Item synthesis
Item Synthesis is the process of using a Partner Machinery in order to create items (such as weapons, armors and consumables) from base materials which can be bought from Synthesis Shops or found while doing Missions.
Process
Step 1: After 'feeding' your Partner Machinery the proper recipe board, put into your storage the proper materials the recipe calls for. Note the big fat red Xs listed, those are telling you you don't have the proper materials in the personal storage (You just can't have the items on you).
Step 2: Verify with your PM that the ingredients necessary are there. Note the success rate for your item as well as the number of uses left that recipe can generate at the bottom.
Each type of item built will follow a standard formula that never changes: General items that are catalysts (not usable, like grinders, or resource refining with the exception of high level ore refining), consist of 1 item, which is usually the material itself, and labelled as such (Stuff like "Grinder C Parts".) Usable items (mates, atomizers, scape dolls)and high level ore refining consist of 2 types of ingredients, food items (berries, truffles, etc), and acids for usable items; lower level ore and basic photons (yes basic, not elemental, or even the higher level ElPhoton) for high level refining. Armors require 3 kinds of resources - photons, ores, and materials (such as nanocarbon, or orta-resin). Finally, weapons require the most of anything, filling all 4 resource slots, consisting of Photons, Metals, Ores and Wood.
Step 3: Wait the specified amount of time. Since it does take your PM time to create weapons like any blacksmith would, you gotta wait the time necessary. In the example here, there's 46 minutes left (Originally this weapon was 90 minutes). The stronger the item, the more time it takes. If it's an armor, it takes even more time. If its got a success rate of 100% (usable items and most forms of refining), it will be instant. Note that you can cancel it and get back your materials should you have to, however, if a considerable amount of time has passed, you may not be able to get back the materials USED. You can check on the status of your weapons, and how much resource has been used, anything unused will be returned to you, anything used has a success rate of retrieval. The synthesis process might take several hours.
Step 4: Finalize synthesis, and pick up your items. At this point, you can still cancel synthesis and make an attempt at getting your resources back. Picking up only applies to armors, weapons, and high level refining. This is essentially the moment of truth, time to see if your PM successfully created/refined the item or not. If you fail, you'll end up with junk, such as Monomates.
- NOTE: If you evolve your Partner Machine, the synthesis success rates will go up. Sometimes success rates can go up to 10% with one evolution.
Credits to Lyrise of PSOW forums