There are two reasons people would run missions in Swtor, the first is to level up their Crew Skills and the second would be to gather materials for what Crew Skills they have. This guide is for the latter. Now believe it or not running missions with your Crew Skills is one of the best ways to gather materials. You can gather almost any material that is required by your profession just by simply running a few missions. Depending on what Crew Skill you are using to run these missions will determine the type of items you will be getting.
All of the gathering crew skills (Archaeology, Bioanalysis, Scavenging) all reward similar items for their crafting crew skill counterparts. However, other Tradeskills such as the mission skills (Diplomacy, Investigation, Treasure Hunting and Underworld Trading) all reward more rare and difficult to obtain materials. One of each of these professions is required to maximize your potential in any crafting skill. Below is a list of each of these tradeskills with a page leading you to the materials you're able to gather at rank 6.
Investigation (Armstech +Recipes for all Crew Skills)
Treasure Hunting (Artifice)
The type of materials you can gather from the Gathering Crew Skills and the Mission Crew Skills are totally different. As an example one recipe for Synthweaving may require Crystals from Archaeology and Metals from Underworld Trading. Both the Mission Crew Skill and the Gathering are required to maximize your potential in any Crew Skill. The only ones that work semi-independantly are Slicing, Bioanalysis and Investigation. When it comes to sending your companions out on missions it will be tricky to maximize the potential of rewards. I've found a good balance to be...
3 Gathering Skill
2 Mission Skill
When you need to craft any items you'll want to very slightly switch that order up to be.
2 Gathering Skills
1 Crafting Skill
2 Mission Skill
Each Rank 6 mission for Gathering Crew Skills takes about 30 minutes to run and will reward you with a decent amount of materials. If you have a lot of affection with your Companion it will lower the time it takes to complete one of these missions. These missions will reward you with all of the easy to find materials for your Crafting Crew Skill.
This section is to go over all the materials you will be getting with Gathering Crew Skills.
Each Rank 6 mission for the Mission Crew Skills takes about an hour to run and will reward you with a decent amount of rare materials. If you have a lot of affection with your Companion it will lower the time it takes to complete one of these missions. These missions will reward you with all of the hard to find materials for your Crafting Crew Skill.