Be careful when/if using Loctite!

[Bart1]

I had a motor getting really noisey, so I decided to replace it. Got a new motor and installed it. When reinstalling all the screws, I added a drop or two of the Blue (non-permanent) Loctite into the thread holes for each screw and proceeded to tighten them all up. Everything appeared fine.

Next day, ready to go flying, do a standard pre-flight check and noticed that a screw appeared to be loose... Closer inspection revealed that the Loctite had eaten away the surrounding plastic and when I turned the Phantom over, several scews fell out onto the floor!

Apparently, Loctite and plastic are not friends. Every hole that I had used Loctite on was ruined, the Loctite simply ate the plastic away so there's nothing remaining for the screw to screw into.

ARRRGGGHHH!

Fortunately, RedRocketHobbies (in Oregon) had a spare Phantom shell and I'm now in the process of transferring the innards from my old, half-eaten Phantom shell into their new body.

[Expensive] lesson learned.

Note to self: no more Loctite anywhere near plastic!

 

[MRSpyder2U]

Yes, if you do a search on "Loctite" you'll find countless references to your discovery. Sorry for your problem, but glad you'll be back in the air soon.

 

[darkhorse]

If you must use it, Loctite comes in a tape and also in a glue stick form, much easier to control than the liquid.

 

[Gizmo3000]

It can be a bit deceiving , since all the screws that DJI provides has a sort of three-lock material applied to them.
I'm still wondering just what that stuff is.

 

[Bart1]

I contacted Loctite and asked them if they had a product that was safe to use on or near plastic and was informed that basically they do not. When I asked about the Loctite tape, the rep informed me that it, too, was unsafe to use near plastics (so I'm wondering what product was used on the original Phantom screws?)

Anyway, after further discussion, I was informed that they do make a type of low adhesive SuperGlue (they call it Loctite 425) but that it is only available through commercial or industrial suppliers and not sold at the retail level.

Maybe I'll try plumbers tape. Or...I wonder if plain old white Elmers glue would do the same thing...

 

[growe19]

I asked the dealer about loctite when I bought my Phantom and they advised not to use it on any of the parts, not required.
Sorry to read about your problem.

 

[steadicamhawaii]

fingernail polish maybe

 

[freelanceshots]

Thanks for taking the time to post this warning. Was considering loctite in the back of my mind if the screws loosened up after taking my shell apart. Now I know to forget that.

 

[auck]

has anyone tried plumber's teflon tape instead of locktight?

 

[MRSpyder2U]

Something that I used many years ago (before there was dirt and people could see in color) was a sugar/water solution as thread-lock. If I remember correctly it was mixed 50/50. If you try this, heat the water first so the sugar dissolves better. I think it's called simple syrup, now. I've heard that maple syrup, molasses and other sugary concoctions work just as well. I don't think sugar or water or the combination will harm the plastic. Anyone who has spilled a sugary drink into a keyboard can attest to its ability to gum up the works. Just an idea. Use it as you will.

 

[freelanceshots]

what about a small dab of clear fingernail polish. The poor man's loctite.

 

[Duncan Campney]

I had a motor getting really noisey, so I decided to replace it. Got a new motor and installed it. When reinstalling all the screws, I added a drop or two of the Blue (non-permanent) Loctite into the thread holes for each screw and proceeded to tighten them all up. Everything appeared fine.

Next day, ready to go flying, do a standard pre-flight check and noticed that a screw appeared to be loose... Closer inspection revealed that the Loctite had eaten away the surrounding plastic and when I turned the Phantom over, several scews fell out onto the floor!

Apparently, Loctite and plastic are not friends. Every hole that I had used Loctite on was ruined, the Loctite simply ate the plastic away so there's nothing remaining for the screw to screw into.

ARRRGGGHHH!

Fortunately, RedRocketHobbies (in Oregon) had a spare Phantom shell and I'm now in the process of transferring the innards from my old, half-eaten Phantom shell into their new body.

[Expensive] lesson learned.

Note to self: no more Loctite anywhere near plastic!

Ouch. I got a set of 3rd party removable prop guards and used blue locktite on ALL the screws (all 4 screws on all 4 motors) when installing them. I've flown my P3 quite a few times since, and the screws seem fine. I used a TINY amount on each screw. I guess I got lucky.

 

[NCFlyGuy]

I too have used loctite on my Phantom but I have not had any plastic degeneration or cracks. (old motor/shell design) I applied a miniscule amount using a toothpick and allowed it to setup a bit before reinstalling the screws. This was ONLY done to the motor mounting screws with only metal to metal contact. There was no damage to the plastic since there was no loctite to plastic contact.
You won't do well to insert screws dripping with loctite. You just need the exact amount necessary for the job.

 

[Martin Smith]

A single drop of elmers glue will prevent the screws from vibrating loose and yet when you wish to remove the screw with a tool they will come loose with moderate pressure.. I use a single drop of elmers glue often and works great.

 

[NormanNormal]

Thanks for the heads up, this is good info to know. Sorry it happened to you, though.