Just wanted to make this quick post to cover a hilarious and silly build that is a completely closed loop (after two seed Filter Inserters). You thresh at least two Filter Inserters to obtain eight Electrical Components and two Inserters. You use five of those components and one inserter to craft yet again two Filter Inserters leaving you with a net gain of three Electrical Components and one Inserter every single loop.
Quick Maths:
5 EC + 1 Inserter (assembler) = 2 Filter Inserters
2 Filter Inserter (thresher) = 8 EC + 2 Inserters
(8 EC + 2 I) – (5 EC + 1 I) = 3 EC + 1I + 2 FI
Build Diagram below:

Credits
►Original Post: https://steamcommunity.com/app/1457320/discussions/0/3802778829223891124/
►Morsk Steam Profile: https://steamcommunity.com/id/morsk
