Graf-Ex is a special purpose coating stripper designed for safety and low odor. It is an outstanding performer in the removal of inks and paints from painted surfaces. Water can be used to stop its penetration and to rinse. Graf-Ex is not dilutable. Use it straight and apply with either a low pressure spray or wipe it with a cloth and rinse.
AcrylicStrip, Stripper Cream, or LCS will remove most graffiti. AcrylicStrip is a solvent based stripper, good on a wide variety of paints, but safe for the environment. LCS is a thin water based product that should be sprayed or agitated, then pressure washer rinsed. LCS is caustic based. Stripper Cream is a paste used for multi layered graffiti and tags. It is caustic based and requires time for complete removal.
Stripper Cream is recommended for the removal of graffiti on limestone because it will not change the color of the stone or damage its structural quality. First, pre-wet the wall with a pressure washer. The product may be rolled or brushed on to help it to be pushed into the interstitial pores of the stone. For large areas, spraying would be beneficial.
Spray with PlexiClean, undiluted, allow product to dwell for 5-10 minutes. Then wipe or pressure wash off. Note the ingredients in the High Temperature paint melted the plexiglass.