This might be a dumb question as I'm really new and just got my 5" quad today. While I'm installing the props on the quad and screwed the locknuts on them, I found I can insert my nail in between the props and the locknut. I can spin the props with my hand and the motor won't move. I haven't test flight it yet, as I'm having this question now - should the props be really tightly sitting on the motor? I tried to screw the locknuts really tightly, yet there is still a space between the prop and locknut.

BTW, I bought the pre-build iflight titan xl5, and the props and locknuts came with the box.

Yes, the props should be tight. You shouldn't be able to hold the motor bell still and then move the prop on the shaft. It sounds like you haven't tightened down the Nyloc nuts enough.

The height of the hub on the props should match the bottom of the threaded part on the motor shaft. The props should be tight but not too tight else you may crack the prop hub.

If you have tightened the locknuts and still have a gap or the props are rotating freely along the shaft then perhaps the simplest fix is add a washer below the locknuts.

But I am surprised you are facing this problem with the included props and lock nuts on a pre-built quad.

(09-Apr-2021, 03:05 PM)SnowLeopardFPV Wrote: Yes, the props should be tight. You shouldn't be able to hold the motor bell still and then move the prop on the shaft. It sounds like you haven't tightened down the Nyloc nuts enough.

I see, thanks for the reply.

(09-Apr-2021, 03:09 PM)kafie1980 Wrote: The height of the hub on the props should match the bottom of the threaded part on the motor shaft. The props should be tight but not too tight else you may crack the prop hub.

If you have tightened the locknuts and still have a gap or the props are rotating freely along the shaft then perhaps the simplest fix is add a washer below the locknuts.

But I am surprised you are facing this problem with the included props and lock nuts on a pre-built quad.

Got it. Thanks for the help! I will try to contact the seller to see if they shipped the wrong props, or it should include a washer with it.

You probably just have not tighten the locknut down enough. If it is the nylon locknut, they are very tight at first and takes a bit of torque to get all the way down. Can you post a photo?

(09-Apr-2021, 03:53 PM)voodoo614 Wrote: You probably just have not tighten the locknut down enough. If it is the nylon locknut, they are very tight at first and takes a bit of torque to get all the way down. Can you post a photo?

I think you're right. I was using an auto wrench, which will stop at a certain torque. I think it's tight enough when it stops. As you mentioned, now I use a manual wrench to tighten the locknuts down, and the props can stay securely on the motors now, with no gaps between props and locknuts. Thanks a lot for mentioning it.

Do prop manufactures have an actual torque value?

(09-Apr-2021, 07:58 PM)Kevin2112 Wrote: Do prop manufactures have an actual torque value?

Not that I'm aware of. I think I'll keep my torque wrench for doing jobs on the car I just tighten my prop nuts as tight as I can by hand while holding the bell as tight as I can by hand to stop it slipping round. When I can't hold the bell still any longer and the props aren't slipping round on the motor spindle I deem them to be tight enough.

You'll get used to the right tightness. When you turtle mode and they instantly come loose your not tight enough, if they stay on their tight enough.

(09-Apr-2021, 08:39 PM)EVILsteve Wrote: You'll get used to the right tightness. When you turtle mode and they instantly come loose your not tight enough, if they stay on their tight enough.

True, it just happened as I test flight it yesterday. I thought I tighten it enough, but one prop just got loose when I land my drone and it bumps a little bit on the ground.