How to Clean up faded speaker cones

[colin.hepburn]

Hi all
Has anyone got any ideas on what to use to brighten up faded speaker cones I have my Wharfedale 6.5in Kevlar drivers and my Fostex 126Es

The Fostex 126 cones are aging and fading back to banana yellow from the bright white they were when new I would like to get them back to the white again any ideas on what I could use on them that will not damage the drivers



And the yellow 6.5 inch Wharfedale Kevlar Drivers. where a victim of chip pan oil smoke some years back which would not clean off I was thinking of dying them black so thought about maybe using black printer ink which I have on hand

Any other ideas would be very welcome
Thanks
Colin