Benefits of water cooling for printer

What’s the pros? And is it necessary? Saw someone with a modded printer and he was saying he added custom water cooling.

I just have fans to cool the print as printing. What’s water cooling used for?

Pros= None for the average hobbyist
Necessary= No, not for the average hobbyist.
It is used to cool the extruder, not the print object.

Super exotic filaments (Polycarbonate, Nylon, etc,) require extrusion temperatures of 270-300*C. It is engineering challenge to keep that much heat from transferring from the heater-block to the cooling-bar and motor. This is known as the “transition-zone”. Filament has to stay cool before reaching the “melt-zone”(nozzle). Printers have recently been engineered with larger “cooling-blocks”, larger “cooling fans”,or even extruders with “cooling-fins”(E3D), in order to keep up with the new filaments that require higher temps. But those changes can’t meet the demands of super exotic filaments. A “cooling-block” is basically just a large chunk of aluminum, so running water thru them is a logical means of controlling “heat-creep”, at extremely high temps.

Unfortunately, this will add excessive weight to the moving gantry, and cause poor quality prints. Only custom built printers, with massive linear guide rails, will be able to control that much weight and inertia.

Thanks for the explanation. I was looking into getting a water cooling system for my PC, so I thought I might also look into getting one for my printer. But I definitely do not use extremely exotic filaments. PET is about as fancy as I get at this stage.

Thanks @Gene_Crady!