P3P cracked shell, thoughts?

[Tricky]

This just happened. I had a cracked shell in the arm once before, about 1.5 years ago, sent the whole bird back to dji and they gave me a new one, with a charge of ~$200 for "diagnostic tests" but I was pretty happy to get a whole new P3P for the cost.

Does anyone here have experience with other ways to resolve these cracks besides full replacement?

Many thanks all

 

[Oso]

Do you mean aside from simply replacing the shell yourself? Sending it in, replacing the shell yourself, or one of the countless "glue" suggestions discussed over the years seem to be the options. Personally, I would just replace the shell myself.

 

[Tricky]

Do you mean aside from simply replacing the shell yourself? Sending it in, replacing the shell yourself, or one of the countless "glue" suggestions discussed over the years seem to be the options. Personally, I would just replace the shell myself.

thx @Oso yeah i never really followed along with the glue techniques...and I hate to say time is of the essence as I use this bird for gigs in the northeast USA, and the weather will soon turn unfavorable and my gigs will dry up, but I am not foolish enough to continue to fly with the arm in its current state, no matter how much my gigs pay.

So as you alluded to, I either try a glue method or send her in (again). thx for the reply

 

[Nightwolf]

The top shell is easy to replace and you could reinforce it before install if you wanted to. The crack on the bottom looks small enough to put a little glue on and call it good. I agree, I wouldn't fly without replacing the top

 

[Offroader]

I had a crack just like that on the left rear arm. Tried JB-Weld, but I didn't use it correctly and it fractured. Ended up replacing the top shell. Easier than you think. This video may help:

 

[With The Birds]

While the glue method might work for some polystyrene is difficult to bond successfully.

Don’t be afraid to replace the shell. I just did a second shell replacement on one of my P3 last week. No soldering required, just basic hand tools and a little patience.

A new shell is cheap insurance, and they are cheap.

 

[solentlife]

Just a comment ....

The Top shell where its cracked is bracing to the arm .. it stiffens the structure and its actually the bottom shell that has the real stress. Usually the bottom shell cracks around the motor screws because of that direct stress. Top shell cracks when bottom shell flex's or forces up such as in a strike.

Gluing and adding a thin sliver inside is good for the top. For bottom we need to make sure we get a good bond and my preferred way is to slightly V the crack to allow the bonding agent to fill fully. First I like to use MEK ... this is the Plastic Weld liquid used by plastic kit builders ... it basically is a solvent and welds the joint. But it is brittle so we need something else as well. Normal resins such as epoxy do not bond well to plastic like that and you can over time crack that away. So we need something more suitable ... Polyurethane Glue .. this is a moisture activated glue that expands and foams to fill a joint. Modellers refer to it as Gorilla Glue. You only need a tiny smeer and moisture in the air will set it off ... over the next few hours .. its good idea to wet a finger and pat the expanding glue into shape... or even tape over. PU is very light and tough. It sticks like sh** to a blanket !!

Your choice of course ... as many people find out - replacement shells crack as well !!

Here's a thought ... buy a replacement shell of eBay ... fit and then work on repairing old ready for later when new one cracks ?

Nigel

 

[Vichian-Bruno]

Quick and dirty solution.
Almost 2 years ago when I found a small crack on one of my arms close to the motor I used zip ties on all four arms.
No crack since then and I forced my bird recently up to a speed of 39 mph while ascending simultaneously.

 

[With The Birds]

Quick and dirty solution.
Almost 2 years ago when I found a small crack on one of my arms close to the motor I used zip ties on all four arms.
No crack since then and I forced my bird recently up to a speed of 39 mph while ascending simultaneously.

View attachment 102590

That’s solution will prove useless if cracks are in the lower shell extending to the motor mounting bosses, it will not prevent you loosing a motor in flight.

 

[Vichian-Bruno]

what shall I say, it worked for me and my crack problem, which was btw in the lower shell.
I'm not saying that this solution is the holy grail, just as mentioned, quick and dirty

 

[With The Birds]

what shall I say, it worked for me and my crack problem, which was btw in the lower shell.
I'm not saying that this solution is the holy grail, just as mentioned, quick and dirty

You don’t need to say anything- I’m simply saying your solution will not provide any benefit where the cracks are extending to the motor mounting bosses. In extreme cases the motors become completely detached and obviously from that point the AC doesn’t fly very well. You could put a cable tie in the centre of the lower rail on the landing gear and it would be just as effective.

 

[elent1]

This just happened. I had a cracked shell in the arm once before, about 1.5 years ago, sent the whole bird back to dji and they gave me a new one, with a charge of ~$200 for "diagnostic tests" but I was pretty happy to get a whole new P3P for the cost.

Does anyone here have experience with other ways to resolve these cracks besides full replacement?

Many thanks all View attachment 102545
View attachment 102546
View attachment 102547

I pop the top of all my p3ps and use uv epoxy inside before or after cracks. Fill the spaces in the reinforcing areas a around the screws. they are all flying. Broke an arm and used the same technique..not broke off,just a really big crack. Flight time remains good, range up to 1.5 miles (depends where I fly). I've mown lawns, trimmed hedges, and tried to move trees with them. They're really quite sturdy. The cracking is a material flaw, but I haven't found any better aftermarket products. Since these are outdated now, probably won't be any.

 

[Tricky]

This is a LOT of great feedback, thank you all. I think a variation of glue, and a better inspection of where the shell is and is not cracked, and perhaps popping the top to see what's what, before I ship it back - again that would be lost revenue for the downtime, but...safety first.

I always appreciate the help offered on this forum, thank you fellow pilots.

 

[joeruby]

I have glued my lower P3P shell twice. I now have over 500. miles of flight on this bird. I used "Loctite Super Glue Professional Liquid" I believe I bought the glue at NAPA Auto Parts. It bonds very well to the DJI plastic. The second time I used the glue, I took the motor screws out of the one motor and pulled the motor and wires out (1/2") just far enough to drop in some superglue on the inside reinforcements. Then I sprinkled some baking soda powder to help the glue set up. I kept the powder of the motor mount flat surfaces. I am still flying the bird months after the the two repairs. I keep watch, but as strong as they are, it is not going to fail without me seeing the failure progressing. This will get you going quick. Order a spare shell and keep it handy should you ever need to replace it.
Joe
KC7GHT

 

[Big_A]

You know how annoying it is when you get those fine hairline cracks around the motor mount as Photo 1.
Easy to miss.

Well what I found even more exasperating, was that it tilts the motor, and the props hit the fuselage making a hole as Photo 2
Photo 2.jpg

After a while the blade gets stuck in the fuselage and you get an on screen warning "Motor Obstructed" as in Photo 3. Realy tiresome.
Photo 3.jpg

Then the aircraft starts spinng around and falling as in Video frame grab Photo 4. Could ruin your whole day.
Photo 4.jpg

But this is a DJI Phantom and is a survivor. After a few turns it got the blade free and restarted. Then it righted itself and came home. Hooray!
Photo 5.jpg

I will have to see if DJI will repair this under warranty. Shoddy workmanship.