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Cox/Pica Duallist

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Old 02-03-2010, 05:57 PM
  #1
Montague
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Default Cox/Pica Duallist

I'm working on the Cox ARF version of the Duallist (as Cox called it, vs. Duellist per Platt/Pica)

Can anyway, can anyone out there who has flown this model tell me what they did with the vertical stab and rudder? the way the ARF instructions say to do things looks silly, with the tail post sitting behind the back of the fuse, and the post and rudder not even reaching the bottom of the fuse.

I'm cutting up the back of the fuse a bit to move the stab forward and get the tail post inside the fuse, then I'm going to lengthen the bottom of the rudder a little to make it come out flush with the bottom of the fuse. At least that's the plan so far, and I'm curious what other guys have done.
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Old 02-03-2010, 06:00 PM
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Default RE: Cox/Pica Duallist

I forgot, I'm also curious if anyone has had any problems with the pushrods flexing and getting flutter on the elevators or rudder? I hate the solid metal rod in a plastic tube style pushrod, but it looked like a ton of work to get inside the fuse and make room for some nice fiberglass/CF rod pushrods. In particular, the unsupported distance from the end of the tubes to the servo arms looks quite long to my eye, so I'm wondering if I'm saving time now only to spend more time later?
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Old 02-03-2010, 07:17 PM
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Default RE: Cox/Pica Duallist

I would go with the carbon fiber/fiberglass pushrods. I have Dave Brown rods in my Duelist (not the ARF version) and they work great.

I didn't even know that Cox finally released this plane.

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Old 02-04-2010, 10:29 AM
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Default RE: Cox/Pica Duallist

Yes, those are the types of pushrods I normall prefer, and have in several models. I often use a 4-40 rod and keep the rod section very short, espeically on the servo end, sometimes just enough to clear the servo body or mounting.

But as I said, I don't really want to tear up the plane unless I have to. The ARF has bulkheads blocking most of the space inside the fuse to support the guide tubes they have installed. Good for the tubes, bad for running conventional pushrods. I'd have to cut the whole bottom off of the fuse, cut up the internal formers, re-brace the bottoms of the formers, put the bottom of the fuse back together, sand, and re-cover. It's not that hard, of course. But it's several days worth of work for my limited shop time, so unless it's necessary, I want to avoid it.

I think I'm going to try the stock pushrods, flight test carefully, and see if I need to change later.

If this were a kit and not the ARF, there wouldn't be a question of what I'd do, but it's not the kit.
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Old 02-12-2010, 10:21 PM
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Default RE: Cox/Pica Duallist

My Dad assembled mine for me as he needed something to do for the Winter. I have the stock pushrod set up and have had no problems. I know he threaten to pay me for the airplane just so he could burn it a few times. He assembled their T-28 and had a lot of confusion/problems with that tail assy. also. Hang in there.
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Old 07-14-2010, 03:42 PM
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Default RE: Cox/Pica Duallist

Finally, here's mine:

Engines are OS .55AX. I cut open the bottom of the fuse by cutting ovals out of the thick balsa bottom between the formers, and then cut out the plastic tubes and opened the formers to make room for fiberglass pushrods. I have a Y rod on the elevators and a straight pushrod on the rudder, and it seems to work great so far. Still trimming the plane out.

On the fourth flight, I had a bit of a dummy moment. One throttle servo failed, and stuck the engine at full throttle (or pretty close to full). Somehow, while trying to sort that out on final (when I realized one engine was running way too fast), some reflexes kicked in, or something happened, and the other engine died while I was approaching the runway, fairly low and slow. So I had one engine stuck at full throttle, and one engine not running at all. I was quite surprised at how well this plane flys on just one engine, I was able to keep the plane in the air, and climb up and wait for the stuck engine to run out of fuel and fly a normal deadstick landing. To add to the bad luck, the nosewheel didn't lock down fully, and on landing a muffler hit the ground causing some minor damage to the firewall, but that was easily repaired in one evening.

The plane is slower than I thought it would be, but still flys well, and is fun to goof off with.

I now have a rudder to throttle mix that allows me to do a "cartwheel" 540degree hammerhead, which isn't something you see every day. It also does some very flat flat spins

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Old 07-20-2010, 10:03 AM
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Default RE: Cox/Pica Duallist

The Duellist is one of my favorites. Awesome [link=http://www.youtube.com/watch?v=tX1NozLIGqs]flat spins![/link]
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