(Polishing) Using Water
Adding water increases the abrasive abilities but at the same time reduces lubrication by displacing some of the lubricating oils. Very similar result are obtained when your wet-sanding; the more surface water the less the abrasive the finishing paper becomes.
Separation of oil and water is caused by a tension in the surface between dissimilar liquids. As water (or a water - oil emulsion) for all intents and purposes is incompressible, so that the pad and the abrasive don’t have actual surface contact, due to the pad hydroplaning.
When this condition is encountered a layer of water builds up between the surface and the abrasive, thereby negatively impacting the abrasive abilities of the polishing process, unless this water is displaced from the surface and the pad via centrifugal force, because the pad cannot in effect "squeegee" the water from the surface.
Adding distilled water or 1:1 solution of distilled water / Meguiar’s® M34 Final Inspection keeps the working area wet by misting the surface. Be cautious as spraying excess water can cause the foam pads to aquaplane
Once the polish starts to vaporize (flash) its abrasive ability will drop of to zero, but instead of adding more polish, which will form a semi-solid between the pad and the paint surface, this hardened residue will scour the paint surface.
Using a mist of distilled water while compounding helps; not just for pad / surface cooling, but it can increase the abrasive ability by keeping the pad surface clean and re-liquefying the polish enabling the pad to work the way it was designed to. allowing you to use the polish efficiently before more is needed, it also creates less dust, avoids fibre twisting (wool or microfibre) and positions them more closely together, which increasing their levelling ability.
Although this helps to clean the pads cutting surface it doesn’t take the place of a freshly cleaned pad, it’s very important to periodically replace the working pad for a clean and primed pad.
Water is similarly used when sharpening knives on a stone, this helps to keep the blade cool and at the same provides a lubricant, which improves the abrasive ability of the stone and it also helps by removing abraded debris from the blade edge. I also add mineral oil to the stone to lessen surface resistance and to improve lubrication.
Most quick detailer or pad conditioners are usually formulated with silicones, oils, waxes, polymers or gloss enhancers, which will negatively affect the polish abrasive abilities (an exception is Meguiar’s® Last Touch Detail Spray diluted 1:1 distilled water) (See also Foam Pad Priming)
Polishing pads can "load-up" with residues, especially when polishes or compounds become saturated, thus reducing their effectiveness; you should always be able to see the pores of the pad. It’s always advisable to clean and/or replace pads as necessary
a) Rotary - using a spritz of water will increase the abrasive ability of a pad / polish combination and; the centrifugal inertia created by the machine would help to return the abrasive to the paint surface. If the pad is not kept clean (especially when using a water spritz), the abrasives and oxidized paint residue tend to accumulate onto the pads membrane structure, and stay there; this does not work with all compounds.
b) Random orbital - it’s not generally recommend implementing this with a random orbital unless this water is displaced from the surface and the pad via centrifugal force. The main reason for this is typically, a lack of centrifugal motion, because there is less high speed rotation of the pad, so the residues tend to stay where they are compared to using the same setup with a rotary(Based upon methodologies suggested by Kevin Brown)
