Hey this is Lee Morris from AudaciousRC, and I wanted to share some things I've learned while constructing the blunt nose versa wing, and some modifications I've made. Here's a video highlighting some of my progress (commentary is after the cinematic):
First, here's a quick rundown of the equipment I'm using:
-Futaba 14SG Tx/Rx
-1200KV 28-26 NTM with 9x6 prop
-1750 mA 4S lipo with a 1000 mA 3S lipo for the video Tx
-Boscam TS832 and RC832 Video Tx/Rx with stock antennas (will be upgrading these soon)
-HobbyKing 30A ESC 3A UBEC
-GoPro Hero 3+ Black
-Quantum DIY Goggles
-3D Printed motor mount found here: http://www.thingiverse.com/thing:175413
The Phoenix V2 is the second Versa Wing I have built, the first being a standard pusher Versa. In my multiple UDE's (Unintentional Deceleration Events) I discovered a few areas where the construction of the Versa can be improved upon. Keep in mind that these modifications add weight and may be unneccesary for advanced flyers who do not need the extra protection.
Expanding Insulation Foam
The first, and I believe most critical, modification is to fill the area inbetween the spar and the leading edge with expanding insulation foam. The particular brand which I used is called "Great Stuff". Filling this interior void with the expanding foam greatly increases the rigidity of the wing without adding too much weight. On the first Versa wing I constructed, I wasn't able to fill the entire wing because I had folded it over before laying down the expanding foam. Of course, I hit a pole in the exact spot where the foam wasn't and the leading edge partially crumpled. I repaired the area after filling the gap with foam, and when I struck another pole (I have a bad habit) there was almost no visible damage. So instead of filling the wing after I folded it, on my latest versa I layed down a few lines of the expanding foam before folding over the wing. I also did the same to the blunt nose section. Just remember: Fill before you fold.
For the leading edge, I glued two wooden dowels inside the fold, which I hope will disperse any striking forces along the entire wing. I also covered the leading edge with gorilla tape for extra strength. You may be thinking all of this is a bit much, which may be true, but if you're like me and prefer to be extremely confident in the strength of your builds, this is the way to go. Additionally, I layed two wooden spars next to the foam ones for lateral strength
Blunt Nose Section
In one of my crashes, I noticed that the sudden deceleration was making the motor mount want to lift off of the foam. Although I had removed the paper from the foam before gluing, the foam itself wasn't strong enough to withstand the forces. So I glued down a rectangle of basswood that was larger than the motor mount onto the foam, and then glued the motor mount to the basswood. This allowed the force to be applied over a larger area and prevent any crumpling or tearing in the foam. It also gave me a solid foundation on which I could lay down some of the electronics. If you have a 3d printer available to you, I would highly recommend you print up the motor mount I have linked above. It is very strong and fits the adapter plate that comes with the motor.
The blunt nose configuration is a great way to have extra space for all of your fpv equipment and electronics. However, when you cut a big flap in the top for access and placement of the electronics, you lose a lot of lateral and torsional strength. You could call this an inability to resist "flapping" forces and twisting forces. I was not able to fix this in my current build, but I am working on ideas for my next blunt nose (Phoenix V3) which will be built whenever I wreck this one beyond repair (hopefully a long ways down the road). I would recommend cutting as small a flap in the top as you are comfortable, and perhaps adding an additional spar in the midsection.
Side Note: FPV on the Cheap
The biggest barrier to most RC flyers wanting to get into fpv is cost. As a beginner to FPV, I didn't want to spend too much money on equipment, so I did some research and got some help from my friends and came up with a solution that doesn't break the bank. Here's what I got and how much it cost (on the day I wrote the article):
-Boscam TS832 Transmitter: $43.59
This transmitter comes with a built in mic, two buttons to change, channels, and is compatible with FatShark goggles if you want to upgrade in the future.
-Boscam RC832 Receiver: $33.95
2 A/V out ports and can be powered off 3S Lipo
-Quantum DIY FPV Goggles: $29.99
There is some assembly required, and although it is a rather bulky contraption, I'm quite impressed with the relative screen size. You could modify this kit yourself to make it more comfortable, I'm considering hacking some thrift store ski goggles or something a little bit more ergonomic.
-Circular Polarized Antennas: $24.95
These are an optional upgrade to the stock antennas that come with the transmitter and receiver. The circular polarization will allow you higher quality signal, and help prevent loss when banking.
The total comes to about $130, probably $145 with shipping costs included. Batteries for the ground station and transmitter will add up to an extra $15 depending on what you get.
Anyway, that's my Blunt Nose Versa Wing, and the modifications I've made to it. Comment below if you have other tips for construction, or if you have learned something new from this article!
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