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Old Jul 05, 2014, 05:03 PM
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United States, OK, Altus
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I used black trim monokote. It has a self adhesive on the back like tape. Black electrical or packing tape would also work.
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Old Jul 05, 2014, 05:40 PM
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United States, NM, Santa Fe
Joined Nov 2009
138 Posts
Gotcha. Relative Newb to RC, only a couple years in. I found that having to stretch the wire runs down the cabin pillars has a lot to do with why you may need extensions.
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Old Jul 05, 2014, 06:57 PM
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Joined Jun 2004
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Yes. I had to use extensions on the bottom and top too. This was to allow wing removal with enough slack in the wires not to pull the extensions out of the cabin area. Excess wire is stuffed into the open wing bay. I also used color tape on the connectors to prevent mixing up the servo and flap lines. Of course, my wing has not been removed once since I finished assembly last year.
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Old Jul 05, 2014, 07:26 PM
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Joined Nov 2009
138 Posts
Rather than the weight of excess leads I thought I would just tie string to the leads temporarily, should I have to remove the wings. I may be too concerned about weight, but after looking at those small flaps and ailerons for a while, I'm really convinced that on this model especially, less is better. I don't even have the complete tail on or the motor mounted yet, and whenever I pick it up, I get the sense that it's really heavy for it's size.
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Old Jul 05, 2014, 07:52 PM
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The strings will work nicely, but you will still need some excess with the leads. This is necessary to allow removal of the wing. When the strut and screw in the CF rod is removed, the wing has to be slipped outboard enough to allow the connectors to be disconnected, or reconnected when installing the wing. For mine, I gave myself 2" between the wing root and the cabin rib to work with. I could have gone less and used hemostats, but that seemed like a little overkill.
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Old Jul 07, 2014, 06:10 PM
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United States, NM, Santa Fe
Joined Nov 2009
138 Posts
I finally got the empennage together, with one very annoying exception: My rudder installation is on hold, as my kit was missing two hinges! Since I have mostly scratchbuilt my own foamies, The one thing I DIDN'T have in my parts drawer was ACC hinges. So I must now wait for the mail order arrival of hinges. It was annoying to be so completely shut down by such minor parts. At least now I will have an assortment in my inventory (even if none of them are the same dimensions as the kit parts!).

I have also never experienced the type of construction and assembly used on the empennage, and must admit it gave me some fits. It was fussy and difficult for me, partly because my only bottle of thin ACC had thickened up enough so that I couldn't use the flow technique described in the manual to fit and glue the hinges. The elevator installation is tough to complete without getting epoxy on the aircraft and your hands. Having gone through it once, my next encounter with this style of build should be a bit easier.

I substituted a 1 1/8" tailwheel for the kit original (a rather puny specimen), and still find I have less than 1/8" clearance between ground and the pants. That is made worse by the fact that, no matter how much I tighten down the axle screws, the pants are still fee to rock fore and aft a slight bit. That has two likely possible consequences I can think of: The slack will allow the pants to rotate a bit when taking a hit, and prevent them from being ripped off, or they will be scraped and damaged. I think I need to file down the axle flats a bit to give the set screws a flatter face to sit against.
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Old Jul 08, 2014, 05:20 PM
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Just saw your mentioning loss of hinges. Check inside the wings and control surfaces. I was missing 2, one from each flap. I found 1 inside the flap when I heard a slight rattling. The other was inside the wing. Used a needle to work the one out of the flap while a shaking got the other one to fall out of the wing.
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Old Jul 08, 2014, 07:07 PM
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Joined Nov 2009
138 Posts
Thanks for the tip, though with most of the components and wiring in place at this stage, and flopping around, I doubt I could detect their presence. I also re-did the extensions, per your suggestions. I used 18" extensions on the aileron leads, and 9" on the flaps. That allows me to do the wing tuck you mentioned. Just have to make sure the bundles aren't interfering with the flap servos.

Next is motor install and some test fitting of the cowl to see if I can implement magnetic attach points instead of screws. If not, I plan to add at least two more screw attach points, to make the cowl more rigidly conform to the firewall profile.

Last thing will be windows. I would like to be able to remove at least 2, so I can use 2 hands to attach and detach the servo connections. It would be really tight to only be able to go in through the windscreen.
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Old Jul 09, 2014, 10:41 AM
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Wile awaiting the arrival of the substitutes for my missing control hinges I have started playing with motor and cowl fitting. The two elements must be manipulated together before permanently mounting either one, as the motor, in my case an Emax GT2812/10, must be placed on the firewall in a position that allows the output shaft to be centered in the cowl opening, and the distance from the cowl front must also be considered, especially if you are using a spinner.

At this stage the beautiful cowl begins to reveal it's challenges. First of all, as can easily be seen in my photo, the cowl's taper does not match that of the fuselage. Whether or not this is "scale" I don't know, but I have 40 hours of J4 Cub Coupe time, and though it might have been the ugliest version of the Cub ever produced, the wide fuselage is very similar to this model's, and I don't recall that it's cowl had a different taper than it's fuselage. While this doesn't diminish the model by much, it IS readily apparent.

The typical mismatch of the trim, oft reported, is also readily apparent. The side not visible has a better match. The changing taper of the cowl against fuselage enhances the mismatch. I will give credit where due, and must thank HH for sending me two complete rolls of covering to attempt a re-do. Of course, my generous RC-ignorant wife who gifted this to me was taken for the full ride by the HH sales folk. The model came with a full array of digital servos, an entire set of servo extensions, and they even managed to sell her a Rx...not even compatible with my gear (which I had to return). I'm surprised they didn't manage to sell her a motor. God bless her. It was still a real thrill to open the package on my anniversary and find this little red gem inside.

Another area lacking in the cowl installation is the fact that the 4 suggested screw mounts do not provide enough perimeter support of the entire cowl. My cowl collapses down below the top of the fuselage if not forced up over it for support. It borders on the impossible to align this cowl to begin with, with it's 4 puny mounting tabs. If one is required to cock it at some less-than-desirable angle to get it evenly supported, chances are excellent any misalignment is going to be even more noticeable.

I am first going to try adding some EPP foam blocks top and bottom, and see if they might support some magnetic attachments. I am thinking, the magnets buried in the foam, and an attracting piece of metal epoxied to the cowl underside. Even If I am unable to get a magnetic attachment for the entire cowl, it will still provide a couple more attachment and support points, without additional screws showing up on the cowl surface.
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Old Jul 09, 2014, 02:31 PM
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Well, I found that my Emax GT2812/10 ends up 1/2" too short to get the prop outside the nose of the cowl. I am having to add a 1/2" extension to the existing firewall. Could end up being unhappy with this motor, which also powers my 33oz Funcub. Still, with my goal of keeping the weight down on this one, to help compensate for my field elevation of 7000 MSL, things are looking good. I am getting a preliminary AUW of 42-43 oz. without battery. I am after nothing more than mild sport aerobatics and some nice landing fun.

I am also finding that when using rubber bands around the rear of the cowl to even out it's shape, it actually doesn't fit the fuselage very closely at all, unless it is forced up over the fuselage front. This is my first build with a cowl, so I'm not sure if this is the norm for models like this. The end result will certainly be a compromise in some way
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Old Jul 09, 2014, 08:40 PM
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OK, so what's the toughest part of this build so far? For me, it's definitely the cowl installation! The manual basically just tells you to line it up with the fuselage and drill the mounting holes. Right.

While constructing my motor mount extension, and fussing with trying to tape it in place on the existing mount, while, at the same time trying to jostle some kind of cowl alignment and hoping to somehow get it all centered and fitted, I simply became overwhelmed.

After some thought, I realized there were two separate things going on here: The cowl's alignment with the fuselage, and the motor's alignment with the cowl opening. Juggling both at the same time was insane!

What's job one? GETTING THE COWL ALIGNED WITH THE FUSELAGE! If you don't get that right it's going to show up big time. It's made all the more harder when you allow yourself to get caught up trying to align the cover graphics. On my model that was only going to happen on one side. I realized that I had to make my primary focus one of getting the cowl lined up with the fuselage, regardless of how the trim lined up. If the trim was off, I would just have to go back in later and deal with that.

I had discovered that because of the minor asymmetries of my particular cowl, It had to fit slightly up over the fuselage edge at the top. When I tried to get it to line up without overlapping, unsightly gaps would appear along the top, and most visible edge.

At this point I had accepted that I would go ahead and use the structural tabs and screws to get the cowl mounted. Later, I may go back in and see if I can modify the system to use magnets instead. I cut pieces of blue tape and stuck them over the fuselage where the four mounting tabs were. I then used an Exacto knife to cut the tape to match the profile of the tabs themselves, leaving the tape in place. Now I could place the cowl into position UNDER the trimmed tapes and know exactly where the areas were for me to drill into for the mounting screws. If I had just blindly used the factory dimple markers I would have missed the tabs entirely and ended up with unsightly extra holes in the cowl.

I knew I could probably align the right side graphics on my model, so I began by aligning them, and sticking that side together with blue tape, while I sighted from the side and from the top down to get the top of the cowl to match the slope of the fuselage at the nose, and to get the top-down view to line up with the rest of the fuselage. Once I had that done that I added additional tape to hold the cowl in position while I drilled the mounting holes. I used a T-pin to start each hole and then used a pin vice mounted 1/16" drill bit to drill the holes.

I now had two mounting points. I inserted the screws and the adjusted the cowl in an up-down plane to insure the slope of the cowl's top lined up with the fuselage. On the left side I had let the cowl slide under the shaped tape piece at the lower location. On the right side I now placed a large piece of tape to hold the vertical alignment while I drilled the screw mount on the opposite side. With three screws now in place, it was easy to complete the fourth.

The final result for the cowl, though lining up almost perfectly with the fuselage, leaves something to be desired regarding the line up of the graphics. I can now go in and fit my motor mount mod and adjust it to exit the cowl opening at the center before fixing it in place.

This ended up being a matter of logic. Once I realized what the proper sequence should be, it was just a matter of going through the necessary steps to completion. I will have to face the re-trim situation later.
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Old Yesterday, 12:15 PM
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United States, NM, Santa Fe
Joined Nov 2009
138 Posts
My 1/2" motor mount extension is in place and my cowl is attached, for now, with the 4 included screws. The motor shaft is slightly off center in the cowl opening, but not enough to worry about. If It flies successfully, I may later splurge on the $17 spinner.

My ACC hinges are expected to arrive today and I will then be able to get my rudder mounted and install the servo rods to the tail.

I cut pieces of hard, thick shrink wrap, slit them down the middle, and stuffed my servo extensions inside them to hide the wires in the cabin. They are easily removed if need be. I will probably use small strips cut from black packaging tape to secure them to the pillars.

I have test fitted the windows, which have a very nice fit inside the window frames, one of the more pleasant aspects of this build. I will likely use some adhesive to fix the rear panels in place, and use some kind if tape to secure the two forward windows, so as to be able to remove them to work inside the cabin.
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