Hobbyking C-47 Build/Mods

[F106DeltaDart]

A few months ago I picked up one of these bare airframe kits from Hobbyking for pretty cheap. The model originally had a few major issues including nasty stall tendencies, wrong canopy shape, quite a few minor scale issues, and poor quality propellers. However, I really wanted a nice quality C-47, and the price and size for this airframe were perfect. I am intending to fix these issues and add some detail to the model in the process.

First order of business was fixing the canopy shape. The stock canopy has a very swept back windshield, while the real one has a much more straight mounted look. I purchased the Parkflyer plastics mod set for the canopy, and it looks much better, and they include a full interior with pilots.

Next order of business was taming the stall. Other models have a few degrees of washout built in to prevent the tip from stalling first. By adding some tip down twist in the tip, I'm hoping to get a more docile stall tendency better for slow flight. To add in this twist, I made 2 cuts of wing sections at the tip and rotated them leading/edge down across the spar. I then filled and sanded the gaps to blend the wing together. Still working on blending the sections, but it's a work in progress.

[F106DeltaDart]

Next up was the retracts. The stock gear are just a typical 90 degree electric retract with a wire strut. Fine for most airplanes but the C-47 has such distinctive gear, I had to try to replicate it.

I started with scaling a 3 view diagram to determine the proper length and spacing for each segment of the gear, as well as how it would fold. I also wanted to keep it driven by an electric retract unit for simplicity and replacability. The majority of the gear is made on brass tubing with 1/8" rod for the part that goes into the retract.

[F106DeltaDart]

Gear are almost finished now. Retracts and mounting plates are in, only thing missing is the rear mounting point for the trailing brace. However, this section of the foam also serves as a servo cover, so I have to get the ESCs, servos, and lights wired before that gets glued on. I might also look at making it screwed on so that I can remove it for maintenance if needed.

[fhhuber]

Might have to try and replicate the retracts for my Dynam C47/DC-3

[OV10]

DD............:Cool: Very impressive re-engineering and nice job on the brazing. Am interested to see how robust those giant scale pin hinges will be under landing forces.;)

[F106DeltaDart]

DD............:Cool: Very impressive re-engineering and nice job on the brazing. Am interested to see how robust those giant scale pin hinges will be under landing forces.;)

Thanks WC! I did a few bench tests on the hinges to make sure they were up to the loads, particularly in side-loading and compression. As far as I could push them, especially in tandem, they did not waver. I'm hoping that holds true when it makes its first landing.. Some high speed taxi tests will definitely be in order to test out its robustness.

FH, that would definitely be an intesting project. Some of the parts might get pretty small quickly though. Definitely post a thread if you decide to go for it!

[doctormike]

Has anyone had the patience to put the thousands of rivets on a C-47? Doc

[fhhuber]

Its been done...

Generally with a guide, mark locations and tiny dots of glue for the raised rivets

Note that its VERY easy to make the rivets too large for scale.

[ruffneckx1]

You can also use a seamstress pattern wheel. it's a little spiked wheel used to transfer a pattern to material. I've used it several times with pretty good results. Fairly easy to use. Just be aware of the pressure exerted while using it.

Woody

[rifleman_btx]

Nice!

[F106DeltaDart]

One of the other issues I wanted to correct on this kit was the nose shape. The stock nose is rather long, and a bit misshapen. With some foam trimming and sanding, I was able to get it substantially closer to the scale outline.

[Boots Whirlygig]

I wish I’d got the HK kit when it was on sale, but I was a little concerned with going off the reservation! I think the Dynam is too small, and would like to see Flightline put out a 2000mm goonie. Really I have enough projects going on and I couldn’t make up my mind on whether I’d build it as an airliner, c-47, or gunship. Then again I thought it’d be cool to make it a turboprop version, and use the motors and 5 blade props for the FMS pilatus!
im enjoying your build!

[ruffneckx1]

F106DeltadDart....................what do you plan to use for motors? The originals don't appear to be available ?

Woody

[F106DeltaDart]

F106DeltadDart....................what do you plan to use for motors? The originals don't appear to be available ?

Woody

I've been going back and forth on what motors I will use. I'm debating between 3 and 4S, which will govern the KV choice. Once I have the fuselage finished, I should be able to tell how much nose weight I'll need to get things balanced. I have some 2212 890kv T-motors laying around that might work if all goes well.

[xviper]

My original PNP HobbyKing C-47 came with 960kv motors running on 4s. Unlike the feather weight Dynam C-47, the HK one was much heavier and as equipped, was way underpowered and easily stalled if throttle wasn't kept up during the flight. If I were to do it again, I would try to put motors that would drive the props at higher speeds or choose a motor/prop combo that would give more thrust.