So I have been researching on the YA15 ARF, I dont want to ask questions that can be answered easily through a search function. At this time I have only come across 2 pictures of the elevator/rudder box assembly. Its mainly the geometry of the elev servo/pushrod that I am concerned about. I am using 8711's with titanium rods and monster ball links on both sides and want to see what you think of this angle between the servo arm and elevator arm. This picture is with the servo mounted in the mounting slot. The gromets and rubbers are not installed on the servo so the height is 1/4" less.

Did you guys remove the eclip and slide the elevator horn/shaft out of th bearing to work on it?

What do you guys think?

Thanks, Pete

you have two options here .. one would be to put some hardwood blocks under the servo mounts, shifting it more in line with the elevator horn. Glue the blocks down, however also use longer screws to also penetrate the original servo mount wood.

the other would be to use a heavy duty ( aluminum) servo horn, and run ball links on both ends , that angle would be insignificant as to load

by the look of it , the elevator horn can also be flipped the other way bringing the horns a little closer to being in the same plane ( no pun intended )



~V~

Hi,

No, don't pull the e-clip. I'll see if I can send you some pics. The blocks I mentioned in the PM or other thread are a good idea, and they do end up bringing your linkage in line more. That having been said, the plane has been flown plenty just like that. Since you've got ball linkages on both sides, it works, but straighter is always better.

Hi,

Here are a couple of pics of different installs with the blocks...

Pete,

First thing I would also do is throw away that connector you have on the bottom of the picture. I know many have probably used them, but I have one that broke on a plane and glad it was not during flight.

Ralph

Ralph, I did not intend to use that connector, I was using it to get an idea of the rod length.

Shaun, If you dont mind clarifying, When you say straighter is better... Are you reffering to simple rules of force distribution and geometry? Or something else?

I need to have 0 play in this system or I cannot sleep. If a non-straight connection will have any play AT ALL I will use the blocks.

Thanks, Pete

Pete,

I'm talking about simple rules. I've had about 15 of these things over the years, and several different setups depending on where I got it or who put it together. The ones I've built myself are all pretty much built the same way, and that's with the blocks. Re the connector, I can't speak to Ralph's experience, but I can tell you that those are on every single one of mine, including the ones that have flown on P-160s and K-170s. They're fine.

Pete, get some sleeping pills. Your are always going to have a small amount of play. The tolerances for ball links are not that tight and the gear train slop in the servo all add up. You can expect to see from 1/16" to 1/8" play in your stabs. Relax you wont notice it while flying. The F-15 is not a fast jet as it has it lot of intake drag. The geometry of the stabs magnify the small amount of play in the linkage. The YA jet is a very nice kit and flyer. Have fun. Dealing with Shaun is always a pleasure.

Yes Shaun has been great!

Tom, I used monster ball links with thin CA on my SM F-18 and I did not notice any play. Either manipulating the finished pushrod (Ball links installed on both ends) with my hands or in place, I still did not get any play. Only from the 8711 geartrain. I guess I will just get going and see what happens. Im sure you know better than me and I have only heard great things about this jet but I just cant deal with play on the stabs. Sleeping pills wont help either .

If for some reason there is play with this setup I will go for the blocks with a clevis on the servo side.

Pete

Pete,

What's the thin CA for? Anyway, if for any reason, you're unable to eliminate all of the play/slop, bear this in mind: Those stabs are designed to be dynamically stabilized, and they are. I'm sure that I've had this airplane as fast as anyone ever has, and the stabs are rock-solid throughout. On mine, I tolerate as much as 1/8" at the L.E. without any concern.

Tom.

Thanks!

Scotch?

Scotch?

Well, guess that makes it a double!

Shaun I have found that thin CA eliminates the play between the ball and plastic housing it sits in. I know it kind of sounds rediculous but it seems to work.

Hi,

I'm guessing you mean glue on one side and the other side is lubed? If not, how does the swivel function of the ball link work?

I drop it over the ball Shaun. The swivel function is retained as the CA breaks free from the metal, only adhering to the plastic. I guess tightening the seal. I remember laughing to myself the first time I heard it but then I tried it.

Hi,

Wow, well when I accidentally get one little molecule of CA into a hinge or link, it ruins it! I guess I might try that, but I'd definitely lube the ball with oil first. I use the snap-on type heavy-duty ball links from the RC-Car side of the hobby shop, and those balls are flat on top sometimes, so I would be worried about using them there...

shaun,
The thin CA trick is something heli guy's use allot. you put a very small drop of thin CA on the ball, and then keep swiveling the ball link around the ball so it transfers the CA all over the ball link, and keeps it from getting glued shut. It works great!

I'm fitting my retracts as we speak and it looks like I'm going to have to do a lot of grinding. They are anodized red. I'm wondering since I have tams tires. Just want to make sure I have the right ones.

I'm using my phone and don't hace access to a laptop right now. I can't post a picture.

Thanks