Spinning wheel - Double Treadle wheel clicks while treadling

This applies to all DT wheels

Question:

I have a double-treadle, and it makes a clicking noise when the right treadle goes down. It's taken me a while to figure out the source of the noise, but I finally saw that was the double-treadle assembly. As the right treadle goes down, the piece of wood that connects the two treadles slides on the metal rod. It goes in the direction of the back of the wheel and makes a click when it does so. In the photo you can see that the little plastic bearing has been repeatedly pushed until it protrudes slightly on one side (the one facing the front of the wheel) than the other. I used a thin screwdriver to center the plastic bearing, but it doesn't make any difference. When the right treadle depresses, the click happens again.

Answer:

I have seen this clicking before and while you have identified where the sound is coming from, I’d like you to look at the flexible connectors on each side of the rocker arm.  While they are flexible, they do have a stiffness in the polyurethane.  I have found that after so much repetitive motion, the polyurethane connector loses its integrity and can bend.  As you treadle it bends when it shouldn’t which actually creates a “snapping” and the rocker arm has enough play to move quickly, in the snap, and create the clicking sound.

If you inspect the polyurethane connectors to see if they are deteriorating - replacing one or both will likely eliminate the sound (part number SR0112)