700E v3 tail screws

[RV_7A]

Not sure why align used a screw top and bottom here. The bottom one fell out so I replaced it with a long 15x2.5mm screw, washer and nut. All blue thread locked. If I would have had another screw of the same I would have replaced it and kept flying but I had to improvise. I think this will be more reliable.

Jeff

[K2Freak]

Yeah, looks great!

JK.

You always need to disassemble anything Align, clean the threads with alcohol, and then reassemble with loctite. You may want to find the original screw size and get new ones into both top and bottom to minimize the play within that joint...

[RV_7A]

That photo was just to clearly show what was being done. Silly boy.

[RV_7A]

Here ya go silly boy ;o).

[RV_7A]

There is no play. The screw tightens down on the top bearing and the nut tightens on a small washer on the bottom bearing. The threaded holes that both the original screws were in is tapped all the way through that lug.

[K2Freak]

Heh heh heh...

I seriously thought that you had bottomed out that long screw into the top. Would NOT be the most ridiculous thing I've seen here! Mine are not drilled, so I assumed...

That looks a little more reasonable.

[RV_7A]

LOL. I hear that. My bad for NOT being clear as to what I was trying to get across. Anyway it's a pretty straight forward reliable change.

Jeff

[ualdrivr]

What prevents that nut from coming lose? Probably nothing. If you want to go that way, although I don't know why? I would use a locknut.

I have that same pitch slider assembly on both my Nitro and E and nothing's come lose. Mind you the Nitro vibrates a lot more than the Electric does. You can use all the Locktite in the world, if your threads have machining oil on them, that Locktite is useless

[ddj74]

Not sure what you are referring to as "play" but that part on my heli has zero play with double sided screw. I've ran that same setup on my old 500 and never had a issue of screws coming loose. 500's have a lot more vibes.

Also the reason there's two separate screws is so the metal isn't fatigued when tightened plus less chance of binding. Why each part has 2 separate screws. Your way will cause stress on the part or cause slight bending of the material. There shouldn't be a reason why that screw fell out unless it wasn't properly cleaned and loctited.

If your happy with the fix kudos but Align changed the design for a reason...was to make it as less binding as possible without stressing parts.

As ualdrivr said clean the threads good with alcohol or something similar that will dry without residue and let it fully dry before applying locktite or the alcohol will break down the locktite.

[RV_7A]

I'm not trying to be rude honestly. But based on some of the comments it seems no one is familiar with this exact area of the tail. Let me explain a little better. I mentioned before the lug coming off the right tail shaft bearing housing is threaded through. The socket head screw I used screws right into those threads the same exact way the original screw did holding the upper bearing center race clamped to the lug. The remaining threads go through the lower bearing center race just like the lower original screw did. The nut and small washer clamp the center race to the lug the same as the original lower screw did. There is no binding made possible due to the width of the lug being the exact width as the space between the 2 bear races. As I mentioned before its all blue thread locked just as the 2 original small screws and their threads were. If the nut ever fell of the bottom the screw itself is tight and locktited in the lug from the top and therefore would not fall out. As for cleaning the parts before assembly I always use acetone because it is a solvent and completely removes all oil and grease. Alcohol does clean some parts well but by no means can effectively remove petroleum oil or grease products from metal or aluminum nearly as well. As for the nut I currently used I would loved to have used a locking nylon nut but I did not have one available and had to improvise so I could continue to fly. If I had to guess why the screw fell out in the first place is because I must have overlooked cleaning and locktiting it during my disassembly and reassembly when new. My fault.

I hope this makes my repair easier to understand for everyone. Sorry for the rant if it came across that way. Not my intent.

Jeff

[satsuma]

Well explained Jeff and I see where your coming from, once you have a nylon nut on there it will be a perfectly good way to do the job, being an engineer by trade I know what improvisation means

[RV_7A]

Thank You Sats. That made it all worth while explaining more clear for everyone.

Jeff

[ddj74]

I'm thinking old design but what you did makes sense but make sure the bolt and nut or nylon nut when you get one sits on the rotating part of the bearing only not on the whole bearing. Might need to get a tiny washer/spacer so it doesn't sit right on the whole exposed bearing. Then the problem you may have is the bearing will move on the machined part instead of internal part of bearing rotating causing wear. Your clearance is probably fine but i cannot tell in the pictures. I've owned the same tail upgrade for the trex 500 as soon as it came out. Probably one of the first that had it and worked perfectly and never had issues. If you need screws i have extras from my old kde tail upgrade that i'm not using since it had a bad track record with me. I've had both the pass thru bolt and the two screw tails on my trex 500 and i have to say just as far as looks i like the two screws much better then seeing a lock nut on one end.