I'd try Molybdenum Disulfide powder.
Funny story about Molybdenum Disulfide.
Most of a lifetime ago, I was in Cub Scouts and the annual Pinewood Derby was coming up. I’d already done the ‘raise one wheel’ and 'center the weight' tricks, but felt I needed something more.
My father was an engineer and was at that time, designing a stabilization device for a centrifuge in the event the main shaft broke. The device was essentially an external drum brake, but to ensure limited negative inertial damping and heat on the rotor, the shoes of the brake had Molybdenum Disulfide baked into the contact surface.
My solution for the pinewood derby car was to, after polishing the nails used for axles, heat them, and try to impregnate the MoS into the surface.
Long story short, it worked and I won the event, by a wide margin. I also competed and won the regional and state gatherings. Each time, my car was inspected before the event and was certified for use. Being a young egomaniac, I didn’t keep my secrets to myself and blabbed (bragged) about the improvements.
One of the dads at the regional event, a lawyer, sent a formal complaint to the BSA governing group, accusing me of violating the rule (at the time) that the car must be made 100% by the scout without adult help. He argued an 8 year-old was incapable of conceiving the technical aspects of the improvements, and that my father must have helped.
3 months later, the B.S.A. head legal counsel decided I had broken the rules and vacated the wins. Needless to say, I was pissed and the incident effectively ended my involvement with the scouts.
Fast forward 24 years…standing in a church in Boston, as a groomsman in my kid sister’s wedding. Being the tallest of the groomsmen, I was situated next to the best man, the groom’s father . . . who was in fact, the (retired) head legal counsel for the Boy Scouts of America who made the decision against me.
