Extreme Flight 110" Yak54 - GP-123

[Joe Hunt]

Here I show where I did the same fix as on my 122" Extra. I made another slot, closer to the servo body (for less pry load). Also, you can see that EF/www.northwestrc.com includes 3 sets of truss control horns for each wing/aileron. Each have holes drilled at a different height from the hinge line to compensate for the taper in the wing/aileron. Now, if they made those holes all in the perfect places a protractor will show the same travel for each servo.

Also, a bolt would be an easier solution, but I like to see just how well the ARF manufacturer's are doing on their stock setups. Sometimes later I will cut off the trusses and drill a bolt. But, here it looks like it will be close/good. And, cutting in the new slot is definitely going to improve things.

[Joe Hunt]

I tried 4" DUBRO treadlites and decided I wanted to go a little bigger. I really wanted a 4-1/4" but DUBRO doesn't make one, so I went to the 4-1/2" DUBRO treadlites. The size looks good on the plane, the ground clearance for the spat is good, too. I did dremel a 1/4" off the bottom of the spat for good measure.

[Joe Hunt]

As for conicals, oftentimes I use a nylon locknut instead. Works the same way. Also, in various setups it helps a lot with the strength of the connection and also the lack of pressure needed to secure the balljoint... so that the ball joint moves more freely. You can see that in my rudder setup. Also the geometry I'm looking for can be seen.

[Joe Hunt]

Look how far it pivots without binding with conicals.

[Joe Hunt]

Another shot showing that if you want to use a 2" arm it's no problem, no binding.

And, I usually always use dean's ends to connect my stabs and wings. No need for a safety clip, more durable, and more throughput.

[Joe Hunt]

I'm always reading guys say you need to put a washer over the ball joint in case it pops off. Two things I think to say every time I read that. 1) I've never had a ball joint pop off the ball. 2) If you're going to put a washer on there make sure it is small enough not to cause more binding and actually help pry the joint off the ball.

Also here I show where you can use a locknut instead of a conical again. You can see that the bolt it locked in place and therefore doesn't need to be tight on the ball joint. That way the ball is not distorted and the joint has more freedom of movement. Again, always looking for less binding everywhere and of course this applies more to high rates than low rates.

[Joe Hunt]

Even though by adding a slot I have the ball joint 1/8" closer to the servo body laterally, I'm still 1/8" or more from an ideal lateral location for the control horn.

First picture shows that at mid/low rate I'm just fine. Second picture shows that I full deflection my servo arm and pushrod are too close to parallel (pry load and other dangers). Third picture shows the high rate I've chosen to be plenty for me, with the control horn being in an "okay" position, but not perfect (moved over 1/8" or more towards the servo laterally would be more ideal). Last picture shows that even pulling (far less important than pushing) I would be good with 1/8" or more laterally (the control horn position).

[Joe Hunt]

So, anyway, I've already flown one and know they're awesome planes, that's why I bought this one. What I've been talking about so far is my optimal setup. But, what I'm also noticing now is fit and finish. I'd say on par with the Aeroworks 122' Yak55 ARF I assembled last year. Meaning, about as good as it gets (and much better than other ARFs I've put together).

For instance, the wing tub fit perfectly into the right wing. Then fit perfectly through the fuse with the right wing lining up perfectly with the fuse as well (rotation pins, and both wing screws). The left wing fit on perfectly after that, with both its screws having perfect alignment. I'm nearly finished assembling and so far all fit and finish is flawless.

[Joe Hunt]

Note to self... I'm starting to like 15min epoxy better than 30min.

[Joe Hunt]