Some background... I bought a used P4 standard a couple of weeks ago. It was owned by a young person who had not been excessively gentle with it. The price was good and it's not in bad shape other than some discolouration and abrasions on one set of props and the little covers are missing from the top of one of the landing gear.
It flies well and the images and video are good.
But, during a couple of landings, I noticed some wobble when it was just a few inches above ground. I figured I had an unbalanced prop, so I bought a P4 shaft for my DuBro balancer. It arrived today, but the balancer isn't available to me right now - I'm in the middle of a move from one province to another. I also bought some new (non-DJI) props but they didn't solve the problem. They also didn't make it worse, so I figure it isn't a balance problem, unless the imbalance is the same in two sets of props, but on the same motor.
That got me thinking that there might be an issue with one of the motors being a bit loose - there are signs that the previous owner opened, or tried to open the shell apart at some point. So, I tried wobbling the motors - nope, they seemed solidly mounted. I put on the props to give a little more leverage and to see if maybe there was internal play. WOW... there wasn't play in the motors but two of the props had a bit of play between themselves and the mounts, AND... the other two had much more play. The two with a bit of play just made that nice whirr sound when I spun them. The other two rattled so loudly that I couldn't hear the motors' whirr at all.
These are quick release props. The mounts are the ones with the flat springs. I took the props off and bent the contact points on the springs up a bit to take out some slack. All four props now spun without rattling, but they all still had a bit of play.
A quick visit to Amazon later and I found the newer quick release setup for the 4 Pro. These use a coil spring to supply upward force and engage the locking mechanism. They were $20 (Canadian), so I figured I'd give them a try.
The props now have zero play when they're mounted. And, ok, I didn't think the two mounts with a little bit of play rattled - until I put one prop on the older mount and one on the new mount. I could easily hear the difference. I've attached pictures to show the difference between the old and new. You have to push down a little harder when you mount the props, but they are FIRMLY locked in.
I'll add another post after I fly with the new mounts.
It flies well and the images and video are good.
But, during a couple of landings, I noticed some wobble when it was just a few inches above ground. I figured I had an unbalanced prop, so I bought a P4 shaft for my DuBro balancer. It arrived today, but the balancer isn't available to me right now - I'm in the middle of a move from one province to another. I also bought some new (non-DJI) props but they didn't solve the problem. They also didn't make it worse, so I figure it isn't a balance problem, unless the imbalance is the same in two sets of props, but on the same motor.
That got me thinking that there might be an issue with one of the motors being a bit loose - there are signs that the previous owner opened, or tried to open the shell apart at some point. So, I tried wobbling the motors - nope, they seemed solidly mounted. I put on the props to give a little more leverage and to see if maybe there was internal play. WOW... there wasn't play in the motors but two of the props had a bit of play between themselves and the mounts, AND... the other two had much more play. The two with a bit of play just made that nice whirr sound when I spun them. The other two rattled so loudly that I couldn't hear the motors' whirr at all.
These are quick release props. The mounts are the ones with the flat springs. I took the props off and bent the contact points on the springs up a bit to take out some slack. All four props now spun without rattling, but they all still had a bit of play.
A quick visit to Amazon later and I found the newer quick release setup for the 4 Pro. These use a coil spring to supply upward force and engage the locking mechanism. They were $20 (Canadian), so I figured I'd give them a try.
The props now have zero play when they're mounted. And, ok, I didn't think the two mounts with a little bit of play rattled - until I put one prop on the older mount and one on the new mount. I could easily hear the difference. I've attached pictures to show the difference between the old and new. You have to push down a little harder when you mount the props, but they are FIRMLY locked in.
I'll add another post after I fly with the new mounts.