How to make the sanding discs for my random orbital sander sticky again??

For PAR: Mirka has protective pads that protect the hooks of the sanding pad. Then at least you are not ruining your pad, just your pad saver.

 

for years we would squirt laq thinner on the pad whipe it then squirt again and light it on fire it burns clean and helps.....if the disks are bad stick it on pad while moist with solvent. light it out side dont blow your self up or burn your self