Incident with ARF Nobler

This was passed on to me by a clubmember - I don't know if it's happened to anyone else but it warrants some caution.
Bob Z

Subject: ARF Nobler

Bob
Just a little heads up to anyone using the supplied clevises that come with the kit. I had the pin pull out of the elevator horn on the second flight. Damage was both mounts broke through the rear boltholes and busted the cowl a bit. I replaced the mounts and installed a new #489 Brodak tank. I drilled out the elevator horn and clevis and soldered in a 3/32 music wire pin. The plane flies well with an FP40, 11/5 APC prop, 60ft, 8 in lines. I hope this helps someone out.
George.

The one to use is the Gold Sullivan with the little clip. Never had or heard of one failing as long as you put a jam nut on the rod to keep the threaded end from self destructing due to vibration.

Bob,

You are going to catch heck for this! I remember the last time this subject came up!

One way to help with vibration is to flood the clevis threaded area with the blue locktite. This is some sort of plastic which flows into the threaded area, and (I believe!) absorbs the vibration, which could "eat" away at the threads.

I interpret this event here as the pin itself pulling out, not the entire clevis off the pushrod (I am not sure if this is the correct interpretation). If so, I wonder if the person involved used the piece of fuel tubing (included with the ARF) which slides over the clevis and holds it tight.

Just re-read the post and it does sound like he forgot the little plastic keeper or didn't get it on far enough.

Just remembered I used the stock clevis at the elevator horn on my ARF Nobler and Gold Sullivan's at the flaps. Used the stock clevis because it is soldered on and was the easiest solder type to get to at the time. So far so good and it has had many flights in 15 to 20 MPH wind, when the wind blows I break out the Nobler because it's fun, just been lucky I guess.

Bob,
Thanks for reminding me that I too soldered on the elevator clevis. On the other hand, it probably would be a good idea to make a little window under the elevator to be able to occasionally look at the linkage, just to be sure that the tubing is still hanging in there!

Actually since this also reminded me that the stock clevis is metal, it also is possible that the pin really did break off and fall out. Another argument to put my window in!

>> I had the pin pull out of the elevator horn

Sounds like it popped out of the horn but you are right, hard to tell from the post.

I had to get inside my nobler and remove the control rod to compensate for an incidence problem, the result is a hole in the side of the fuselage under the stab covered with $cote.

Not only was I dumb enough not to check the incidences, I CA'd the threads on the clevis at the flap horn. The only option was get the control rod out and soak the threads in acetone. Now the elevator hangs down a few degrees when the flaps are level but it flys fine.

The pin on the clevis broke on mine also, but on the elevator clevis that hooks up to the flaps horn. I went to check my controls before takeoff and no elevator. I caught it right in time. I put new ones on and soldered all of them and cut out the back so I could solder that one to.
Ryan

>This was passed on to me by a clubmember - I don't know if
>it's happened to anyone else but it warrants some caution.
>Bob Z
>
>Subject: ARF Nobler
>
>Bob
>Just a little heads up to anyone using the supplied clevises
>that come with the kit. I had the pin pull out of the
>elevator horn on the second flight. Damage was both mounts
>broke through the rear boltholes and busted the cowl a bit.
>I replaced the mounts and installed a new #489 Brodak tank.
>I drilled out the elevator horn and clevis and soldered in a
>3/32 music wire pin. The plane flies well with an FP40, 11/5
>APC prop, 60ft, 8 in lines. I hope this helps someone out.
>George.

Another one bites the dust.

It's been stated over and over, but I guess, not enough. Commercial R/C clevises *are not* stout enough for using in C/L stunt planes, no matter how big or how tough they are. They *will* eventually give up the ghost, there is simply no doubt about it. I've seen at leat 10 airplanes wiped out by them, and know of at least 20 more.

Ball links = = OK.

R/C Clevises = certainly going to fail.