At what point do u get power armor training from the BOS?? Or is that even where u get it? I've done all the way up to gathering the air filtration parts and I'm going to keep the elder that's already there. Not going with the other guy that wants to over throw him.

After that he says that he'll be busy for a few days. Come back to him later (or use the wait button) and he will assign you a quest that is a lot shorter. After that you get the training.

Sweet thanks just checking I didn't want to FUBAR something up

Your welcome. The FUBAR isn't in the game though...

Yes, you need to return after a wait/sleep for a few days and you will get training. You can also get training from finishing arcade gannons questline and meeting the remnents of the enclave, their armor has more DT.

Also read the wiki regarding getting the armor from the BOS. for two of my characters the elder bugged out and kept telling me to come back, even though I waited months of in game time and played 40+ hours real life time.