Used Loctite 242 (Blue) On Motor Mounting Screws

[lil boss]

I just now saw the "not for use on plastic" warning on that tiny tube of Loctite. Originally I had removed only one motor. The screws were in really tight from the factory, and so thinking that was correct, I tightened the screws with about the same force as I used when I took them out. That is when I first used the Loctite. Then I noticed cracks coming from the screw holes. When I saw the cracks on the one arm I read that DJI had over tighten some motors at the factory and to just loosen and re-tighten snuggly. So I'm not sure if the cracks are from me over tightening, or the Loctite. Not being happy about the cracks I removed all the motors, and placed some epoxy into the shell around all the screw holes to be safe. After the epoxy had cured (24 hours) I installed the motors (snug) with more loctite on ALL the motors. An hour after I had all the motors installed with the loctite I saw the warning >>> SHOOT !! I quickly removed all the screws. There are no "new" cracks at all. Only the first set of cracks on the one arm. No cracks on the remaining 3 on which I used Loctite, but did not overtighten. So my question is.. What Now ?? I see no crumpled plastic or other damage which others have described from the Locktite.. Should I just reinstall with no Loctite and keep an eye on everything ?? Or should I replace the shell ? Thanks for your thoughts... In the meantime.... HAPPY HOLIDAYS !!!

 

[msinger]

It's not safe to use Loctite on the shell screws. You'll need to replace the shell to resolve this issue. If you're going to do the work yourself, you can pick up a new shell here on Amazon or directly from DJI here.

 

[notsolowki]

those cracks are superficial i doubt they will cause any problems

 

[Mark The Droner]

Since the motor mount screws are installed into the motor, and since neither are plastic, I don't see a problem. And we all know the factory uses blue loctite or a similar product. I suspect the cracked plastic is from over-torque.

 

[N017RW]

Sadly the shell is ruined as msinger has pointed out.
It's not just physical contact as the fumes during curing have caused the plastic to become brittle.
This is described in the product literature.

The Blue thread-lock used by DJI is pre-cured and thus no fumes are present at time of assembly.

Regular inspection negates the need for reapplication of any TL as I have never added any.

 

[Mark The Droner]

The fumes! Good to know.

So in other words, applying the loctite to the screws and then allowing them to dry before installing them would be okay?

 

[N017RW]

Well, I don't know what the type/composition of the DJI TL is so I cannot say that Loctite would be safe if used in a similar way.
It would seem logical if the curing is complete and the TL was 'neutral' that it would be safe. But I can't confirm that.

My experience has never required me to add TL to any of my Phantoms, the oldest being a P2 from mid-2014.

 

[RW-1]

For the shell screws no, for the motor mounting screws - sure.

I've used Blue LocTite on my model heli all the time, frame is glass reinforced nylon though.

I don't believe your one time use on the shell screws will do anything, if they remain tight. Your shell replacement is mroe towards the overtorque on them than the use of the loctite once.

 

[msinger]

I've used Blue LocTite on my model heli all the time, frame is glass reinforced nylon though.

Loctite is a no-no for Phantom shells. It is a known fact that it destroys them.

 

[RW-1]

Loctite is a no-no for Phantom shells. It is known fact that is destroys them.

Well, that blows, eh?

 

[lil boss]

Thanks Guys For All Your Thoughts And Advice. I'm going to play it safe and install a new shell. Does suck though... although it's my fault for not catching it before the fact. Cheers To All And Happy Holidays !
Edit... I took a look at a hardware kit I ordered from DJI and I see that some of the screws have the Blue LT or whatever it is on them. So I'll being using the new hardware to put this bird back together.

 

[montelatici]

Just use nail polish any color. It will lock the screws.

 

[lil boss]

Just use nail polish any color. It will lock the screws.

Thanks Man, Great tip, I'll get some tomorrow. Have A Good One !!

 

[montelatici]

Merry Christmas!

 

[lil boss]

Merry Christmas!

LOL.. You Too... Merry Christmas !! I'll have a good few days off and will enjoy tinkering with my Phantom !!!

 

[seaquadrone79]

Lock tite on the motor mounts are fine. The cracks were caused from over torque. They say to only tighten the screws two finger tight no more. They do use lock tite on the notorious mounts none on the shell.

Sent from my SM-N920V using PhantomPilots mobile app

 

[seaquadrone79]

Motor not notorious

Sent from my SM-N920V using PhantomPilots mobile app

 

[lil boss]

The Shell Change Went Off Without A Hitch. It's too cold to test outside, so I removed the props and fired her up inside. All Is Well !! Thanks Again, And Happy New Year !!