Old Russia Destiny Spinmetal Farming
One of the good farming routes for Spinmetal in Destiny is in Old Russia. Stick to the right side of the map until you get to a scrapyard area with old planes, trucks and machinery. In this area there are several spawns of Spinmetal, in particular under plane wings, near broken planes and trucks. Near the rocks are also caves which have chests spawn in them from which you can also get Spinmetal. Decide on a Spinmetal farming route and keep going around it until you have enough Spinmetal for your upgrades.
Rocketyard Spinmetal Farming
Another good farming route for Spinmetal in Destiny is in the Rocketyard. Go to the second section containing the oil tankers and vehicles. There are a number of storage houses in the area which have chests spawn in them giving you Spinmetal and Glimmer.