What material should be used to fill gaps exceeding 1/4 inch on two sidewall tubes?

Using ceramic fiber rope to fill gaps exceeding 1/4 inch on two sidewall tubes is appropriate due to its high resistance to heat and thermal shock. Ceramic fiber rope is designed to withstand extreme temperatures, which makes it suitable for applications in boilers, furnaces, and other high-heat environments. Its flexible and compressible nature allows it to seal larger gaps effectively while preventing heat loss and maintaining insulation integrity.

Other materials, such as cement or clay, may not provide the necessary flexibility or thermal resistance for applications involving high temperatures. Insulation tape is generally best for smaller gaps and wouldn’t be effective at bridging larger spaces as required in this scenario. Thus, the properties of ceramic fiber rope align perfectly with the demands of filling larger gaps in high-heat areas, making it the correct choice.