Gwaihir: Lightweight Digital 3" Racer

By Rose FPV on Aug 26, 2021

10  274  2

Named for Gandalf's Eagle friend, Gwaihir is built to be my most agile and reliable frame yet.

I really wanted something that could bring 5" speed to a 3" toothpick class and still have DJI vision capabilites. The problem was making a frame that could withstand such deadly crashes at the toothpick scale. (considering my flying skills, this would be tested!)
The result is my custom 3mm carbon plate with interwoven Inegra fibers. Giving maleability and form retention in the arms, which prevents shearing or critical failure on impact. Also has some dope vibration dampening properties although I have yet to really find a noticable difference. Canopy is TPU 95 at 30% infill for a great mix of strength and minimalist cover. So far with tons of flying hours ive only broken one arm and no electronics. This thing is a tank and a rocket in one!
AUW comes in at around 160g and I clocked this baby at 90mph! Be warned!

HMU if you want the files!



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Junnicutt   Aug 27, 2021  

I haven't seen Inegra used in any other frames, could you tell use anything interesting about the material? (like source, cost, weight, strength, toughness) I'm not looking for measured values just what you thought of it. Great build, I'm wanting to begin exploring racing and due to a lack of large areas to fly in I'm planning a 3 inch racer build. So this is a great example for me.

Rose FPV   Aug 27, 2021 

Sure! So I discovered and sourced the Innegra through my internship where we work with carbon composite fuselages.
Here are some technical specs:

Sourcing has to come from some more specialized distributers, which are linked to on the Innegra website,

So for this frame I have two reinforcement layers of 100% S woven prepreg fibers, layered with prepreg woven carbon. So far I have put this thing through the wringer and have been quite satisfied with the performance. They advertise impact resistance, form retention, and significant reduction in catastrophioc failure, all of which I have observed. Strength is interesting, what I've noticed is that the 3mm frame actually has an almost maleable quality to it. After many lethal crashes, I find an arm only slightly bent, after a simple bend back it flies with no reduction in performance. I imagine this can't be sustainable, but has been a fun and quite useful feature lol.
They do market it as having vibration dampening properties, I do no dispute this, but I have yet to see a vibration difference from conventional carbon frames. (This could also be my shitty frame design)
If we are talking bang for buck, the cost may not be worth the payoff. If you can get a hold of it (not easy), you would still need a wetlab and shop to manufacture and machine the plate. It really shines for fuselages and other complex bodies. It has worked quite well for me in this case, but I consider it overkill on just fpv plates until it becomes a little more accessible.

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