I didn't know how far up or down to put the horn for my ailerons. I looked on another site and saw that they had put theirs down the whole way. Are mine too far down or just about right? Going along with all the symmetry talk, it looks right to me. The servo moves X number of degrees and so does the surface.

Ben, I used 1.25 inch servo arms, so placed the horn's center at 1" above the center of the hinge line to maintain a good ratio, and full 3D throws.

Yep, what he said THe idea is you want to keep the mechanical advantage to a fair ratio. If you want a 1-1 that's good. It all depends on your servo arm length.

You are just fine there. On all my planes I simply get the best mechanical linkage possible. Sometimes my control arm is higher or lower on the horn. For me it has depended more on the planes themselves and also servo arm length.

Ben, I used 1.25 inch servo arms, so placed the horn's center at 1" above the center of the hinge line to maintain a good ratio, and full 3D throws.




This dosent seem right to me. with this ratio you are effectivly decreasing the servo's output by 25% and increasing any play in linkage and or geartrain by the same 25%. I would never go more than a 1 to 1 ratio on servo arm to control horn. What I have found ideal for myself is to place the control horn pivot at 1.5" from hinge line and then run a 1.25" servo arm. In most cases this will give you plenty of throw for 3D while maintaining good servo advantage.


Shawn Berkheimer

R/C Blimp Productions.com

I moved it to 1" from the surface.

Well, I guess this one's been pretty well covered.

Yeah, I just had a quick question. That's what's great about RCU. If you got a question, you ask it. Of course, some of the thread Nazi's tend to ruin that.

Here's what mine look like.

Ben,
I have one inch servo arms. My plane is not set up for 3d just precision. I set the servo for 100 percent travel, then adjusted the distance from the aileron until 100% servo travel gave me 100% of my desired maximum aileron movement. These planes have a lot of aileron authority.

PS: In my opinion you don't need the black plastic nut. I screwed in a 8/32 screw, from home depot and cut the head off 170 flights no problems.

Dan

That is exactly how I have done all of my planes for the past 6 years! Leave just a thread or two sticking out of the 2 or 2 1/4" horn screw and use the 1" from the center hole on the servo arm. That way you can use maximum ATV to get the finest movement in the trims and ATV on your transmitter. I think I said that right. Instead of having to use 60% on low rate this way you can use 80% to get the same throw!!

Bobby

BEN,
Looking at your pic I noticed that your horn screw has the head part on the Possible wrong side. The screw head should be on the top on the aileron. You can put the screw in this way I guess is ok providing the screw is threaded and glued properly into the aileron. Some guys cut of the heads after they do it this way. food for thought.

I already cut the head off. I waited until I knew where to put the horn.

Ben,

You might consider geting some small washers and placing one on the topps of your ball links. That way if the rod ever slides off the ball you will still have control..They do that on full scale I do it to all my ball inks you can get a package of washers from Home Depot for pennies each.

I did my screws like yours Just cut the hrad off with a dremmel when I was satasfied with the length

Did you put some epoxy on the threads before you screwed the screw in?

If you do this the balck plastic nut is not needed I have 170 i5 minute flights on mine(over 42 hours flying time) and Have NEVER had a problem with a control linkage...I am getting ready to build a 33% 260 with BME 110 and I am doing it the same way.

Dan

I didn't put any glue because the manual didn't say to put any. It's pretty tight and I screwed the nut down to hopefully keep it that way.

Ben did it right, there's no need to screw it in from the top and this way it looks cleaner.

TF

It's easy to. All I did was cut away the covering, I didn't need to drill out the hole or anything. I figure you gotta thread the stud through anyways, why not make it look clean.