Two full days of locked in the garage and it's just a couple tweeks away from flying.

Maiden Thanksgiving Day is just three short days away so I am full throttle attacking this.

More parts arrived Monday so with no time to waste I went to work.

First I mounted the engine so I could get the throttle servo in and start measuring for the headers and can mounts.
 

Throttle Servo set up

To get a perfect linier throttle I use a throttle arm the same length servo arm as the throttle arm on the carb. Then place the throttle at half open and the carb half open. I then make the pushrod to fit this distance. If done correctly very little programming will be necessary and hovering should be easier with the throttle control. We used a heavy duty servo on the throttle also as it will be getting a work out on a 3D flying plane under heavy vibration. The last step is to program a throttle cut and an idle up/down switch. For 3D flying this is important due to some maneuvers and the G force that can stop a low idling engine.

 

Header Installation

Next I cut the headers to length (12 1/4”) for the GP 176evo is what it calls for butttttt don’t tell anyone but I like to make them a touch longer and advance the timing a couple degrease to give a more powerful and smooth throttle transition. I use a stainless safety screw and JB Weld to keep the cans from possibly coming loose. Plane Bender Products makes an adapter for the exhaust port too match the header. GP is still a fairly new engine so header companies have not yet come out with direct fit headers.\

 

Tapping the headers for smoke

Never tap your headers closer than 4” to the engine exhaust exit. I usually tap them right at 4”-5” but sometimes a better installation is behind the flex part of the header which is what I did here. I used 8/32 nipples and again I used the trusty JB Weld to help with securing it. The header is very thin metal so getting a tight fit that will not loosen is difficult but the JB takes care of that. Someday I am going to experiment with welding my own nipples onto the headers.

 

Servo Arms and Programming

We are using 2” SWB arms. I replaced all of the recycled Chinese plastic ball links with heavy duty 4-40 ball links. First step is to get all the sub trim centered at zero or as close as possible. For the ailerons I set up the inside servo first working my way out. The Fromeco quad current meter makes this process fast. The servos cannot have tension fighting each other on them when sitting at neutral or when moving the stick. A meter helps to program a smooth travel. I programmed two rates, 3D and landing low rates. I set the expo so that the stick feels the same whichever rate the plane is on. Landing should not feel unfamiliar just because you’re on low rates but it should be smoother on the sticks for a soft landing. This is where right amount of expo can help. Each plane/pilot is different and the amount of throw will all play a factor. Having owned this plane before I set it up the same as mine was.

High rates 65% expo aileron 70% expo elevator 75% expo rudder

Low rates 50% expo aileron 40% expo elevator 60% expo rudder

As far as travel for 3D it’s usually MAX on high rate and approximately 50% of that on low rates.

 

Cooling

The previous owner was going to use the plane for IMAC only so the plane did not need extra venting for the engine. Wayne is a throw down 3D guy so we need to open the cowl up to get the air out. The only wind over the engine in a hover is the prop wind and having the air just circulates around in the cowl without exiting is a death wish. First I tape off the cowl and pencil out where I will cut the cowl. After making a dusty fiberglass mess you can see the ruff cutout. I finish the opening sanding by hand to get a smooth clean finish. 1 to 3, one part air into the cowl for three parts exiting the cowl is what we want to achieve. For Yak’s I make a beveled piece of plywood to baffle the air directly over the engine cylinder heads. I ran out of day light but tomorrow I still need to finish the cowl.

Details

Bill Paul laser cut some parts for me. A bezel to go around the DC UP and a support to go behind the canopy. This will keep the foam on the rear turtle deck from collapsing under stress from high energy maneuvers. Wayne is a Futaba guy and Bill thought it would be funny to engrave it with the wrong logo. I installed the real one.

 

Inside is complete



 

And now here is the final project ready to test run the engine.

The balance is set dead center. Not tail or nose heavy.

 

 

Wayne Bolin's 37.5% Yak 54

 

 I have not done a build thread in a while or on any of the last dozen planes I built so with Wayne’s new plane I figured it was time. Wayne’s plan is for this plane to be his “Joe Nall” Flyer. This will not be a detailed build, mostly just a fallow along install. Hope you enjoy.

Pilot RC Yak 37.5%  122" Wing Span GP 176evo MTW Headers and Pro Flow Cans

The plane came to me already built but built by a good friend of mine. The plane is stripped and inspected with only a few modification to make otherwise it was built excellent. 

First parts to install back into the plane are servos. We are using Hitec 7955^TH. We will run them at 6V using Fromeco regulators.  The previous owner used a Smart Fly Power Board but we will be using Futaba so there is no need for the Power Board. I will install the regulators where the Power board was, this should not change the balance of the plane from previous set up.

For the rudder we are using an SWB Self Adjusting Rudder Tray. Once the tray is assembled I installed it into the existing rudder tray the factory put in the fuselage. A little bit of programming and the rudder servos are set. The beauty of this tray is if one servo fails the other can still operate the rudder. With it being self-adjusting there is less strain on the servos and chance of binding.

 

I used two Fromeco 5200 Ion batteries for the receiver. Both are installed just behind the rudder tray.

I ran all the wiring along the sides above and below the wing saddle for a clean set up. The switch for the receiver is Fromeco Wolverine which is a dual battery and charge port switch. This switch is set for a failsafe ON.

 

Wayne is using a Futaba 14 channel receiver. This will give him plenty of channels including one for smoke.

The servos are installed in the wings and stabs but we are waiting for 2” SWB servo arms to get here.

The engine, fuel tank, smoke tank, spinner and numerous other parts should be arriving in a day or two. Expected maiden flight is Thanksgiving Day!

With a couple late evenings this should be no problem.

Next post will be the engine install. Since I did not install the firewall I have measured and checked the thrust angle and it appears to be right on so mounting time is cut way down and should come together quick.  I will also go into detail on the smoke system install with the new V-2 Harris Competition Smoke Pump.

Stay tuned.