Mechanical Wave Driver for Chladni Plate

Step 5 Mounting Plexiglass, Testing

Place a 3/8 X .171 X 1" nylon spacer in the hole in the middle of the plexiglass. Mine holds just fine with compression but you may need to use a little superglue. With the standoffs and spacers mounted on the outer rim of speaker, gently place the plexiglass disc over the threaded rod. It should slide comfortably over in the nylon spacer. Make sure the rod is sitting straight! Press gently down on the cardboard to make sure the rod can move thru the nylon guide. Mark your screw holes on the disc above the standoffs then remove to drill out. I would drill one hole at a time then put the disc back on to be sure of alignment. After all holes are drilled, screw plexiglass into place. Put just a small dab of oil where rod slides thru nylon guide.
Now would be a good time to test on a Function Generator with an amplifier. I use an old 30W amp but will probably make a smaller one for the science fair.
The rod should vibrate freely in the guide.