Undercoating is really just another way of saying "priming," which we discussed in depth last week. It's probably better to use the term priming anyway, as "undercoating" can be confused with "basecoating."
We also discussed UV resin last week, in terms of 3D printing. But UV resin also has other uses.
In printing, UV resin is deposited in thin layers and then cured with ultraviolet light to harden it into models. You can actually achieve similar effects by pouring the resin into a mold and then hitting with a UV light.
In modeling, UV resin is often used to make glass or water effects (materials that have a translucent appearance).
You can also use silicone to create a mold, often by pressing it against a piece or texture you want to copy, and then fill the mold with resin to make a copy of the original piece. I've seen it used by people customized their miniatures, to create new shields, armour, or elementals to add to the base (like skulls, rocks, etc.)
Just a short post today, tomorrow should be more interesrting and involved. The end is in sight!