r/3DprintedAircraft

The basis for this plane, which I’m calling Spectre, was the TWIST_DT platform I worked on back in May.

I originally designed TWIST_DT as a small experimental testbed for exploring different wing geometries, particularly around bell-shaped spanload concepts. It also ended up becoming a really useful aircraft for developing my understanding of fixed-wing PID tuning.

The final stage of that development was adding the two small vertical stabilisers. For me, that pretty much closed out the original TWIST_DT concept: a very small, stable and forgiving flying-wing platform that I could use to experiment with geometry, control and tuning.

Then someone who had built TWIST_DT made their own FPV version. I thought it was such a cool direction for the platform that I wanted to develop a properly integrated FPV version of my own.

So rather than just sticking a camera onto TWIST_DT, I ended up redesigning a fair amount of the aircraft around FPV. This first version of Spectre is built around the DJI O4 Wide, with support for more camera and video systems coming shortly. The wings are now removable so replacing parts in the event of crashes will be super easy which is something I'm looking forwards to the most as I push the limits of these little planes so I end up crashing a lot!

The complete aircraft is 215g AUW with the DJI video system and a 2S LiHV 1000mAh battery. It also flies happily on a 2S 750mAh, and the battery bay is deliberately fairly generous, so I expect quite a few different packs will fit. For the moment the wiring is a bit of a mess, ok for a first round of testing.

Right now I’m getting around 6 minutes on the 750mAh pack, flying it pretty dynamically through trees with loops, rolls and plenty of time on power. I haven’t actually done a proper cruise flight yet because it’s just far too tempting to keep throwing it through tree gaps.

One thing I’m really enjoying is how little ceremony there is between flights. Landing, swapping a pack and launching again takes about as much effort as it does with a quad. With some short grass, landings are extremely easy too. The aircraft can fly ridiculously slowly, and the propwash over the wing gives it a huge amount of low-speed authority, so approaches can be very slow with a lot of recovery margin available if you need to add power.

Handling-wise it's honestly verging on the divine. The original wing geometry has carried across really well, and one of the more interesting parts of the aircraft is how nicely it works together with differential thrust for yaw control. It makes for a surprisingly composed little FPV platform.

Still testing and refining it at the moment, but I’ll get some flight footage up soon!

Hi there, very interesting sub! I just wanted to show this to you to gather your thoughts.

I work in the industrial side of 3D printing as an operator and I was lucky a month or so ago to visit the facilities of HP MJF which use powder bed fusion as a technology.

As an operator of both SLS and MJF I never did push the limits of MJF that far but their team did and turns out many drone and aviation companies are using that technology because of the extremely thin walls it can produce, even light was shedding through it where the inner skeleton of the drone was visible.

They report it possible to print 0.4-0.6mm wall thickness depending on the part orientation. How do you reckon the benefits of this compared to filament 3D printing would be for light weighting?

Why it’s so cheap? Should I buy it and test it out? Will it clog my nozzle or be completely unprintable?

Currently weighs 5000g without batteries. I also plan on fiberglassing most of it so I printed it in a very weak way and didn’t really pay attention to print quality either since I’m lazy.

Designed it in blender and have been slowly printing and redesigning bits and pieces for the past few months. Plan is to run it on 8s, main issue right now is finding a good motor to spin the large 5-blade prop that I have on it currently. I have a 6374 170kv motor mounted right now but I feel like the kv is probably pretty slow for 8s especially since the propeller is a 18x14 5 blade setup

Given the scale of this aircraft, I've split the fuselage into printed sections and now moving on to the wing root. My priority is minimizing weight without compromising structural integrity. The aircraft features a 3-meter wingspan with an inverted V-tail twin-boom configuration and a wing loading of 6 kg/m². I'd welcome any suggestions for improving the wing root design given these constraints

Edit: Also the final image doesn't include the cutout from the wing root part. It was for a magnetic cover but the final image is old so it doesn't include it.

Here’s some flight footage of a bit of close-in acro around the trees with my 3D printed FPV wing.

One of the coolest things about designing aircraft for 3D printing is the amount of control you have over the actual shape of the airframe — the airfoil, twist, internal structure and how everything blends together. Once the design and tune are working properly, you can end up with a really precise little aircraft that feels properly locked in.

It’s been great getting out and flying this one a bit harder, finding more things to fly around and gradually pushing both the aircraft and my own flying.

Flown with a spotter and kept well below 35 m AGL. More info here

Specs:
600 mm wingspan
Sub-250 g AUW
LW-PLA airframe
1506 4200KV motor
4S 1100 mAh
DJI O4 Lite
INAV flight controller

It's fully 3D printed minus the wing's and wheels is there anything i should still add before i print and test it out?

Anyone with experience with this? I dont know how much is good. 3 meter wing span with an estimated AUW of 2-4 kg

I have saved a little over 500 grams off of the original design for the fuselage of this UAV project we have going on here. It's gonna have a 3 meter wing span, but the main thing I am worried about is the print cracking and breaking under the 540 gram battery because of me setting the wall loop to 1. I am at 5% infill with 2D lattice. When I give myself two wall loops the weight of just the front section goes from 112.89 g to 160g. So I am still debating if it's even worth it since I will probably just add back an extra 200 grams for the whole fuselage. Whats yalls take on this?

I am trying to print the front fuselage and I am trying to conserve strength while keeping minimum weight. I have this truss rib structure (maybe you have seen the other post), so I added modifiers to where the ribs meet the walls. My original problem was that without the modifiers the slicer wouldn't recognize the ribs all the way to the outer wall, so I just added extra walls to where I need them as seen in the picture above. Now the new problem is that I wont be printing continuously in an unbroken path. In the picture you can see how there is a cutoff from the modified rib and the walls, I want to make them connected rather than split off like that. So how do I do that? I also already tried to just boolean the ribs and the walls and then bring it to the slicer but still didn't work.