How to unclog drains without aggressive products

This video shows how to unclog and clean a drain, I have focused on a sink drain but it is similar to the rest. In this first video, each of the elbows is disassembled and cleaned, including those that form the siphon, in the second video it is shown how to assemble an economical tool to clean the pipe connected to the downspout of the house's drain. Do it yourself.