How concerned are you about scuffs marks and scratches on you porcelain?.....especially yellow insulators that highlight ever scratch and scuff like it was neon......If your glaze is relatively undamaged, you can polish away those scuffs and scratches made by wire. Weiman metal polish is especially effective with removing friction stir like weld marks of aluminum, and to a lesser extent marks made by copper and black insulating wrap. You can also just shine up a dull glaze by breaking through its surface scum. After polishing the chrome parts on my snowmobile one night I got this crazy idea to try Weiman metal polish on a yellow insulator I had recently purchased, and low and behold it worked like magic....I'm not going to lie to you though, this method also requires a little elbow grease, which does not come in a bottle yet.

ALSO....I am not a paid spokesman for Weiman metal polish, nor am I responsible for any damage caused by this product.

Seeing is believing, so I have provide some before and after pictures....This insulator had both aluminum and copper wire scratches and black friction marks from rubber insulation.

http://insulators.info/pictures/?id=385324794

Polishing Glass.......I have also has some limited success using this polish to remove rust marks from glass wire grooves