These maintenance questions get asked constantly, and although there are instructions in the manual, I figured a thread with with all of the information consolidated into one place was in order.
There are two different types of lubrication you will need to perform on your Angel at regular intervals: Oiling and greasing. It's not an either/or thing. They serve different purposes and you will need to do both. Use ONLY synthetic oils and greases - do NOT use solvents, mineral oils, penetrating oils, motor oil, petroleum jelly (Vaseline), or any petroleum-based products.
Oiling should be performed every 2-5 cases.
To oil your Angel, drop 2 or 3 drops of oil into the ASA or macroline and dryfire 20-40 times until oil ceases to "mist" out of your breech. It is a good idea to remove your barrel before oiling so that you don't get oil all over the inside of it and have to go through the pain in the *** of trying to clean it out. After dryfiring, remove your bolt and wipe off any excess oil on the bolt and in the breech. Put your bolt back, close the rotorbreech, and you're done. Again, always use synthetic oils and greases. Some synthetic oils for your consideration are: KC Trouble Free, ACI Airlube or WDP/APS Love Juice Oil.
Greasing should be performed every 15-20 cases.
Grease is applied to three areas at this time: the LPR piston, the mini-reg piston, and the ram o-rings. Specific instructions for accessing these components can be found in the manuals for the various Angel models at www.wdp.tv
To grease your ram o-rings, remove the ram from the body by either unscrewing it, or releasing the retaining pin, depending on which Angel model you have. Clean off the old grease and any gunk that has accumulated. Now apply grease lightly to the front ram shaft o-ring (the only o-ring visible on the ram shaft), and to the three ram body o-rings. Reinstall the ram assembly into the body. Done.
To grease your LPR piston, remove the piston from the body by unscrewing the appropriate front end cap (LED-G7 Fly), or by removing the back plate (A1+), and then pulling the piston out using either an M3 threaded screw, a blunt pick (dental pick, o-ring pick, etc), or the suitable Angel LPR removal tool. Take care not to misplace any of the spring washers or shims. Clean off the old grease and any gunk that has accumulated. Now apply grease to the piston o-ring, and lightly to the piston shaft. Reinstall the LPR piston into the body. Done.
To grease your mini-reg piston, remove the piston from the regulator body by following the regulator disassembly instructions in the manual, or the tutorial in the Ultimate Sticky. Clean off the old grease and any gunk that has accumulated from the piston and spring stack assembly. Now apply grease to the piston o-ring, lightly to the piston shaft, and lightly to the spring stack. Reassemble the mini-reg. Done.
When greasing, take care not to cake the grease onto the parts. The parts should be fully coated in a thin layer of grease, not pasted and dripping with a huge glob of it. Over-greasing causes performance problems by gunking things up and actually making it more difficult for the parts to move. And don't forget, always use synthetic oils and greases. Some synthetic greases include: Dow (Molykote) 33, Hater Sauce, Dye Slick Lube, and my personal favorite: Super Lube Synthetic Grease. On a sidenote: do not use Dow (Molykote) 55 grease on any seals that move (i.e., the regulator piston seals or ram shaft o-ring), as it is designed to plump up o-rings for a tighter seal. Which isn't desirable when you want them moving freely.