Are you supposed to spread open the propellers before you fire it up?  Or just let the centrifugal force open them up?  I couldn't find anything in the manual is there an official instruction from DJI?

Hello and good day kcole0929. Thank you for reaching out. You should unfold the propellers of the DJI Mavic 2 before the flight. You can also refer on the attachment below for our pre flight check list. Thank you.

hi - a video was posted recently comparing a start up with props folded vs unfolded. although centrifugal force quickly unfolds the blades it is clear in the video that considerable unnessesary forces play out at start up vs none at start up with unfolded blades. ..
and dji recommends startup with unfolded blades

You can  start  with it folded or opened.  It s your choice

I always unfold them. Yes, they will unfold by themselves during motor spin up, but that's a lot of unbalanced load on the motor bearings.

Sometime I wish my shoelace would tie itself lol

REMOVE DC NFZ Posted at 3-25 08:02
Sometime I wish my shoelace would tie itself lol

Like Back to the Future 2! And a self-drying and self-fitting coat would be nice too.

I've forgotten once or twice to unfold them and no apparent harm was done. However, DJI recommends unfolding them to reduce un-needed forces on the motors and prop hubs.

Look at this video. This will happen when you start up the drone with props unfolded. A lot of stress on the engine arms.
https://youtu.be/FfwDPs76LgY
https://youtu.be/RYmRRwyO5bI

dronie1965 Posted at 3-25 09:17
Look at this video. This will happen when you start up the drone with props unfolded. A lot of stress on the engine arms.
https://youtu.be/FfwDPs76LgY
https://youtu.be/RYmRRwyO5bI

Holy Smoke!! This will end the 'should I unfold my props' question for good. Thanks for that!

You’re welcome
Yes its indeed better to unfold

dronie1965 Posted at 3-25 09:17
Look at this video. This will happen when you start up the drone with props unfolded. A lot of stress on the engine arms.
https://youtu.be/FfwDPs76LgY
https://youtu.be/RYmRRwyO5bI

Wow! Thanks for posting this. I've always unfolded mine because I check for nicks and cracks plus make sure they're on good. Doing that, they get unfolded, hadn't even thought about doing it just for the sake of unfolding them.

dronie1965 Posted at 3-25 09:17
Look at this video. This will happen when you start up the drone with props unfolded. A lot of stress on the engine arms.
https://youtu.be/FfwDPs76LgY
https://youtu.be/RYmRRwyO5bI

I have always unfolded my props and after watching this I'm glad I do. Thanks for posting it!

Certainly looks like unfolding the props before start up would be a best practise - thanks for posting the video

I think spreading the props will be less stressing to your motors, and it takes 5 secs to perform it....