n00bs Gonna Build a Carden

[gareth.ky]

It's ready to fly.

My internet is crapping out so I can't get pics uploaded. I'll try again tomorrow.

[Spdstr280Z]

Congrats ! Looking forward to hearing the flight report !

Jason

[FlyguyXII]

congrats man!!

[gareth.ky]

OK, the Internets are co-operating tonight.

Alright, I'm kinda anal about setting up my gear. I like thing to be functional, particularly if the airplane is for contest flying. Things need to be easy to get at and and check/wrench on if something goes wrong. Of course its best is nothing goes wrong.

I went with the 2 tap system with the "T" fitting that Dan suggested. Fuel tank cap and the T came from PSP MFG. Make sure you order the ones for the 5/16" tubing and not the 1/8" tubing. Seems like the LHS and TBM only had the 1/8" version. The 32oz and larger Dubro tanks come with 5/16" tubing.

The vent and carb lines are going through a funny looking plate. That plate separates the 'wet' side where the motor is from the 'dry' side where the electronics are. Because its a rear carb motor and its going to spray backwards I did it at an angle like that. If I had done a standard can tunnel it would have put the carb in the 'dry' are. The plate is attached with 4 really strong magnets so its easy to gain access to the throttle servo for maintenance. Rubber grommets to make sure the fuel tube isn't rubbing on anyhting.

The fuel dot is from Jersey Moddler. It's BIG, its red, its got dry break fittings. I got their fuel can too with the same fittings which is nice. I'm going to be hauling this gas can around in a small car so this choice was mainly utilitarian. The can has a neat probe to capture the overflow from the vent line while you fuel up. It stows back inside the can when not in use. I'm looking forward to seeing how this works out.

The tail wheel got rigged up with some compression springs. You can get them from Carden, I got them somewhere else I can't remember. I couldn't use the tiller because of how far back the wheel is mounted. The rudder linkage with carbon tubes and rod ends glued with JB Weld. I did something similar on the throttle servo rod. The tail wheel looks bad ass!

I used the socket servo screws and replaced the servo arm mounting screw with a socket version as well. All the servos were mounted and then un-mounted and some thin CA was piped into the holes and then they were mounted back again. All connections use nylon lock nuts. I prefer the lock nuts to thread locker in general, it's something I can see failing.

I used the socket servo screws and replaced the servo arm mounting screw with a socket version as well. All the servos were mounted and then un-mounted and some thin CA was piped into the holes and then they were mounted back again. All connections use nylon lock nuts. I prefer the lock nuts to thread locker in general, it's something I can see failing. Throws are set up for precision. I'm in on the closest hole for the ailerons and the third closest hole for the elevators.

[gareth.ky]

I got the X9303 for guidance and it's set up for 3 flight modes (one of the major reasons I upgraded from the DX7).

The flight mode switch on the Aircraft version is in an awkward place. JR Radios: Ergonomics Optional. I moved it, some soldering of small wires is required. Luckily there was a free ground pad on the little circuit board there. I've discovered that if you get the Heli version the Flight Mode switch is where I put mine. I stuck with the Spektrum technology on this one because it has the Model Match feature. Futaba still has the nicer Tx unit and better ergonomics, I so wanted a 10CAP.

I didn't have a tube to run the servo wire back to the tail so I improvised something. I used a very light balsa stick and some Velcro tie wraps, total weight is 6 grams (0.2oz), 1/2 of that is the Velcro. This looks neat and it holds the wire to the airframe so it takes the strain load off of both ends. All three wires are also zip-tied together every few inches to its all tidy. It's going to be a a PITA to change the rudder servo so lets hope that doesn't happen too soon.

The funny plastic things keep the elevator leads from falling back inside the fuse. I'll have the stabs off to transport it so this is important in my situation.

The Rx main unit is on a lightened frame that you can see through the hole in the floor of the cockpit. Its easy to get at the ports to attach servos. I hate it when the Rx is hard to get to.

The 3 satellites are mounted so as to give good signal in most orientations. One goes at the crown of the turtle deck and is oriented parallel with the wings to hopefully give good reception when the airplane is heading straight at you. Its high enough that it can 'see' around the motor and fuel tank. One is on the floor parallel to the fuse, you can hit this one in a hover or any sort of vertical orientation. One is on the fuse side oriented vertically and it should get best reception with the airplane flying straight and level.

[RTK]

Nothing anal about a nice clean set-up

[gareth.ky]

Power is provided by two 2300mah A123 packs that I built from a Dewalt 36v drill battery. Johnny Chimpo Brand Each pack has 16 gauge wire (Tower sells it) and connects to a Kodiak switch. From there prower goes over 16 gauge wire to the Rx. The right side switch also has a lead that powers the ignition. So one switch turns on the radio and the other turns on both the radio and the ignition. Because the Rx is visible its easy to see before takeoff if both switches are on, even if you cant see both sides of the airplane easily. I'll keep a close eye on how the packs drain and report back on the setup. Even of the right side pack drains faster than the left the failure mode is at worst a dead stick.

The battery packs had to be mounted out on the motor box. Its just where they had to be for balance. They had to be low down like that so the cowl would go on in 1 piece. I'm a little worried about all the weight in the airplane being so low down. The inverted engine, canister and batteries are all below the thrust line. I'll just have to wait and see how that works out.

The Rx, satellites, ignition and battery packs are all mounted on industrial velcro padded with foam rubber. The radio gear has masking tape on it so you don't have to glue directly to the gear. It's and idea I got from one of Quique's ARF manuals.

An I have photos I don't have comments for:

That's the CF tail tube. thw dowels are glued in the ends and then you drill into them for the mounting screws. Walt recommended that one.

The manual choke. Its got fuel tubing on it so it doesn't rattle around.

Final weight of the fuse is 19 pounds 7oz. which means the final dry weight is about 25.7 pounds. I can drop 4oz with a carbon wing tube and maybe 1/2 a pound if I do something with the landing gear. For now though I'm really happy with that weight.

[gareth.ky]

This thing has more blue glowy bits than my computer!

[TrojanMan]

Nice job Gareth!
I knew you could get it done!
Now for some test flights before the Tulsa Heatwave?!

[gareth.ky]

Yup its time to run some gallons through this thing.

You going flying this weekend?

[TrojanMan]

Yep! Let me know where and I'll be there.

[gareth.ky]

Wind for Saturday is supposed to be ~16 mph all day.

Too bad I don't have time to fly tonight. It's going to fall under 10!

I'' be flying it either at Guthrie or West Side. Guthrie is less crowded and has less stuff in the way of a dead stick.

[gareth.ky]

Wayne helped me discover a fatal flaw in my tail wheel setup:

YouTube - Tail Wheel Spring Geometry Issue

Going to try a whole different setup tonight.

[gareth.ky]

If anyone knows of some place, any place, that sells really tiny pulleys let me know. Like something you would see on a model sailboat.

[SunDevilPilot1]

Here is what I did.....

It may help you if you have some extra holes in your rudder servo arm about the same spacing as the tailwheel tiller.

On mine the innermost cables on the servo are going directly to the tailwheel. The outermost, on the offset bellcrank are going to the rudder. Both run through the same tubing.

In your case you could just hook the servo arm to the tailwheel tiller while utilizing the springs as a "servo saver".

Just a thought,

SunDevilPilot