Once you're done with the lamination and the hot-coating steps of the process, you will need to sand the board to give a perfectly smooth finish.
In this step of the process you will require the use of a rotating sanding machine hand-held with disks (ranging from 600 to 2000 rpm), allowing to use lower speeds for sanding or polishing, and higher speeds for lustring the board. The Milwaukee AP12QE sander is perfect for these duties, widely used in the professional surfboard making workshops around the World. Close to 1kg lighter than any of its competitors, it is the perfect tool combine comfort of use and precision work.
You will need to be constantly moving the sanding machine on the board to avoid the overheating of the fiber and the resin by disks. Otherwise, this over-heating will result into a permanent yellowish stain.
In order to facilitate the sanding process, sanding pads/disks of various diameters and densities are available, to address each step of this touchy process.
Therefore, for the beginning stage of the sanding, a larger and harder pad (8" - 200mm) on the plane areas of the board, and a smaller and softer or super-soft (6" - 150mm) for the precision work on the curves and rails of the board, to keep the actual shapes/curves of the board.
The first step of the process should be done with sheets or disks of 120 grit index will be adapted for the first trimming. For the following step, grit index of 240 then 400 will smoothen the marks left by the previous sanding step and improve the touch of the board surface.
For a perfect finish, you will need to use sanding sheets of grit index of 400,600, 800, etc...in combination with water. For a shiny finish, you want to make use of a ''marine'' polishing paste and a sheepskin plate to polish and produce a shiny effect.
For cost and convenience abrasive disks are used on sanding pads of 150mm diameter, and on sticking sheets des feuilles à coller (with repositionable neoprene glue ) on larger pads (200mm).
Please note: For the usage of sanding pads from the brand " Power Pad " or polish & finishing pads "3M" (US origin) on a european machine (Milwaukee, etc...), you will need a 5/8" - M14 adapter .