Propeller slightly chipped

[Txiku]

Is this too much damage and *must* be replaced?

 

[Felix le Chat]

That's not a chip: that's a gouge. Yes. Replace, to maintain balance, best to replace all 8 at the same time.

 

[Max Headroom]

best to replace all 8 at the same time.

I flew my 2 SE slowly into a tree i changed the props that were damaged and it flies perfectly, why change them all?

 

[msinger]

@Txiku the angle in your photo makes it tough to clearly see the damage. In general though, it's a good idea to swap out damaged props prior to the next flight. While some recommend always changing the entire set or changing them at set time intervals (even when not damaged), I think replacing just the damaged props is a safe enough practice.

If that prop struck a solid surface, then you'd especially want to inspect this area of the prop to ensure there aren't any cracks or other damage that could weaken the hub area:



Must you replace it? No. I think it would be a good idea though since replacing a prop is much cheaper than replacing a drone crashed due to flying with compromised props.

 

[MS Coast]

If that prop struck a solid surface, then you'd especially want to inspect this area of the prop to ensure there aren't any cracks or other damage that could weaken the hub area:

That's an excellent point about checking the hub, too, instead of just focusing on the blade portion of the prop. I've updated my preflight routine.

 

[Max Headroom]

replacing a prop is much cheaper than replacing a drone crashed due to flying with compromised props.

Excellent advice.

 

[tstr14]

That leading edge is a key factor in a prop's dynamics. Replace it.

 

[Txiku]

Thanks all, and thanks @msinger for the advice on checking the area around the screw. No damage there as far as I can make out.

 

[Max Headroom]

One thing i didn't realise when i recently got my drone is that the spare props that came with it have 3 new screws in every pouch of 2 props.

 

[hiflyer201]

It needs to be totally replaced

 

[Yorkshire_Pud]

Replace both blades on the relevant motor and use blades from a single DJI pack.
They are supplied, by DJI, as, presumably, a balanced pair and should be fitted to one motor as such. I don't see the need to replace ALL the props unless at leat one blade on each motor is damaged.

It has been said that if you can COMPLETEL match-up the raised letters and number on two 'odd' blades they will be balanced pair I do not know if that is true.

Peronally I use ONLY DJI blades and wouldn't use blades from other sources, especially if they ARE NOT supplied in natched pairs.

 

[BlueHeeler]

That prop blade would be going into my round file, props are cheap, drones are not.

 

[AeroJ]

One thing i didn't realise when i recently got my drone is that the spare props that came with it have 3 new screws in every pouch of 2 props.

View attachment 177662

And those are pre-threadlocked, so we should use them when we change blades, and not re-use the old ones.
Some people doubt the reliability of pre-applied threadlocker, but if it was problematic here we would get many more reports than we do that it fails. I'm a great believer in applying liquid threadlock as I fit screws, but obviously we don't want that anywhere near open motors.

 

[Max Headroom]

And those are pre-threadlocked, so we should use them when we change blades, and not re-use the old ones.

I did wonder if that was the case when i found the new screws in the pack, like an idiot i had already put the old ones back in i will check them before each flight and at battery change time when i am flying, i used to do this with my petrol engine RC car as it vibrated so much so its not a problem or i may get some thread lock and carefully apply it just to be on the safe side losing a car doesn't have the same consequences as losing a drone in full flight.

 

[Fizzbang]

Is this too much damage and *must* be replaced?

Any prop damage is too much damage.

 

[Max Headroom]

Deleted.

 

[Dogpilot]

Just a little education on props in general. I actually have my engineers license for aircraft, but it does not cover propellers, a true speciality. I can inspect them on the other hand. Props generally have a diagram for allowable damage so many inches from the hub and location in reference to the cord. Varies depending on make and material. The big general take on it is: you can have damage in the last ¼ of the length, re-balance may be required. You can have virtually no damage in the mid length. Why is that? It is where most of the flex in the blade occurs. Any damage causes stress risers and they propagate quickly in the mid blade area. Hub cracks happen from what is called "Sudden Stoppage." Which can be anything from lots of grass to piles of dirt or rock. One might say Grass! Well these things are not lawn mowers. Mowing causes small changes in acceleration of the blade, stressing it. Stress causes cracks, cracks cause... You see where this is going.

The regulations on prop damage and striking virtually anything have evolved in the last decade. It was found, far too many times, things like even crankshafts were breaking off at the flange from what was perceived as minor strikes. So if your drone hits something, spring for the $10 blade set. Which realistically is 1.5 cups of coffee at today's prices at some chain.

 

[Txiku]

Thanks for that @Dogpilot.

I've replaced both propeller blades (Set A) on the right. Noticed that the propeller model/serial number (had to look through a magnifying glass) is different to what was installed out of the box. The left props at the front (Set B) are 16030F 5, the ones I've removed and replaced were 16030F 4 and the news ones are 16030F 2 . Can it be expected these digits will differ in spare props? Very possible that the other spare props I've got are also different. Does this really matter? My understanding is that the Mini 3 Propellers are compatible with Mini 4 Pro.

Also noticed that the screws I replaced along with the props don't seem to "fit" as well as the ones I unscrewed and replaced and although its not a good idea to apply too much pressure, I did have to apply a little otherwise the screws are not fully in place. Still not as snug as the others. Maybe, its just my OCD but wonder if others have faced this issue.

 

[Max Headroom]

Do you mean the blades move more freely on the new screws or they don't tighten up properly?

 

[Txiku]

@Max Headroom Blades move freely as expected as far as I can judge, but the new screws protrude more. Not able to tighten as much as the previous ones. Not sure if the attached image is able to reflect this. Compared to Image A, the screws in Image B appear to not be able to tighten any further. Is this likely to cause an issue during flight? Tried unscrewing and re-screwing but this is about as tight as it can be screwed.

P.S. The DJI screwdriver supplied out of the box is absolute shite.