You can, of course, brush them, however this will not last long. More radical means of plastic washer embedded between the half-loops.
There is another way to get rid of the squeak. You need to shorten rod one half loop and put the loop inside a steel bearing ball.
Recommend to read
EVEN ON “FRANTIC”
In our magazine in 1973 (No. 2 cover No. 3, 4, and 6 — description and recommendations) we talked about the boat "TFA" air cushion, created by Swedish designer, Amateur Cumbersom...
GLIDES… CAR
Curious glances accompany this crew everywhere. And it’s not surprising - it looks too unusual in the traffic... a boat on wheels. We are talking about a vehicle that exists so far in a...
