Spend like 3-4 motes to level up the last sight/barrel node on blue and legendary special and heavy weapons and select the last node. Once you do that, then dismantle. You will get more parts, motes, and marks (if legendary) than you would if you just dismantled them off the bat. Primaries take like 5+ motes and are a waste since you probably won't get 5 motes back when you dismantle them. For specials and heavies, you'll get 1 to 3 motes, and 2-5 weapon parts per weapon (usually 2 to 4motes total, and 4 to 6 weapon parts total). I've gotten 5 weapon parts from new and old legendaries a few times, and for the new legendaries you can get up to 5 marks just for having the barrels or sights upgraded. Costs next to nothing other than a few motes (which you mostly get back) or a couple bounties. I usually stick a primary I want to keep and level up in the primary slot and throw a blue heavy and special in their slots, pop 3 motes, level up the sight/barrel column, select the last node, then swap them out for another blue special and heavy and keep doing it until I'm out of weapons to dismantle. Rocking court of Oryx for 30+ mins and/or running strikes will get you tons of armor and weapons to do this with. The best part is if you're doing it right, you get the motes back you spend on leveling up the 1st column most of the time, or it ends up costing you a mote if rng is being stingy.

I have around 20 motes of light currently and pretty much the same amount of strange coins. I know about the method you describe. I used it during HoW to gain parts or reforging (and endless buying of Osiris stuff. I absolutely hate trials, however I would sometimes try to get enough wins to buy a weapon for cheap all over again (and then level it up). However, I am not willing to do that amount of micro management anymore. I don't really enjoy strikes anymore. They are boring. The same applies to farming the CoO. It gets old pretty fast. (Patrol is probably the mode I hate the most however) I also do not want to switch my armor and weapons up all of the time just to get a few weapon parts anymore. It's tiring. I just want to play the game, instead of hunting for Weapon Parts, at this point.

Thanks I never even thought of that I have 12 weapon cores in my vault.

Always a pleasure! Level the weapons up a bit and you should get 50 weapon parts easily out of your weapon cores.

Great thanks again, sadly I'm a day 1 player with a ton of hours and I think I have 6 weapon parts across 3 characters lol.