This is a large  WS2812b led matrix we designed for customer the whole size is 240mm*900mm in P15mm, 

 total Pixel (16*60) we soldered 2 pcs 240mm *450mm it makes easy installation when you're going to use 

the addressable tape to make a screen, less soldering point and Pitch exactly same as you want.
 Do not concern about the heat based on such a thick Copper PCB in want of perfection , it's just IP20 indoor 

use only, you should make a IP65 case to hold the panel when you're going to put outdoor we don't promote 

this products but welcome share idea and let's make it possible Customization.