Featherlight 4" 4mm

By lazd on Aug 24, 2017

28  2,395  37

Preorders are now open for Featherlight at PitchRollYaw! Buy the bundle and get the frame AT COST, or get the frame by itself at full price. All kits ship with 5 arms, and note that the final version has pressnuts instead of locknuts for easier arm changes!

4" is here to stay.

This build is literally insane. It's easily the fastest and most nimble quad I've flown, even with a GoPro on top of it. With 4mm arms and 2mm plates and a hilariously light all up weight under 250g with a 850mAh battery, or just under 280g with a 1000mAh battery, it takes a beating without breaking and handles like a rocket on rails. It's lighter than most 3" quads yet packs the punch of the fastest 4" motors and props on the market.

The combination of the BH 1407 motors and the V1S props makes it nimble, yet efficient, and the RunCam Micro Swift keeps the build light and the video quality high. I was able to put down a pretty intense 3 minute freestyle session with a GoPro on top on a 1000mAh pack. No sacrifices have to be made on this build to be light.

The XJB stack made this one of the easiest builds I've ever done. I hung it from the top plate instead of having it touch the arm screws, which means you need to unscrew 8 screws to get the top plate off, but also means it's very simple to change arms without disturbing the stack.



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Quadlite   Jun 18, 2018  

Holy hell.... Thats a really impressive dry weight for that frame. Isn't that frame over 50 grams? I built this recently https://rotorbuilds.com/build/12841 its a bit lighter, but only because its on a 23gram frame. Idk how the heck you got under 150grams with the frame you used. Your electronics must be super light! much lighter than mine. What a great build! ps: I also saw a 139mm 4 inch on here the other day. The frame was split which apparently allows it to use 4 inch props even though its very very small. It didn't look nearly as durable as yours though. It looks like youve got nice beefy/thick arms on this frame! I really like that about this frame.

lazd   Jun 18, 2018 

Yeah! This was a very early prototype with shorter arms, less motor protection, no mid plate, aluminum locknuts, and PLA cam struts, so it's about 6-8g lighter than the production frame. Featherlight 4's production weight is 46g, and I think my rebuild ended up around 170g after adding booties, LEDs, an XM+, and a few extra motor screws.

Some notes:

• Very short 16 AWG pigtail saves some grams
• XM and VTX03 are quite light, though I bet a Crossfire Nano and Unify Nano would be about the same

Featherlight 4 is about as optimized as you can get for a 4" frame, and I think we nailed the balance of weight and durability -- I only broke 1 arm on this frame; it was on an early prototype that had support for M3x16mm spaced holes, and it broke on the arm screw holes. With production versions having only support for M2x12mm motors, that break doesn't happen, and the thing is nearly indescructible unless you ram it face first into a metal gate and break the camera plates.

Quadlite   Jun 18, 2018 

Yeah im using the 2.4gram hglrc 350mw vtx on my setup. I agree 100% about the wiring. I'm definately switching to 16gauge wire too. Amp draw seems to be about 40% lower in the air than on the bench tests, so my 12gauge wire and xt60 are just wasted weight.

pjquad   Jun 13, 2018  

Hi, do you have any pics or a link to the frame set up since it doesnt come with any instructions for screw placements.. Its my first build and I could use the help. Thanks !

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pjquad   Jun 13, 2018 

Room wise, do you think you can build this thing with an F4 FC and seperate PDB board ? Want to use the CL racing F4 mini and this seperate PDB as a kinda double stack http://www.readytoflyquads.com/mini-power-pdb-20x20mm-5v-8v12v-reg-current-sensor

lazd   Jun 14, 2018 

You might be able to make it fit, but I'd go for a Omnibus Nano F3 that has a built in PDB, that'll be much nicer.

pjquad   Jun 15, 2018 

Well I can try it , if not ill go with the F3. Thanks for your reply!

DirtyDogFPV   Jan 15, 2018  

Where do you source your heat shrink from? This frame looks killer. Honestly didn't know about you until I listened to the FPV Show podcast this morning. Going to get a couple of the 4" for the upcoming racing season.

lazd   Jan 16, 2018 

The heat shrink I used on this build is 20mm diameter clear, but the best heat shrink I've seen is Insultab (3/4 inch for small stuff, or 1 inch for big stuff). It's perfectly clear and super thick when shrunk and provides a bit of protection, give it a try!

I'm stoked you came through from The FPV Show, those guys are awesome

Minichado   Oct 13, 2017  

No photo of the gopro mount?

Frame look sick. I sold my 3" and only have some 2.5" and 5", but you might convince me to give 4" a try...

lazd   Oct 18, 2017 

The GoPro Mount is up on Thingiverse: https://www.thingiverse.com/falconmultirotors/collections/featherlight

I'll get some pics posted of the mount on the frame soon!

G4Z   Oct 18, 2017  

This is awesome! I'm waiting for a CK-Lite-SR frame from Twin Quad Frames and can't wait for 4" freestyle adventures.

lazd   Oct 18, 2017 

Yeah! 4" freestyle is fun, it's less floaty, more nimble, and faster. It opens a lot of proximity options!

ukalele94   Oct 10, 2017  

Totally thinking of building this! Just wondering if a smaller angle for the FPV camera will make it almost impossible to fly due to props being in the middle of the view? Looks like if the angle is half of what it is it'll be looking straight into the props

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ukalele94   Oct 10, 2017 

Sick well if I can convince my wife to let me build a big quad I'm going with the featherlight 4! I love the style and how it can fly with that session on it. It's no 5" but it rips

ukalele94   Oct 12, 2017 

Just a question, is the 3600kv better than 3000kv on this build? On PYR they say use 3000kv for 4 inch

lazd   Oct 12, 2017 

I've been running 3600kV and it has tons of power for freestyle, but the best racers that fly 4" swear by 3000kV as 1000mAh batteries just can't keep up with long punchouts on 3600kV. So I'd go with 3000kV if you're racing or want more flight time, and 3600kV if you want an insanely powerful rig with lower flight times (2-2.5 minutes).

Jakezilla   Oct 10, 2017  

Any idea on when preorders will ship?

lazd   Oct 10, 2017 

It's looking like the week of October 16th!

Jakezilla   Oct 03, 2017  

Thing is sick!! I wanted to order a bundle from PitchRollYaw, but I couldn't find any pictures of a completed build, so thanks for posting this one!

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Jakezilla   Oct 03, 2017 

I love the fact that you are doing that. Sorry for my ignorance, are you PRY? or are you Falcon Multirotors? Or are they one in the same?

lazd   Oct 03, 2017 

I am Falcon Multirotors, and we've partnered with PRY to sell Featherlight exclusively through them. We managed to make the numbers work and I'm stoked that we can offer it so cheap!

Jakezilla   Oct 04, 2017 

Man, this is great! Thank you for contributing to the hobby and making things affordable. It really means a lot. I've been trying to plan out a build over the last couple of months, but between the costs and the rapid evolution, I couldn't bring myself to actually commit to anything. A coworker told me about the Featherlight today and I knew when I found the PRY bundle that it was a stellar performance/cost ratio. AND you have free 3D files up on Thingiverse! Text book case of 'doing it right' :)

OPIA   Oct 01, 2017  

That looks sick. The stack seems to be pretty tight though. Would an 4in1 esc fit with everthing else.

lazd   Oct 03, 2017 

You may be a little close on the battery strap, but yup, it'll fit! The bundle has an option to select the Ori or Cicada 25A 20x20mm.

Canarka   Sep 09, 2017  

Im sacrificing 1 unborn child for every day I have to wait for the release of this frame. The blood is on your hands.

Canarka   Sep 20, 2017 

Do you realize how many days it's been? How do you not feel guilty!

Matttheblindbat   Sep 03, 2017  

Absolutely love your build! I'm new to FPV Drone Racing, and Im planning for this to be my first build. What frames did you use exactly?

Thanks in advance!

lazd   Sep 07, 2017 

Hey Matt, I am FalconMultirotors.com, and this is a prototype of our latest frame, Featherlight. It's not available yet, but it will be soon!

Bushwacka FPV   Aug 29, 2017  

I bet you can get it lighter(heck much lighter) with a HLRGC FC+4 in 1 esc.

lazd   Aug 29, 2017 

So I did the 5" with an AIO FC+4in1, and it is definitely light, but not a huge amount lighter. I could go either way, and the kits will ship with the hardware to build it either way as well.

moteasa   Aug 24, 2017  

so take this over the 5" version?

lazd   Aug 24, 2017 

They're definitely two totally different beasts and it all depends on the track and your flying style. I'd say take both and then decide ;)

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