What hole in the servo arms and rudder, and elevator horns do you recommend for initial "beginner" setup?

From : Don Stackhouse

There's only one hole in the rudder and the elevator horn. Use the innermost hole on the servo arms. See page 4, steps 36 & 37 of the instructions, also step 50 on page 5. The easiest way to set the travels is to use the "dual rate" feature on your transmitter, assuming it has it. All but the most basic radios seem to include that feature these days.

One other thing that helps when setting up control linkages is to look at the travel you want in degrees. +/- 1/8" on the Junior's elevator is about +/- 6 degrees, and +/- 1/4" on the rudder is about +/- 10 degrees. Since the travel on most servos is typically about +/- 30 degrees, that means that theoretically you need a horn on the elevator servo about 1/5 the length of the elevator horn (6 degrees divided by 30 degrees), and the arm on the rudder horn should be about 1/3 the length of the rudder horn (10 degrees divided by 30 degrees), if you were trying to set it up with mechanical adjustments alone. That's going to be an extremely short arm on the servo, or else control horns on the tail that are so big that they almost qualify as a separate flying surface! Having dual rates on the transmitter is so much handier. If you can't program this stuff in your transmitter and you can't get the travels to match step 50's recommendations, just get them as close as you can and then don't worry about it. The Junior is a very forgiving airplane and the control throws really aren't all that critical.

If your transmitter does not have dual rates, then the primary option is to drill new holes in the servo output arms, inboard of the innermost hole that's already molded in, but far enough out that the wire will still clear the hub in the center of the arm. A 1/32" drill in a pin vise is ideal for this, but if you don't have one of those, you can just clip a short piece of the .032" wire at an angle with a pair of diagonal cutters and use that in a pin vise for a drill. The sharp "chisel" edge left by the cutters acts as the cutting edge of the drill. Because of the burr at the corners, it will cut a hole slightly bigger than the wire itself. There will be a little bit of "slop" in the fit between the hole and the pushrod coupler, but not enough to be a problem on a model in this category.

The travels listed in step 50 are approximate, so if you're just reasonably close you should be fine. Once you get familiar with the plane and you're ready to start doing loops and other aerobatics, just increase the travel to about double those amounts, as described in the "aileron" notes in step 50. That's where having dual rates on your transmitter is handy; with the flips of two switches you can change between "trainer mode" and "sport mode".

Control travel is a subjective thing. I personally tend to set up my models with extremely sensitive controls, bordering on squirrely. I compensate for that by adjusting the sticks on my transmitter to their longest possible length. The knobs on most of the better transmitters have the knurled part on the end threaded on, in an upper and a lower part that are jammed against each other to hold the setting. Some have a single knurled piece, but with a setscrew in the end to lock it in place. Loosen the screw of the upper and lower parts of the knob, screw them out as far as they will go and still have a few threads holding the knurled knob, then lock them down. Learn to hold the stick with your index finger and thumb, not just your thumb on the end of the stick. This feels weird at first, but it will give you a much better feel for where the stick is, and also allow you to make finer, more precise motions of the stick. The longer length of the stick helps with this. I learned this from flying R/C helicopters, where it was not uncommon to see 3" extensions on transmitter sticks. This combination of longer sticks, better finger technique and more control travel lets you have both fine control, and massive amounts of control authority if and when you need it.

OTOH, Joe likes to set his up with less authority and much more gentle controls. If you forced me to say which of us is the better pilot, I'd have to say (without question) Joe, so which philosophy you prefer doesn't necessarily say anything about your flying skills. It's all a matter of personal taste.

Use the recommendations in step 50 for an initial guide, but then adjust them as required to make the model behave the way that is most comfortable for you.

Don Stackhouse
DJ Aerotech