-printed parts: the top clamp, the bottom clamp, and the bottom clamp’s slider for tensioning the snares
  • 2.2m of nylon cord as snares (I have used a 0.4mm cord, but thicker cords up to 2mm are also possible)
  • 1 M4 40mm screw (no countersunk head; either slot, cross slot or hex socket)
  • 1 M4 locknut with nylon collar
  • Optional: Beads fitting on the nylon cord
  • Optional: A shortened nail with a big but flat head (e.g. roofing nail, drawing pin etc.)

Step 1: Printing the Parts

The following instructions presume a 22” Remo frame drum with Renaissance head. If you have a drum with different dimensions, you need to adjust the attached Fusion360-CAD-file first (BendirExtensionKitV4.f3d).

Start with printing the top clamp (MountingTop.stl). It is important to print it in a lying position due to the force that will be later applied to the part by clamping and tensioning the snare system. The part needs to be printed with support material. To improve bed adhesion especially when printing with ABS, it is also important to add a brim. Cura slicer settings: infill “50%”, infill type “grid”, wall line count “3” (i.e. print it with 3 outer walls).

With my printer, I had quite a hard time removing the support material from the long and small holes for the cords. Therefore, I recommend to delete the support material from these holes before printing the part, see the Cura forum for more details on how to use the so called “Support blocker” tool. All in all, the long holes for the cords can be printed without any support material without any problems.

Next print the bottom clamp (MountingBottom.stl). For the bottom clamp applies the same as for the top clamp: Print it in a lying position with supports and a brim. Again: Infill “50%”, infill type “grid”, wall line count “3”, support blocker enabled for the cord holes.

Last print the slider (MountingBottomSlider.stl) in a standing position. It needs supports and a brim, too. Infill “25%” is enough, though.

Finally check the printed parts and get rid off any sharp edges and corners especially in the area where the clamps meet the drum head. For this task, I usually use a needle file on which I have fixed a piece of 120 grit sand paper using double-sided adhesive tape.

Now test the clamps by putting them on the drum and carefully pushing them down into position. Make sure that you do not punch through the drum head! If the clamp is too long, add some tape on the inside of the clamp to make it sit higher. If the clamp is too short, you might need to remove some material. But for the above mentioned 22” Remo drum, it should be just fine: There is no need to adjust anything. All in all, between the clamp and the drum head, there should be just enough space for the nylon cord you intend to use, i. e. the snare fixed to the clamp should touch the drum head.

Step 2: Preparing the Printed Parts

Next take the slider and put in the locknut. The hole for the nut is designed for a “press fit”, so it might be quite hard to get the nut in. Use a knife to make a small chamfer, and get the nut into position. Now the brute force part: Take a hammer and drive it in! Done? Assemble the screw as the last step.

Optional (so as to reduce the wear of the bottom clamp when tensioning the snares): Shorten a 1.6mm roofing nail to a length of about 5mm. Use some pliers to press the nail into position. Protect the printed part from being scratched by the pliers with a towel.

Step 3: Assembly and Mounting

We are now ready for the assembly. As shown in the images above, insert the nylon cord in the left hole of the top clamp first. Since my cord is a 0.4mm cord, I used a bead as a stopper before placing the knot on the cord.

Now run the cord from the top clamp to the left hole of the bottom clamp. Change the direction and run the cord through the middle hole of the bottom clamp back to the middle hole of the top clamp. Again change direction and run the cord from the right hole of the top clamp back to the right hole of the bottom clamp.

Next mount the clamps on the drum. Make sure that you put the clamps on the drum in such as way that they are directly opposite of each other and that the cords do run through the centre of the dream head, i.e. the cords should meet the clamps in a 90 degree angle.

Tension the cord with your fingers and make a first sound check. You can make the buzzing sound more prominent by putting some beads on the cord.

Happy now? Take a pen and mark the spot where the cord leaves the slider. Unmount the bottom clamp, put a bead on the cord as a stopper and put a knot exactly on the marked sport. Now remount the clamp and tension the snares with a screw driver / hex key. If you have put beads on the snares: Use some tape as stoppers to prevent the beads from travelling all over the snares when playing.

Step 4: Enjoy!

We are done! Enjoy playing your new bendir! And by the way: If you found this instructable inspiring and life-enhancing for you, you can also buy me a coffee :-).