This is one on old designs I made as an attempt to build e-drum pad for kick pedal. The construction is based on 20mm pvc tubes. You also need some mesh material for the head; I used mosquito mesh from nearest store, where i bought also the tube.

Assembly: I used double side tape to attach 35mm piezo sensor into the frame. The cone is made of standard packaging foam, quite rough. Hardest part is to put on the mesh. Idea is following: First with a zip tie you need to fix the mesh in place (see illustration). You need to maximize the tension at this point. Then the hot glue will help securing the mesh and hide all the loose ends. After that, few rubber bands will help create needed tension and also work as vibration dumpers.

I used this design for half a year until i finally moved on to more classical mesh design (see https://www.thingiverse.com/thing:4296480 for details)