Torque Tube Issue/failure

[Deet]

I just had a look at a torque tube that looked intact after the boom got bent in a major incident.

It is one I did the heatshrink on. It all looks fine except when you hold the two splines and twist there is about 5 degrees of play in the TT.

After stripping it down, i found the holes in the TT itself where elongated, and 1 of the spline screws was completely stripped.

So basically if you go in you will probably want to replace the TT and the splines anyway. So go the JB weld, and the heatshrink I say...

Funny thing is all the TT gears, the tail shalt, grips, links etc all survived, so it seems the TT took the worst of the impact damage. Along with the main blades, main gear, one servo horn and one set of servo gears.

The rest of the heli looks like it hasn't even been flown, this is one AMAZINGLY tough heli.

[devens]

Everyone keeps talking about using red locktite. I use Locktite Brand thread locking compound and red is heat resistant, blue is normal and green is permanent. I assume the red you guys are using is permanent type?

D

[DominicD]

its really not perm. just don't use too much of it.

[Foxden]

Originally Posted by devens

Everyone keeps talking about using red locktite. I use Locktite Brand thread locking compound and red is heat resistant, blue is normal and green is permanent. I assume the red you guys are using is permanent type?

D

Any Loctite can be removed with a heat gun and some patience,

Loctite Red 262 High Strength

Loctite Blue 242 Medium Strength

Loctite Blue 243 Medium Strength, Oil Resistant

Loctite Green 609 Retaining Compound

Loctite Green 603 Retaining Compound tolerant of oil and other contamination, great for bearings to shafts

I have a 50ml bottle of 243 in the shop for building, and carry a 10ml bottle of 243, 262, and 603 in my field bag.

Here's another tip when dealing with bolts that have red loctite, once removed the bolt threads can be easily cleaned and reused by simply running a die over the threads, does a nice job of removing the old red loctite, I keep a 2.5 and 3mm die in my field bag just to chase the threads.