Loctite on servo horns?

[Torben]

Hi
I have a question about loctite on servo horns.
The servos are Align ds510m and ds520.
Is there anyone who knows these servos and use loctite on them? They all have lock washers but is that enough?
I know that I only can use loctite on metal to metal parts.
Torben

[Geena]

I do. I think it`s better to be safe than sorry. Just my opinion though.

[Luvmyhelis]

Originally Posted by Torben

Hi
I have a question about loctite on servo horns.
The servos are Align ds510m and ds520.
Is there anyone who knows these servos and use loctite on them? They all have lock washers but is that enough?
I know that I only can use loctite on metal to metal parts.
Torben

Not on the arms themselves. But on the seating bolt threads only.

[Vinger]

Never used threadlock on any servo screw, as they are kept on with spring washers and that is more than enough. Far too difficult to remove if you use threadlock.

[svensson_bo_l]

Originally Posted by Torben

Hi
I have a question about loctite on servo horns.
The servos are Align ds510m and ds520.
Is there anyone who knows these servos and use loctite on them? They all have lock washers but is that enough?
I know that I only can use loctite on metal to metal parts.
Torben

Since it is a metal screw that goes into metal, I do.
When the arm is in position I apply some loctite in the hole
with something thin, like a toothpick.
In general lock washers should do the job, but I don't use them on horns.

Regards,
Bo

[myxiplx]

Loctite shouldn't be used where it can come into contact with any plastic part as it will weaken the plastic.

And if you have locking nuts you shouldn't use loctite there either.

With those provisos in mind, I use loctite on every single metal to metal screw on my heli's. On servos I'll use a toothpick to apply loctite inside the output shaft before I attach the servo horn.

[jharkin]

Originally Posted by Vinger

Never used threadlock on any servo screw, as they are kept on with spring washers and that is more than enough. Far too difficult to remove if you use threadlock.

Sooner or later you will loose a heli over that.... More than once Ive seen the screw back out when relying on the washer only. I've even seen them come loose with loctite when too little was used or the screw was oily.

Blue loctite is not hard to remove at all when used properly. Just avoid red.

Rules of thumb-
Metal gear servo - always use blue loctite.
Plastic gear servo (white nylon or the hitec "karbonite) - never use loctite.

The above rules apply regardless of whether the servo arm is metal or plastic. Just keep the loctite on the screw and dont get it on the servo arm

[Diogenes]

Originally Posted by Luvmyhelis

Not on the arms themselves. But on the seating bolt threads only.

This, I put a small amount (~2 threads) if the servo gear is metal with a toothpick

[onemorecrash]

Oh man this brings back memories of my 600 pro
Going down cause a servo screw backed out on one of my servos. I did not use locktite.on them cause I forgot
They were metal. The ones I use now on my 550 are plastic so no locktite.on them but the screws go in nice and tite.and I check them often.

Back when we raced monster trucks we would use. jb weld. On the top of the servos to keep them from backing out. It's extreme but it worked for us.
Not sure if it's a good idea on helis though

[HEXAHYDRATE]

+1 to use thread locker.

I have seen servo horn screws come loose as well. Use thread locker.

[Carder]

I have two trex 500 with those servos and use Loctite on them it's a must

[Corvette & Copter Guy]

Originally Posted by HEXAHYDRATE

+1 to use thread locker.

I have seen servo horn screws come loose as well. Use thread locker.

+1
It happened to me.

[PowerDyne]

I too use blue Loctite 242, in small quantity (first 2-3 threads just to wet them) on servo screws going into a metal output shaft. I also use socket head cap screws in the proper size to replace any button head or Phillips head screws used on servo arms.

The reason is it's easier to get the screw out without stripping the head of the screws. To break them loose for maintenance or repairs, just hold the servo horn in place with one hand. It helps not to heap the loctite on when installing.

Running nitro helis especially, loctite needs to happen on servo horns.

If your output shafts are plastic, no loctite.

[macdad]

I crashed a 450 due to a servo horn screw backing out. I have used blue loctite on them ever since. They will back out over time.

Never on the ball link that screws into the servo horn, though. Unless, of course, you are using an aluminum servo horn.

[Dylan Hudock]

Like everyone said above, use loctite. The rule applies here as well, use it when the screw/bolt is going into metal only. If it is going into plastic it is not needed, and will destroy the part you put it into. There are no exceptions to putting loctite on metal to metal joints, unless you want your heli to come apart.

[Vinger]

Well actually a lot of exceptions! If the servo arm is composite or plastic no need for threadlock as the springy washer and give in the servo arm will hold the screw in. Metal servo arms you can use threadlock if you want but personally only use the spring washer and have not had a single servo screw come out in over 10 years of helis and 20years plus of planks.

Jan Henseleit recommends in his manual to NOT use threadlock on bolts going through composite or plastic into metal threads as the composite has enough give to keep the bolt in. Since 2009 not a single bolt from any of my helis have come undone following his recommendation. On the TDR there are even ZERO threadlock on the bladeholder bolts into the spindle shaft.

[Spazztl]

i crashed my oxy and x3 because of screws backing out of the servo horns.
I loctite all my metal servos now. i never became a spring washer with any of my servos , and that's where alot of manufacturers are saving(cutting cost) i think.

[Heli$]

I loctite my helis except my X5 which has seacraft servo horns. Those dam things will never come off.

[Magnumeng]

Alway loctite metal to metal screws... Did not do it on one of my first copters and had to land a ccpm copter on only 2 servos... NOT fun, got lucky as hell

[jharkin]

Originally Posted by Vinger

Well actually a lot of exceptions! If the servo arm is composite or plastic no need for threadlock as the springy washer and give in the servo arm will hold the screw in. Metal servo arms you can use threadlock if you want but personally only use the spring washer and have not had a single servo screw come out in over 10 years of helis and 20years plus of planks.

Jan Henseleit recommends in his manual to NOT use threadlock on bolts going through composite or plastic into metal threads as the composite has enough give to keep the bolt in. Since 2009 not a single bolt from any of my helis have come undone following his recommendation. On the TDR there are even ZERO threadlock on the bladeholder bolts into the spindle shaft.

Maybe you can get away with that if you are doing electric only... but sooner or later it will bite you on nitro / gas.


Ive also done planks close to 20 years and I have had metal gear servo screws back out even with loctite, very lucky to have caught it in the preflight each time. Seen it happen to others also, with fatal result.