Hi Chris, I'm a big fan of the work your doing and recently purchased this frame from a UK vendor (not going to name them publicly). I have been very disappointed by the quality of the frame with one of the camera plates missing, undersized holes in the bottom "X" plate, the "X" plate and arm braces have also been countersunk but supplied with domed bolts (i.e. weaker than need to be). In addition to bolts missing from the pack there were an additional 18 "cheese head" bolts and an additional aluminium spacer supplied. There were no instructions, parts list or branding on the frame, other than a made in Canada label. I live near Royston and am happy to show you the frame if you want to inspect it or can supply photos. The vendor is reputable and I've used them regularly with no quality issues.
This looks awesome. The only problem I have is that my old school 3" with 1407 3600kv is still so incredibly much fun. What it lacks in smoothness it makes up in speed, perfect for flying like a madman after a stressful day.
@@ChrisRosser i have question. By your graph, transtec beetle 2.5 inch quad at 250gm should perform at red/orange line. But how is that in Joshua Bardwell's video on that quad, when Vanover flies it, it almost /fully performs like a 5 inch freestyle or blue line? Which to achieve at 250gm should have used 3.25 inch props?
@@AfafPrinceOSH I mean it just doesn't perform like a 5". Not even close. Vanover is a great pilot and he flies it well to be sure, but have you seen what he can do with a 5" quad? I have a GepRC Rocket Lite with 2.3" props which is pretty similar disc loading and you can freestyle it but you would never think that it flies like a 5". It has much less power, speed and acceleration and much worse propwash handling. A great pilot can fly around those limitations and that is what Vanover is doing.
The babyhawk 2 has a very tough frame. I have yet to break any part of the frame. But your frame dose do a 1up on the motor guards on the arms. Babyhawk dosnt have this and that’s the weak point on it. Motor bells/shafts bend very easily. So I’m sold. Orders in for a 3.5 and 5.5. Thanks for all the hard work on your frames.
Hello Chris I thought the 4mm arms on the AOS 3.5 are tough but it broke after a crash onto the grass from 30+ feet. I suggest everyone get a replacement arm when they order an AOS 3.5 frame. It is a pain to buy a $6 replacement arm when the shipping costs = $19. I build two AOS 3.5 with identical electronics and the only difference is the motor - one with Xing2 1404 (240AUW) and the other BrotherHobby 1504.5 (248AUW). I can tell you that the frame with BrotherHobby motors is way more fun to fly than the Xing2. The Xing2 just lacks power and this lack of power is especially true when coming out of dives.
Hi David, sorry to hear you had a crash and broke an arm. If you could reach out to me on email and send an image of the damage that would be very helpful. AOS 3.5 is coming to Banggood soon to help with shipping costs for international pilots.
Hi Chriss, I was thinking of pulling the trigger on a Babyhawk. But building myself just seems like more overall enjoyment. Just double checking if a few changes to parts make sense (based on what I can get). I'm happy to take a few extra grams. - Vista + polar - Betafpv 1505 3600kv - Diatone Mamba F722 Mini - Crossfire Nanno
@@ChrisRosser thanks a bunch mate. Btw, I just finished tuning a th2 freestyle with your methods. Never flew so good! Next up the "work" betafpv 85x cine whoop.
Hey Still It, get the AOS 3.5, you won't regret it. My build is about 250g with an AIO board, 1404 motors and Vista/Nebula pro on light 850mah lipos. You can stay well below 250g with 650mah batteries. Here's how mine flies: ruclips.net/video/EQNW_taSa7Q/видео.html
Love this video! So much thought has gone into the design Would be cool to show off your quads on a plain workbench so we can better see the beauty 😍😍 thanks for what you're bringing to the hobby!
Thank u again for all the inf. u have giving us i feel that some of that inf we can use in other frames as well and that the beauty on sharing the knowledge.
Fantastic. Thanks for your support. I hope you have a lot of fun ripping the little guy around! I've been surprised by how much fun it is to fly. I always take it out with me even when going to fly my 5inch quads.
@@ChrisRosser I have been searching specifically for this size and weight class, since I'm so in love with my TP3, but sometimes want a bit more weight and punch. BTW, what are your thoughts on motor sizes and kv for 4S? I'm considering 1506/1606/2004 since they have similar stator volume 🤷🏻♂️ Also, could I fit 1300 mAh 4S packs on here?
@@MartialArtsDKdotcom I would probably go for a 1505 with an 850mAh 4S. Otherwise you'll find that you move away from the optimum weight to prop size ratio.
@@ChrisRosser Yep, maybe with a naked GoPro for better HD. And the AOS-5 is built, fine tuned and fantastic. Full build and tune video is on the way. The frame design, particularly the arm design makes tuning so much easier. 7 inch in the planning?
I hope you enjoy it. My AOS 3.5 really surprised me. I originally thought: "Yeah this'll be OK for sub250g but I'd always prefer a 5inch". But the first time I flew it I really fell in love with the little guy and I fly it all the time now!
This looks like a great build mate 👍😎 Perfect for running without a HD cam IMO, quite often I use the dji goggle DVR to upload, looks pretty good. BTW I’ve been using those little sigma antennas for quite a while and really like them, so light and seem to work just as well as the caddx antenna and they are surprisingly durable given how flimsy they feel in the hand.
Just got my 5.5 last night, Put it together and it's lovely. saw the 3.5 on the site last night while building and instantly added to cart. just need some motors...
I own the frame as well and I'm quite pleased withe the quality and rigidity, unfortunately the runcam hybrid camera will not proper fit, which was actually my plan to fit in all along.
i just got this frame now. seems the camera plate design has change with regards to the mounting holes for screws. theres quite a lot of mounting possibilities with the new camera plate . I am also planning to go for the runcam hybrid, and your experience starts to doubt me too. funny thing is my fc is whoop type.
i recently got a crux35, im already on my second bottom plate lol, i do like the idea of replaceble arms, but i come in at around 190 grams with that same 850mah battery but the stock xt30 version with smaller cables, added vfly self powered beeper with gps passthrough (because thats the only one i could get from where i was making a larger order) and the stock motors although i just ordered these exact motors for my super crux35 build im making where i am going to stick 2 bottom plates together so its 6mm thick, because the bottom plate is only 13.5 grams so i think its a good trade off for durability, and i can put on a smo4k on it, upgraded vtx and aio fc, and still be under 250 grams. the resonance thing would be interesting to me with the crux frame, it flies just so dam good i cant imagine being single bottom plate could be very detromental on such small arms, espesually when i do my super crux 6mm thick boii
From the pov of academic discussion; I think it gets a little bit tricky looking too hard at the disc area graph at the lighter end of the spectrum. There are other factors which suddenly increase/decrease in importance relative to bigger quads. Prop blade volume/inertia, relative weight of electronics to motor size and frame weight etc. All the compromises become more important. It's not a bad place to start but optimising micro setups is tricky and requires quite a bit of trial and error.
I've found that prop tip speed and disc loading is the correct first order analysis approach even for quite small drones. There are of course second order effects to take into account such as prop pitch and blade count and motor sizing. These follow on naturally from a consideration of flying style and necessary motor torque for the chosen prop. I'm hoping that applying these rules in sequence can reduce trial and error! The most difficult thing is calculating what a particular build will weigh before you build it 🤣
@@ChrisRosser the factors I'm talking about here relate to the compromises that put a quad on one of those lines. For example motor torque. You may be able to say ok from 5"->4" the disc area is 16/25 so the motor should be 16/25 of the size. At smaller scales when you do this you add more weight than you should because the electronics which were negligible take a larger percentage of the mass. So if you want to stay on that same line you might need 12th/25 of the motor volume to hit the target weight. Same with frame strength. Effectively you have these "steps" which relate to the weight of electronics amongst other things. A whoop needs 8-10g of electronics, go up to a 3s 3" and it's 15-20g, go down to 2.5" and it's STILL 15-20g because you need the same electronics.
@@frasersteen Absolutely right. 100%. For small quads you cannot hit the same disc loadings as you can for 5". That doesn't mean the lines are wrong just that we have to settle for what we can achieve. The disc loading lines still allow you to compare your build with quads of different sizes to determine roughly how it will feel to fly *assuming that the max prop tip speeds of the rigs are comparable* which can be tricky to achieve for small quads as well.
hi chris, I've finally received the frame from CNC Drones, and there's something I'm not sure you're aware of. I bought the countersunk version, and while the long hex-head screws which mount in the bottom use the standard 1.5mm hex key (which is part of EVERY FPV toolkit on the market), the short screws used on the top plate in the same standoffs use the 1.3mm hex key. maybe it's asking too much, but I think those should be changed, so you can use (and carry around ) the same hex key driver to work on both. also, if I may suggest an improvement, you could add a cut-out on the lower X piece which retains the arms, so you can access the rear-most screw for a flight controller like the iFlight Beast .thanks!
Funny enough I just upgraded my babyhawk II HD with an iflight F7 beast and was looking for a 3.5 inch frame to replace the not great emax frame and this pops in my feed! Looks like my AOS5 is getting a baby brother :)
@@ChrisRosser I'm sure it will be great if it handles anything like its' older brother :D Completely agree with your sentiment on sub 250. I always thought that when I went to 5inch that I'd never look back, but with 3.5 at just under 250 you get something that you can toss and carries its momentum well but also turns on a dime if you want it to, it's great!
Poking antenna out of the front top plate, feels more optimized for return, which is what you want. It can give in a crash but is fairly fixed in place. The signal is absolutely horrible with the antenna mounted on the arms. Running 6s skystars AM42 stack. HDZero freestyle VTX fits in front if you remove the standoffs and replace arms screws with 2mm nut and screw.
indipendente arms great, although on these small and light quads, it's probably easier to just beef up the frame a bit and make it nearly unbreakable, weight you save by not using extra screws can be used somewhere else on the arms... i flew micros for few years and haven't broken single arm...
A few people have reported cracking their bottom plates on their micros and being very frustrated (having to rebuild the whole quad) so it is a problem for some people. Replaceable arms also improve vibration and resonance performance over unibody frames.
I've two quads with this great frame! But I wish it was possible to buy more spare parts. Not only an arm but the camera mount also. I've one very damaged camera mount that I soon need to replace.
Hi Chris, did you get the ELRS ceramic receiver installed? I'm curious how it does being placed between the vista and FC. Great content as always and I appreciate your time, hard work, and dedication you have for the hobby...
On the topic of the AIO's with Blackbox, I can recommend a fairly cheap and quite good option - JHEMCU GHF405AIO Pro - only the Pro version though, I have a couple of 45A ones and they are great, especially for the price. Not that great at overclocking though probably due to BGA bare die, do not even try 240mhz on this one, you'll reboot in the sky :) 192mhz definitely works, 216mhz YMMV :)
I'd like to hear too! Actually, Chris explains drawbacks of props bigger than 3.5 in the sub250 category in his video "Choosing the right prop diameter...". However I fly 2fiddy with 2005s at 248g AUW with bi-blade props and 720mah 4S. I have no complains so far :) it's great! Maybe after all it's just a question of feeling/personal preference. I admit staying under 250 is a bit tricky in 5", for example my vista is de-cased. I might try a 3.5 to see the difference.
ive just finished this build but with slightly different electronics but with chris recommendations, i advice all you just use the iflight beast if your going for the aio whoop as my cheaper jhemcu whoop board have problems with blocked usb ports with the standoff, as the usb port is located 2mm to the left side (unlike iflight) i end up removing this standoff for the time being while i tune it.
The only part that gets me about that frame is the lack of the antenna mount. Especially since that can be a big source of vibration. Definitely needs a properly mounted vtx antenna for best signal and least amount of vibration. Same thing with kabab’s tooth fairy frame!🤔
Vtx mounts are tricky. I cable tie my antenna to the arm and that works great with DJI. If you're on analogue then it's more of a tradeoff. A stiff mount will add significant weight and a flexible mount is bad news for vibration.
This is awesome. I swear I was just thinking the other day that I wish you could shrink your 5" design down to 3.5" lol. I've been wanting to try a 3.5" quad since the Babyhawk 2 came out but that one had a few things I didn't like. This design ticks all of the boxes for me. I'm gonna go with a naked vista/nebula pro and BetaFPV 1505 3600kv motors. Can't wait!
@@ChrisRosser I think I'm going to use a JHEMCU 35A AIO 20x20 that I have laying around. It's an F405 with 4 UARTs and black box, plus a 9v 2A power supply for the vista. Pretty sure the naked vista will stack on top of that without having to even use the second bay in the frame. I don't care that much about the 250g weight but it should be pretty close to that I think.
I don't think so. It's a pretty tight fit for 3.5s. All of my frames are pretty optimized for a particular setup so there ends up being less flexibility as a tradeoff.
Would have bought this as it looks like a great 3.5 I've been looking for but $22 for shipping to UK and possible import charges just too much. Shame you don't sell through the main UK shops like unmannedtechshop or hobbyrc.
Hey Chris nice design, can you fit a full size DJI HD camera unit with the built in DVR in this frame or is it only able to take the vista. I like how your frame doesn't show props in view unlike the geprc smart 35 HD, but in all fairness the geprc smart 35 frame does comes with four independent front and back brace arms for reinforcement as well but you have to put those on your self. I do have a question regarding the back brace, aside from symmetry and looks what's purpose does it serve unless your flying backwards all the time, wouldn't it save some weight if you lose the back brace. Doesn't all that reinforcement obstruct the wind flow from the props and can possibly cause snagging in the trees. I mean you have the vista unit siting in back it's already tail heavy, one of the things I did like about the geprc smart 35 is it has all the component in the center so it's very well balanced. I do like the horn tips for protecting the motors I believe Tommy Tibajia was the originator who came up with that. From my research alot of pilots been saying that the 1404 motors being used for the 3.5" are under power and the ideal size motors for this size quad would be a 1804, 1806 with 4,000KV +/- but I guess that would probably be tricky to get it under 250g.
You can fit the DJI camera in it with the Vista. The Air unit doesn't fit I'm afraid. The braces are not only for strength they also improve the resonance performance of the frame. I think the main benefit of the AOS3.5 over the Smart35 is the replaceable arms. You crack an arm on the Smart35 you are going to have a very bad day. With the AOS 3.5 you just undo two frame screws and the motor screws and swap the broken arm. It takes less than 5 mins! As for motors I would recommend 1505s with analog/naked vista. 1404s are necessary to stay under 250g with stock vista. 1804 are too flat for my liking (pancake motors have too much inertia for their torque) and 1806 motors are way too big for 3.5". 1806 is my pick for 4" freestyle.
Ciao Chris bel video.. voglio costruirlo anch'io ma la Fc non si trova, per ora non è disponibile, hai un suggerimento per una valida sostituta? Grazie
Would it be possible to get a CLI dump for this quad? I'm going to build this with the exact same parts so would be nice to have your tune on it as well. Could you create a Google doc and upload the tune for all your builds? I am sure people would like to build them with your tune.
Looks great! You mention @7:00 that the larger torsional stiffness leads to resonant modes being pushed up higher in the frequency range. Do you have any literature recommendations to learn more about this idea from a technical physics perspective? Thanks! *UPDATE: NEVERMIND! I just remembered that resonant frequency = sqrt(k/m), 'k' being stiffness and 'm' being mass. So it would make sense that higher torsional stiffness increases resonant frequency! Just leaving this comment up for anyone else that might have the same question :)
Nice frame! Might consider this. Was waiting for you to make a sub 250g build actually, tbh :) I have one question. With 3800KV motors would 3.5x2x3 be ideal props?
Loving the content. With the build you say that if you want a beefier motor then go with the 1507 over the 1404s. What kv 1507s and why would you choose the 1507s rather than upping the kv on the 1404s to 4600kv over the 3800kv. Thanks mate
Worth watching my video on choosing motors if you haven't already as it answers your question. The KV would be the same on the 1507s. Larger motors provide more torque and that will give more responsiveness in the air. KV doesn't change the torque of the motor just its torque constant.
I'm about 90% finished with my build with this frame. I'm using an iFlight 20x20 Twin G F7 FC and 45 amp ESC stack in the rear with a Shark Byte TX5S.1 whoop VTX in the front. I managed to fit a 1000 uf capacitor between those and will be running a Crossfire Nano RX attached to a skeletonized plate above the VTX. The motors are Diatone Mamba 1505 3800 Kv. Packaging all of it has been a fun challenge and the frame has exactly enough room. I'm just waiting on a VTX antenna to arrive. I'm still not sure exactly how I'm going to mount the Crossfire antenna. Building smaller quads has me considering getting Tracer or Ghost, or even Express LRS, just for the smaller 2.4 GHz antennas.
That sounds like a great build. There have been some fantastic SB builds in the AOS 3.5 putting the stack in back and VTX up front so you are in good company! If you are considering a new link I cannot recommend anythign but ExpressLRS. Its cheaper and has better performance than the competition. And the EP2 receivers are perfect for tiny builds.
@@ChrisRosser I had a Brain 3D 20x20 mount for the Immortal T that I installed on the underside in the front. I was hesitant to do it at first, but it actually works out nicely. It keeps the antenna slightly pressed against the arms so it won't vibrate much at all, and it acts as front landing gear. I used 12x12 TPU landing feet in the rear from Brain 3D as well, so it's not scraping carbon on the ground when I land.
The orientation of the carbon fiber in the arms from CNCMadness is aligned to the diagonal struts instead of the horizontal struts, unlike you describe in the video. Is that intentional?
any thoughts of doing a light version for mid range with a hd camra? my mod-l with 3.5 is 36g frame and tends to have bit of jello at mid throttle;. with a hd cam it's 255g also, do top mount batteries stick in trees worse?
Light weight frames have more trouble with vibration as you have experienced. I might go for a sub250g frame for Naked Go Pro etc. but that will probably be 3" props. I run exclusively top mount and they don't stick in trees much. Not sure why it would make any difference.
Curious if you played around with where the vista sits? Seems like it hangs outside the centre of mass a ways but I’m thinking you’ve thought that through extensively so curious if you found any benefit in moving things more central?
The weight of the vista is somewhat offset by the camera up front. Mainly its about ease of build and maintenance. Once you start stacking the vista on top of the flight controller you can run into issues with vibration. If you mount it to the top plate it makes it more difficult to take the quad apart for maintenance. For even smaller quads it may be necessary but fortunately the AOS 3.5 has space.
@@ChrisRosser Thanks Chris, after building the GEPRC 3.5 last night there were definitely a couple times where I wished it wasn't stacked like you mentioned. I've got an order in with CNC Madness for one of yours, just waiting for shipment after their vacation! Cheers and thanks for all the work you are doing on these!
Hi Chris love the look of this as I can use a vista I already have, while I’ve built a few quads tuning is not my strong point. Do I need a specialised tune for this build or will it fly well on stock Betaflight?
Thanks for the content and the frame, Chris! I have been waiting for this frame for quite a while! One question though, can a full-size DJI air unit fit into this frame? I have a few of those lying around.
Looks like a great frame … I ordered one up. In the prehistoric drone past…. 2013 or so…. Frames were separated into a dirty and clean portion. The clean portion was a plate to mount the electronics on including a flight controller. The clean plate was mounted to float on dampeners to help isolate it from mechanical vibration. I wonder why this isn’t used any more. Now When the FCs are mounted vibration is transferred directly from the frame into the FC (through the screws) even though there are those small rubber grommets. Doesn’t make sense…. Maybe you have some insight? Why not just mount the FC to a plate floating on dampeners?
Dude!!! Thanks so much for the in depth study. I started a journey with the same objectives, but with less refinement and physics domain. And I'm also a noob in the FPV fly world. I'm planning my first machine and I think I just found the frame... Do you know if hybrid cameras, like the Runcam Hybrid, would have a nice fit and protection with these plates? I know that'll fit. But, because of the size I don't know if: - Would it have a nice range of angle adjustment? I imagine that maybe the angle adjustment would be limited in some way... - Would the plate protect effectively both lenses? I imagine that the upper and bigger lens would be somewhat exposed... Cheers! And keep rocking!
19mm/20mm Cameras with a single lens should fit. Double lens cameras like the Tarsier don't fit. You should have plenty of adjustment for a single lens camera.
Nice video and nice frame. 249gr, so as soon as you install the ELRS receiver, you are over the sub250g. At that point, you have to go down in battery capacity. Are there 750mAh 4S batteries? How much flight time are you losing? Just 3:15 of spirited flight with an 850mAh... Thanks!
You can go naked Vista to save a bunch of weight. Or juse use a lighter battery strap than my big rubber one. You can get 750mAh and 650mAh 4S packs. 3+mins of hard freestyle is pretty good. You'll get over 10 mins of cruising: ruclips.net/video/MKFJpcpyn78/видео.html
I have just purchased this frame with a 20x20 stack and will be using a vista (possibly naked). How do you feel about the fpvcycle 16mm motors? There is only one 3.5" prop size with a 5mm shaft mount which is 3.5" with a 2.0" pitch. Thoughts over using 1404?
I think I prefer the M2 system or a standard T-mount over the M3 with washer approach used on the FPV cycle motors. 16mm should be an OK size but I've found the 1504s from iF to be great motors. They put up exceptional numbers in the bench testing I did.
@@ChrisRosser I appreciate the reply. I ended up going with the Diatone Mamba 1404 and am really impressed. 2mm internal shaft, about 10g with short wires, unibell, magnets are really strong compared to the emax 1404 ecos I was using prior on my Babyhawk.
Thank you so much for your content, digging the scientific approach! I'm also really interested in this frame. Do you know if there is a shop in Germany that is interested in stocking your frames? As Steve West mentioned shipping costs are quite high unfortunately.
I'm not in contact with any but I'd really appreciate it if you'd ask your favorite shop to stock my frames! I'll work hard to get them as many as they want.
Awesome frame, I want to use it in a 3.5 inch build with 6S battery (around 650mah), I was thinking on 2004 size motors (Emax eco 2 or NBD Flow) but not sure which KV can work better for freestyle 2000 or 2400 or 3000 ? thanks.
I've been thinking of making this my main daily flyer. However as a SB user I am particularly interested in the new 30x30 1w vtx currently being tested for freestyle. I wonder if you could perhaps take this into consideration allowing the mounting of this new vtx in your frame. Front or rear and then a 20x20 and a 25x25 whoop mounting holes.
I just ordered one of these and I'm going to hopefully use the components from a 4" Shark Byte racing toothpick that has been plagued with jello. A JHEMCU GHF411 35 amp AIO (with blackbox), BetaFPV 1505 3600 Kv motors, Crossfire Nano RX, Shark Byte TX5S.1 VTX, Runcam Nano HD (I'll also be beta testing the new Runcam HDZero Micro), TrueRC Singularity. Hopefully this will give those components new life in something that won't exhibit any jello whatsoever.
I've heard concerns about compatibility of the H7 with some betaflight features like RPM filtering. I would stick with the F7 until H7 flight controllers are a little more common.
Thank you Chris for such a interesting things. But have you done any analysis on sandwich cinewhoop frames like bumblebee or greenhornet from iflight? I was really surprised to see in debug gyro only one peak of resonance at frequency almost at 300hz. It seems to me that's a great directoin to develop frames more close to this design to prevent vibrations
Are the Xing2 1404 really too weak for this build? Are they only chosen to stay under 250g? Are the Diatone 1505 better suited? Would be 10-12g heavier right? Would it be much louder? Less smooth? I'm looking for a stealthy DJI quad for in the park that flies silent, smooth but also enough punch for some fun.
The 1404s are great for this build. If you are running analog or naked vista then 1505s will give a little more performance and still stay under 250g. It won't be any louder or less smooth in my opinion.
@@ChrisRosser thanks! I'm not concerned about sub250, if it's 260 or 270g I don't care, just looking for a nice and quiet DJI quad for in the park but still with good performance when needed.. many people keep saying here the 1505 are better? I already have a 5" 290g with 2004s though for larger areas, just looking for some close range fun. Loudness is a concern though, I can't fly my 5" 290g quad here in the park.
I want to get into FPV drones and I was going through your videos and I had a question you don’t seem to answer. Why does everyone unes LiPo and not lithium like 18650s?
18650s cannot supply the current required for freestyle. Quads can draw 100+ amps and 18650s cannot supply that much. Lipos are manufactured using a different process that gives much higher max discharge rates.
Hello Chris, may I know the ideal weight for an analog AOS 3.5 built using an 850mAh battery? I am going to transfer the electronics from my current 3inch to the AOS 3.5 frame. I did a quick calculation on the AUW of AOS 3.5 using existing 4in1 ESC + F7 FC + VTX + Ratel2 Cam + BH1504.5 motors + 850mAh CNHL Battery = 246g. If I go with iFlight Xing2 motors then the AOS 3.5 AUW goes down to 246-12 = 234g.
@@ChrisRosser Thank you for the ideal weight. I am still trying to find more people to do a group buy as the costs to ship to Singapore are expensive, USD19, more than 1/3 of the price of the AOS 3.5 frame. I believe there are no hobby shops over here that stock this frame.
hi chris, thank you so much for the video (and your whole channel), and for coming up with this frame. I'm buying it next week, but going with shark byte (TX5R.1), and I was thinking of going with XING 1504 3900KV motors instead, for a bit of extra power (and the iFlight Beast H7 55A AIO). do you think it's worth it, or should I stick to the 1404? btw, I looked at the size you mentioned (1506) but I can't find anything other than 3000KV or 4300KV (which seems excessive, but what do I know? 😃). are there any around the 3800-3900KV mark? which one would you suggest? THANKS!!
Hi. I'm afraid the 5R.1 doesn't fit in this frame, it is just too long. The whoop board fits perfectly though with a 20*20 ESC and FC in the rear. 1505 is a good size to stay under 250g. 3800kv is right for 4s.
@@ChrisRosser ok, 5S.1 it is, then 😃 are the diatone mamba 1505 good, or do you have a better one in mind? mind you, the XING 1504 would still keep below 250g. oh, btw, I just bought the frame, ahead of schedule 😀
Love your content Chris. I really like to understand why things behave the way they do. Looking to build one of these as I love the smaller form factor quads. Any idea if there will be any UK stockist as shipping costs from cncdrones jacks the price up quite a bit ?
Hi Chris I have just bought your frame to review on my channel. It’s cost me $100 Aussie Dollars to do so. For my review I’ll be using your recommended setup. Can you please post the PID & Filter settings below as a diff?
Hello Chris. Quick question: if I put the things of a Protek35 on this frame, would it perform? (BeastAiOF745a, Xing 2203.5 3600kv, Vista, 4S) It’s for freestyle purposes🤣
I have a query hopefully someone could help with please. Does anyone know what size screws are needed to build this frame? I purchased it a while back from cncmadness / cncdrones and I've just tried to put it together but it seems like they accidently included the wrong screws because they are too short. I only have 2 countersunk screws that are of a suitable length for the arms and the base plate. I'm based in the UK so I was hoping I could just buy some appropriately sized screws from somewhere.
I'm looking to get this frame the only concern being the offset of the flight controller since it's not in the center of the frame does that effect the flight characteristics?
I have since built and flown my AOS frame. With only RPM filtering the backbox gyro filtered chart is perfectly flat above 60hz. It really is an incredibly quiet frame. I don't think there will be any issues obtaining a very impressive tune. Well done!
A _great_ price for this design, too. Will you be offering this with your new arm CF? Ain't this a great hobby? Not only do we have to worry about burning our houses down, we gotta worry about components de-soldering themselves. . .
@@ChrisRosser I've been looking at the 3.5" to move up to, and when I do, it's going to be this frame, for sure. It'll likely be the cheapest build in terms of components, but I'll have a beast of a foundation.
Hey Chris, I've noticed my frame: ruclips.net/video/bSpD7fuXXVI/видео.html and the others I've seen on RUclips, have the arms cut with the carbon opposite to your design. Was this a design change or were they cut improperly? I don't think it will be a problem for me, but it was pointed out to me and now I'm curious. Absolutely excellent frame!
If it's at 90degrees don't worry. The performance at 0 and 90 is the same for standard layup. The arms will be cut in different directions to best use the sheet and minimise waste.
15:20 - AMEN BROTHER, AMEN!
Glad you feel the same way Mark! Blackbox for the win.
Thanks for producing content Chris. I love learning whatever you're teaching.
My pleasure! This has a little bit of education but I'm cooking up a video on ESC tuning and carbon fibre that I think you'll like.
Hi Chris, I'm a big fan of the work your doing and recently purchased this frame from a UK vendor (not going to name them publicly). I have been very disappointed by the quality of the frame with one of the camera plates missing, undersized holes in the bottom "X" plate, the "X" plate and arm braces have also been countersunk but supplied with domed bolts (i.e. weaker than need to be). In addition to bolts missing from the pack there were an additional 18 "cheese head" bolts and an additional aluminium spacer supplied. There were no instructions, parts list or branding on the frame, other than a made in Canada label. I live near Royston and am happy to show you the frame if you want to inspect it or can supply photos. The vendor is reputable and I've used them regularly with no quality issues.
This looks awesome. The only problem I have is that my old school 3" with 1407 3600kv is still so incredibly much fun. What it lacks in smoothness it makes up in speed, perfect for flying like a madman after a stressful day.
Sounds like a blast! Glad to hear you have a rig you love to fly.
@@ChrisRosser i have question. By your graph, transtec beetle 2.5 inch quad at 250gm should perform at red/orange line. But how is that in Joshua Bardwell's video on that quad, when Vanover flies it, it almost /fully performs like a 5 inch freestyle or blue line? Which to achieve at 250gm should have used 3.25 inch props?
@@AfafPrinceOSH I mean it just doesn't perform like a 5". Not even close. Vanover is a great pilot and he flies it well to be sure, but have you seen what he can do with a 5" quad?
I have a GepRC Rocket Lite with 2.3" props which is pretty similar disc loading and you can freestyle it but you would never think that it flies like a 5". It has much less power, speed and acceleration and much worse propwash handling. A great pilot can fly around those limitations and that is what Vanover is doing.
@@ChrisRosser oow okay, now I get it
@@AfafPrinceOSH Vanover does a great job at making quads look good! No worries 😁
Great looking build Chris... you're knocking it out of the park at the moment..Good luck & keep up all you're good work.
Thanks for your support 👍
The babyhawk 2 has a very tough frame. I have yet to break any part of the frame. But your frame dose do a 1up on the motor guards on the arms. Babyhawk dosnt have this and that’s the weak point on it. Motor bells/shafts bend very easily. So I’m sold. Orders in for a 3.5 and 5.5. Thanks for all the hard work on your frames.
Hello Chris
I thought the 4mm arms on the AOS 3.5 are tough but it broke after a crash onto the grass from 30+ feet.
I suggest everyone get a replacement arm when they order an AOS 3.5 frame.
It is a pain to buy a $6 replacement arm when the shipping costs = $19.
I build two AOS 3.5 with identical electronics and the only difference is the motor - one with Xing2 1404 (240AUW) and the other BrotherHobby 1504.5 (248AUW).
I can tell you that the frame with BrotherHobby motors is way more fun to fly than the Xing2. The Xing2 just lacks power and this lack of power is especially true when coming out of dives.
Hi David, sorry to hear you had a crash and broke an arm. If you could reach out to me on email and send an image of the damage that would be very helpful. AOS 3.5 is coming to Banggood soon to help with shipping costs for international pilots.
I can't believe you did this man.....I love love love my babyhawk 2 hd , and if this is better.... Oh man...
Amazing video! Nothing left behind! I love how you explain everything clearly 👍
Awesome, thank you!
Hi Chriss, I was thinking of pulling the trigger on a Babyhawk. But building myself just seems like more overall enjoyment. Just double checking if a few changes to parts make sense (based on what I can get). I'm happy to take a few extra grams.
- Vista + polar
- Betafpv 1505 3600kv
- Diatone Mamba F722 Mini
- Crossfire Nanno
Yes those look like great choices. For sub 250g you may need to go with a naked Vista.
@@ChrisRosser thanks a bunch mate. Btw, I just finished tuning a th2 freestyle with your methods. Never flew so good!
Next up the "work" betafpv 85x cine whoop.
Hey Still It, get the AOS 3.5, you won't regret it. My build is about 250g with an AIO board, 1404 motors and Vista/Nebula pro on light 850mah lipos. You can stay well below 250g with 650mah batteries. Here's how mine flies: ruclips.net/video/EQNW_taSa7Q/видео.html
Love this video! So much thought has gone into the design
Would be cool to show off your quads on a plain workbench so we can better see the beauty 😍😍 thanks for what you're bringing to the hobby!
Thanks for the idea! I'll try that next time.
Thank u again for all the inf. u have giving us i feel that some of that inf we can use in other frames as well and that the beauty on sharing the knowledge.
You are welcome, I hope it helps you with your future builds. 😁
Ordered this an hour before you posted this video 😁 I can't wait to build and fly this!
Fantastic. Thanks for your support. I hope you have a lot of fun ripping the little guy around! I've been surprised by how much fun it is to fly. I always take it out with me even when going to fly my 5inch quads.
@@ChrisRosser I have been searching specifically for this size and weight class, since I'm so in love with my TP3, but sometimes want a bit more weight and punch. BTW, what are your thoughts on motor sizes and kv for 4S? I'm considering 1506/1606/2004 since they have similar stator volume 🤷🏻♂️ Also, could I fit 1300 mAh 4S packs on here?
@@MartialArtsDKdotcom I would probably go for a 1505 with an 850mAh 4S. Otherwise you'll find that you move away from the optimum weight to prop size ratio.
@@ChrisRosser I see 👍🏻This goes for analogue right? Thank you for taking the time to reply 😊
I think this would be a nice winter time build. Beautiful design.
Well that's confirmed why I like the Diatone GT349 so much. Frame ordered.
@@ChrisRosser Yep, maybe with a naked GoPro for better HD. And the AOS-5 is built, fine tuned and fantastic. Full build and tune video is on the way. The frame design, particularly the arm design makes tuning so much easier. 7 inch in the planning?
Yes hoping to get prototypes cut this week. Nick is super busy but I'm chasing him!
Mine just arrived in the mail today! I'm really excited to build it, just waiting for my motors and props to arrive.
This Frame design reminds me a lot of the Emax babyhawk HD. Great review and information.
Thanks for watching!
I LOVE my AOS 5 and my 3.5 was just shipped yesterday, I'm very excited.
I hope you enjoy it. My AOS 3.5 really surprised me. I originally thought: "Yeah this'll be OK for sub250g but I'd always prefer a 5inch". But the first time I flew it I really fell in love with the little guy and I fly it all the time now!
This is art. Well done Chris!
Thank you for your kind comment!
This looks like a great build mate 👍😎 Perfect for running without a HD cam IMO, quite often I use the dji goggle DVR to upload, looks pretty good.
BTW I’ve been using those little sigma antennas for quite a while and really like them, so light and seem to work just as well as the caddx antenna and they are surprisingly durable given how flimsy they feel in the hand.
Thanks 👍 I'm glad you like the build!
Just got my 5.5 last night,
Put it together and it's lovely.
saw the 3.5 on the site last night while building and instantly added to cart.
just need some motors...
interesting sir, you are the only person that goes so deep into the topic
Thank you! I think the detail behind the frame design makes it much more interesting.
I own the frame as well and I'm quite pleased withe the quality and rigidity, unfortunately the runcam hybrid camera will not proper fit, which was actually my plan to fit in all along.
i just got this frame now. seems the camera plate design has change with regards to the mounting holes for screws. theres quite a lot of mounting possibilities with the new camera plate . I am also planning to go for the runcam hybrid, and your experience starts to doubt me too. funny thing is my fc is whoop type.
i recently got a crux35, im already on my second bottom plate lol, i do like the idea of replaceble arms, but i come in at around 190 grams with that same 850mah battery but the stock xt30 version with smaller cables, added vfly self powered beeper with gps passthrough (because thats the only one i could get from where i was making a larger order) and the stock motors although i just ordered these exact motors for my super crux35 build im making where i am going to stick 2 bottom plates together so its 6mm thick, because the bottom plate is only 13.5 grams so i think its a good trade off for durability, and i can put on a smo4k on it, upgraded vtx and aio fc, and still be under 250 grams. the resonance thing would be interesting to me with the crux frame, it flies just so dam good i cant imagine being single bottom plate could be very detromental on such small arms, espesually when i do my super crux 6mm thick boii
From the pov of academic discussion; I think it gets a little bit tricky looking too hard at the disc area graph at the lighter end of the spectrum. There are other factors which suddenly increase/decrease in importance relative to bigger quads. Prop blade volume/inertia, relative weight of electronics to motor size and frame weight etc. All the compromises become more important. It's not a bad place to start but optimising micro setups is tricky and requires quite a bit of trial and error.
I've found that prop tip speed and disc loading is the correct first order analysis approach even for quite small drones. There are of course second order effects to take into account such as prop pitch and blade count and motor sizing. These follow on naturally from a consideration of flying style and necessary motor torque for the chosen prop. I'm hoping that applying these rules in sequence can reduce trial and error! The most difficult thing is calculating what a particular build will weigh before you build it 🤣
@@ChrisRosser the factors I'm talking about here relate to the compromises that put a quad on one of those lines.
For example motor torque. You may be able to say ok from 5"->4" the disc area is 16/25 so the motor should be 16/25 of the size.
At smaller scales when you do this you add more weight than you should because the electronics which were negligible take a larger percentage of the mass. So if you want to stay on that same line you might need 12th/25 of the motor volume to hit the target weight. Same with frame strength.
Effectively you have these "steps" which relate to the weight of electronics amongst other things. A whoop needs 8-10g of electronics, go up to a 3s 3" and it's 15-20g, go down to 2.5" and it's STILL 15-20g because you need the same electronics.
@@frasersteen Absolutely right. 100%. For small quads you cannot hit the same disc loadings as you can for 5". That doesn't mean the lines are wrong just that we have to settle for what we can achieve. The disc loading lines still allow you to compare your build with quads of different sizes to determine roughly how it will feel to fly *assuming that the max prop tip speeds of the rigs are comparable* which can be tricky to achieve for small quads as well.
hi chris, I've finally received the frame from CNC Drones, and there's something I'm not sure you're aware of. I bought the countersunk version, and while the long hex-head screws which mount in the bottom use the standard 1.5mm hex key (which is part of EVERY FPV toolkit on the market), the short screws used on the top plate in the same standoffs use the 1.3mm hex key. maybe it's asking too much, but I think those should be changed, so you can use (and carry around ) the same hex key driver to work on both.
also, if I may suggest an improvement, you could add a cut-out on the lower X piece which retains the arms, so you can access the rear-most screw for a flight controller like the iFlight Beast .thanks!
you can always change the screws easily?
So you did choose the Avan Scimitar props ! I was really hesitating between those and the HQProps and the Gemfans ones.
Funny enough I just upgraded my babyhawk II HD with an iflight F7 beast and was looking for a 3.5 inch frame to replace the not great emax frame and this pops in my feed!
Looks like my AOS5 is getting a baby brother :)
@@ChrisRosser I'm sure it will be great if it handles anything like its' older brother :D
Completely agree with your sentiment on sub 250. I always thought that when I went to 5inch that I'd never look back, but with 3.5 at just under 250 you get something that you can toss and carries its momentum well but also turns on a dime if you want it to, it's great!
Hi Chris, have you tried the Babyhawk II? Will you do a frame analysis of it in the future? Thanks for your videos!
Poking antenna out of the front top plate, feels more optimized for return, which is what you want. It can give in a crash but is fairly fixed in place. The signal is absolutely horrible with the antenna mounted on the arms. Running 6s skystars AM42 stack. HDZero freestyle VTX fits in front if you remove the standoffs and replace arms screws with 2mm nut and screw.
Please consider applying your superpowers to to a pure racing frame ;)
Oh man, you are going to be psyched for the AOS 5R. I'm taking it to the next level with a custom carbon fibre material.
@@ChrisRosser ooooh!
indipendente arms great, although on these small and light quads, it's probably easier to just beef up the frame a bit and make it nearly unbreakable, weight you save by not using extra screws can be used somewhere else on the arms... i flew micros for few years and haven't broken single arm...
A few people have reported cracking their bottom plates on their micros and being very frustrated (having to rebuild the whole quad) so it is a problem for some people. Replaceable arms also improve vibration and resonance performance over unibody frames.
I've two quads with this great frame! But I wish it was possible to buy more spare parts. Not only an arm but the camera mount also. I've one very damaged camera mount that I soon need to replace.
Hi Chris, did you get the ELRS ceramic receiver installed? I'm curious how it does being placed between the vista and FC. Great content as always and I appreciate your time, hard work, and dedication you have for the hobby...
I like this. Planning on doing a build soon. Wow that was fast, every part is on back order...
Fantastic. I hope you love your AOS 3.5!
@@ChrisRosser Apparently, it's gonna be a minute...LoL
On the topic of the AIO's with Blackbox, I can recommend a fairly cheap and quite good option - JHEMCU GHF405AIO Pro - only the Pro version though, I have a couple of 45A ones and they are great, especially for the price. Not that great at overclocking though probably due to BGA bare die, do not even try 240mhz on this one, you'll reboot in the sky :) 192mhz definitely works, 216mhz YMMV :)
Thanks for the info!
Id love to hear your thoughts on the RR outlaw and Umagawd 2fiddy, since we're talking sub250
I'd like to hear too! Actually, Chris explains drawbacks of props bigger than 3.5 in the sub250 category in his video "Choosing the right prop diameter...". However I fly 2fiddy with 2005s at 248g AUW with bi-blade props and 720mah 4S. I have no complains so far :) it's great! Maybe after all it's just a question of feeling/personal preference. I admit staying under 250 is a bit tricky in 5", for example my vista is de-cased.
I might try a 3.5 to see the difference.
@@stormriderfpv great! Do you get exceptional flight time due to its lightness?
@@ChrisParayno Freestyle: 8 to 5 min, it variates a lot depending of throttle usage. I haven't tried a simple cruise.
Great video. You should produce a 3" race frame, keep it as light as possible and with enough space to fit a a 20 * 20 AIO board.
Thank you for your support and the great suggestion. I'll certainly look into a 3" racer!
ive just finished this build but with slightly different electronics but with chris recommendations, i advice all you just use the iflight beast if your going for the aio whoop as my cheaper jhemcu whoop board have problems with blocked usb ports with the standoff, as the usb port is located 2mm to the left side (unlike iflight) i end up removing this standoff for the time being while i tune it.
You gotta 4.3 tune for this guy?! I bet it'd work pretty well on my babyhawk II HD.. I need to tune it 😂
hi Chris. will you release a v2 of this 3.5"?
The only part that gets me about that frame is the lack of the antenna mount.
Especially since that can be a big source of vibration.
Definitely needs a properly mounted vtx antenna for best signal and least amount of vibration.
Same thing with kabab’s tooth fairy frame!🤔
Vtx mounts are tricky. I cable tie my antenna to the arm and that works great with DJI. If you're on analogue then it's more of a tradeoff. A stiff mount will add significant weight and a flexible mount is bad news for vibration.
This is awesome. I swear I was just thinking the other day that I wish you could shrink your 5" design down to 3.5" lol. I've been wanting to try a 3.5" quad since the Babyhawk 2 came out but that one had a few things I didn't like. This design ticks all of the boxes for me. I'm gonna go with a naked vista/nebula pro and BetaFPV 1505 3600kv motors. Can't wait!
Oh that sounds like a perfect build. What Flight controller are you going to put in the frame, are you going for sub 250g?
@@ChrisRosser I think I'm going to use a JHEMCU 35A AIO 20x20 that I have laying around. It's an F405 with 4 UARTs and black box, plus a 9v 2A power supply for the vista. Pretty sure the naked vista will stack on top of that without having to even use the second bay in the frame. I don't care that much about the 250g weight but it should be pretty close to that I think.
@@flipfpv I wouldn't stack the vista on top of the FC if you have space in the rear for it. That can cause gyro noise.
@@ChrisRosser Oh, good to know. I'll put it in the back then. Thanks for the tip! BTW, CNC Madness is on Holiday until 8/9 so no shipping until then.
What do you think of vertical frames? As they have a very different geometry, I would be very interested on your thoughts on them
Very interested. Curious - Can the frame accomodate 4" props, albeit a tight fight? (Some 3.5 inch frames can.)
I don't think so. It's a pretty tight fit for 3.5s. All of my frames are pretty optimized for a particular setup so there ends up being less flexibility as a tradeoff.
Would have bought this as it looks like a great 3.5 I've been looking for but $22 for shipping to UK and possible import charges just too much.
Shame you don't sell through the main UK shops like unmannedtechshop or hobbyrc.
I do, stock will be getting over to the UK in the next few weeks. I expect UT and yourfpv.co.uk to be the first to get frames.
Hey Chris nice design, can you fit a full size DJI HD camera unit with the built in DVR in this frame or is it only able to take the vista. I like how your frame doesn't show props in view unlike the geprc smart 35 HD, but in all fairness the geprc smart 35 frame does comes with four independent front and back brace arms for reinforcement as well but you have to put those on your self. I do have a question regarding the back brace, aside from symmetry and looks what's purpose does it serve unless your flying backwards all the time, wouldn't it save some weight if you lose the back brace. Doesn't all that reinforcement obstruct the wind flow from the props and can possibly cause snagging in the trees. I mean you have the vista unit siting in back it's already tail heavy, one of the things I did like about the geprc smart 35 is it has all the component in the center so it's very well balanced. I do like the horn tips for protecting the motors I believe Tommy Tibajia was the originator who came up with that. From my research alot of pilots been saying that the 1404 motors being used for the 3.5" are under power and the ideal size motors for this size quad would be a 1804, 1806 with 4,000KV +/- but I guess that would probably be tricky to get it under 250g.
You can fit the DJI camera in it with the Vista. The Air unit doesn't fit I'm afraid. The braces are not only for strength they also improve the resonance performance of the frame. I think the main benefit of the AOS3.5 over the Smart35 is the replaceable arms. You crack an arm on the Smart35 you are going to have a very bad day. With the AOS 3.5 you just undo two frame screws and the motor screws and swap the broken arm. It takes less than 5 mins!
As for motors I would recommend 1505s with analog/naked vista. 1404s are necessary to stay under 250g with stock vista. 1804 are too flat for my liking (pancake motors have too much inertia for their torque) and 1806 motors are way too big for 3.5". 1806 is my pick for 4" freestyle.
Ciao Chris bel video.. voglio costruirlo anch'io ma la Fc non si trova, per ora non è disponibile, hai un suggerimento per una valida sostituta?
Grazie
Would it be possible to get a CLI dump for this quad? I'm going to build this with the exact same parts so would be nice to have your tune on it as well. Could you create a Google doc and upload the tune for all your builds? I am sure people would like to build them with your tune.
Yep drop me an email!
@@ChrisRosser Thanks Chris, I can't find your email anywhere though?
@@skinner9305 chrisrosser91 (at) gmail.com 👍
Looks great! You mention @7:00 that the larger torsional stiffness leads to resonant modes being pushed up higher in the frequency range. Do you have any literature recommendations to learn more about this idea from a technical physics perspective? Thanks!
*UPDATE: NEVERMIND! I just remembered that resonant frequency = sqrt(k/m), 'k' being stiffness and 'm' being mass. So it would make sense that higher torsional stiffness increases resonant frequency! Just leaving this comment up for anyone else that might have the same question :)
Nice frame! Might consider this. Was waiting for you to make a sub 250g build actually, tbh :) I have one question. With 3800KV motors would 3.5x2x3 be ideal props?
Yeah that sounds like a good combination.
@@ChrisRosser Thank you so much! Have a lovely day!
Loving the content. With the build you say that if you want a beefier motor then go with the 1507 over the 1404s. What kv 1507s and why would you choose the 1507s rather than upping the kv on the 1404s to 4600kv over the 3800kv. Thanks mate
Worth watching my video on choosing motors if you haven't already as it answers your question. The KV would be the same on the 1507s. Larger motors provide more torque and that will give more responsiveness in the air. KV doesn't change the torque of the motor just its torque constant.
@@ChrisRosser thank you very much. Me and 2 other lads are all building 3.5 off your recommendations. Thanks for the info 👌
It would be nice if you shared the FC (AIO), motors, and props you used in the description. BTW Love your videos!
DOH! thanks
@@ChrisRosser Had to click "show more".
@@ChrisRosser Thanks, I love your approach, as I too am an Engineer by profession. Absolutely considering an AOS frame for a new build.
I'm about 90% finished with my build with this frame. I'm using an iFlight 20x20 Twin G F7 FC and 45 amp ESC stack in the rear with a Shark Byte TX5S.1 whoop VTX in the front. I managed to fit a 1000 uf capacitor between those and will be running a Crossfire Nano RX attached to a skeletonized plate above the VTX. The motors are Diatone Mamba 1505 3800 Kv. Packaging all of it has been a fun challenge and the frame has exactly enough room. I'm just waiting on a VTX antenna to arrive. I'm still not sure exactly how I'm going to mount the Crossfire antenna. Building smaller quads has me considering getting Tracer or Ghost, or even Express LRS, just for the smaller 2.4 GHz antennas.
That sounds like a great build. There have been some fantastic SB builds in the AOS 3.5 putting the stack in back and VTX up front so you are in good company! If you are considering a new link I cannot recommend anythign but ExpressLRS. Its cheaper and has better performance than the competition. And the EP2 receivers are perfect for tiny builds.
@@ChrisRosser I had a Brain 3D 20x20 mount for the Immortal T that I installed on the underside in the front. I was hesitant to do it at first, but it actually works out nicely. It keeps the antenna slightly pressed against the arms so it won't vibrate much at all, and it acts as front landing gear. I used 12x12 TPU landing feet in the rear from Brain 3D as well, so it's not scraping carbon on the ground when I land.
Hi ! Thanks, one question have I , is it possible to put a full air unit on it instead of the vista ? I ll looking for your reply, thanks again !
Unfortunately not, but a decased air unit may fit at 45 degrees.
The orientation of the carbon fiber in the arms from CNCMadness is aligned to the diagonal struts instead of the horizontal struts, unlike you describe in the video. Is that intentional?
No, that sounds like a cnc error. Reach out to Nick and he'll sort you out.
any thoughts of doing a light version for mid range with a hd camra? my mod-l with 3.5 is 36g frame and tends to have bit of jello at mid throttle;. with a hd cam it's 255g
also, do top mount batteries stick in trees worse?
Light weight frames have more trouble with vibration as you have experienced. I might go for a sub250g frame for Naked Go Pro etc. but that will probably be 3" props.
I run exclusively top mount and they don't stick in trees much. Not sure why it would make any difference.
Curious if you played around with where the vista sits? Seems like it hangs outside the centre of mass a ways but I’m thinking you’ve thought that through extensively so curious if you found any benefit in moving things more central?
The weight of the vista is somewhat offset by the camera up front. Mainly its about ease of build and maintenance. Once you start stacking the vista on top of the flight controller you can run into issues with vibration. If you mount it to the top plate it makes it more difficult to take the quad apart for maintenance. For even smaller quads it may be necessary but fortunately the AOS 3.5 has space.
@@ChrisRosser Thanks Chris, after building the GEPRC 3.5 last night there were definitely a couple times where I wished it wasn't stacked like you mentioned. I've got an order in with CNC Madness for one of yours, just waiting for shipment after their vacation! Cheers and thanks for all the work you are doing on these!
can I just switch the guts from my baby hawk into this frame? Would I need to mess with the tuning or anything?
Hi Chris love the look of this as I can use a vista I already have, while I’ve built a few quads tuning is not my strong point. Do I need a specialised tune for this build or will it fly well on stock Betaflight?
It should fly great on stock BF and is a great platform to learn how to tune. My filter and tuning videos will get you to a great tune in no time!
@@ChrisRosser thanks, I’m ordering now, any idea how long it takes to get to Australia roughly?
I personally use 650mah 4S on my 4" sub250. I get almost zero voltage sag with hard flying, and get 7 minutes of flight time!
Thanks for the content and the frame, Chris! I have been waiting for this frame for quite a while! One question though, can a full-size DJI air unit fit into this frame? I have a few of those lying around.
No I don't think so. Sorry! you could try a naked DJI air unit at 45degrees but that's a fair amount of work.
Looks like a great frame … I ordered one up.
In the prehistoric drone past…. 2013 or so…. Frames were separated into a dirty and clean portion. The clean portion was a plate to mount the electronics on including a flight controller. The clean plate was mounted to float on dampeners to help isolate it from mechanical vibration. I wonder why this isn’t used any more. Now When the FCs are mounted vibration is transferred directly from the frame into the FC (through the screws) even though there are those small rubber grommets. Doesn’t make sense…. Maybe you have some insight? Why not just mount the FC to a plate floating on dampeners?
Nice frame. Are there 3D printed antenna mounts for it? I don't like the tape-it-to-the-arm style of mounting.
Yep, there are some on thingiverse :D
Dude!!!
Thanks so much for the in depth study. I started a journey with the same objectives, but with less refinement and physics domain.
And I'm also a noob in the FPV fly world. I'm planning my first machine and I think I just found the frame...
Do you know if hybrid cameras, like the Runcam Hybrid, would have a nice fit and protection with these plates?
I know that'll fit. But, because of the size I don't know if:
- Would it have a nice range of angle adjustment? I imagine that maybe the angle adjustment would be limited in some way...
- Would the plate protect effectively both lenses? I imagine that the upper and bigger lens would be somewhat exposed...
Cheers! And keep rocking!
19mm/20mm Cameras with a single lens should fit. Double lens cameras like the Tarsier don't fit. You should have plenty of adjustment for a single lens camera.
Nice video and nice frame.
249gr, so as soon as you install the ELRS receiver, you are over the sub250g. At that point, you have to go down in battery capacity.
Are there 750mAh 4S batteries? How much flight time are you losing? Just 3:15 of spirited flight with an 850mAh...
Thanks!
You can go naked Vista to save a bunch of weight. Or juse use a lighter battery strap than my big rubber one. You can get 750mAh and 650mAh 4S packs. 3+mins of hard freestyle is pretty good. You'll get over 10 mins of cruising: ruclips.net/video/MKFJpcpyn78/видео.html
@@ChrisRosser Thanks for the answer!
I'll build one as soon as I can get my hand on a Nebula Pro + Vista combo. It'd be nicer to have them in EU...
I have just purchased this frame with a 20x20 stack and will be using a vista (possibly naked). How do you feel about the fpvcycle 16mm motors? There is only one 3.5" prop size with a 5mm shaft mount which is 3.5" with a 2.0" pitch. Thoughts over using 1404?
I think I prefer the M2 system or a standard T-mount over the M3 with washer approach used on the FPV cycle motors. 16mm should be an OK size but I've found the 1504s from iF to be great motors. They put up exceptional numbers in the bench testing I did.
@@ChrisRosser I appreciate the reply. I ended up going with the Diatone Mamba 1404 and am really impressed. 2mm internal shaft, about 10g with short wires, unibell, magnets are really strong compared to the emax 1404 ecos I was using prior on my Babyhawk.
Thank you so much for your content, digging the scientific approach! I'm also really interested in this frame.
Do you know if there is a shop in Germany that is interested in stocking your frames? As Steve West mentioned shipping costs are quite high unfortunately.
I'm not in contact with any but I'd really appreciate it if you'd ask your favorite shop to stock my frames! I'll work hard to get them as many as they want.
Ok, thank you very much. Wrote the mail to the shop! :)
@@skillless4927 which shop did you ask?
@@achimberend9310 I did ask n-Factory, but will ask other shops if they decline. Which shop did you have in mind?
Awesome frame, I want to use it in a 3.5 inch build with 6S battery (around 650mah), I was thinking on 2004 size motors (Emax eco 2 or NBD Flow) but not sure which KV can work better for freestyle 2000 or 2400 or 3000 ? thanks.
I've been thinking of making this my main daily flyer.
However as a SB user I am particularly interested in the new 30x30 1w vtx currently being tested for freestyle.
I wonder if you could perhaps take this into consideration allowing the mounting of this new vtx in your frame.
Front or rear and then a 20x20 and a 25x25 whoop mounting holes.
When the new VTX is available I'll certainly consider whether I can adjust the design.
@@ChrisRosser Great, I'll hold of a while then to buy one. 😃
I just ordered one of these and I'm going to hopefully use the components from a 4" Shark Byte racing toothpick that has been plagued with jello. A JHEMCU GHF411 35 amp AIO (with blackbox), BetaFPV 1505 3600 Kv motors, Crossfire Nano RX, Shark Byte TX5S.1 VTX, Runcam Nano HD (I'll also be beta testing the new Runcam HDZero Micro), TrueRC Singularity. Hopefully this will give those components new life in something that won't exhibit any jello whatsoever.
I hope so. If you still have issues with Jello you can always reach out to me.
3" frame for 18650 nanolongrange cruiser?
U think u can share your betaflight configuration? I have the exact hardware and battery 😬
Any opinions on Mamba 1505 3900 kV vs Xing2 1404 3800kv for this frame?
That's awesome! one question though, is there any benefit/downside of using an iFlight Beast H7 instead of F7? Other than the slight added expense...
I've heard concerns about compatibility of the H7 with some betaflight features like RPM filtering. I would stick with the F7 until H7 flight controllers are a little more common.
Thank you Chris for such a interesting things. But have you done any analysis on sandwich cinewhoop frames like bumblebee or greenhornet from iflight? I was really surprised to see in debug gyro only one peak of resonance at frequency almost at 300hz. It seems to me that's a great directoin to develop frames more close to this design to prevent vibrations
I'm working on a detailed review of the Betafpv Pavo30.
Are the Xing2 1404 really too weak for this build? Are they only chosen to stay under 250g? Are the Diatone 1505 better suited? Would be 10-12g heavier right? Would it be much louder? Less smooth? I'm looking for a stealthy DJI quad for in the park that flies silent, smooth but also enough punch for some fun.
The 1404s are great for this build. If you are running analog or naked vista then 1505s will give a little more performance and still stay under 250g. It won't be any louder or less smooth in my opinion.
@@ChrisRosser thanks! I'm not concerned about sub250, if it's 260 or 270g I don't care, just looking for a nice and quiet DJI quad for in the park but still with good performance when needed.. many people keep saying here the 1505 are better? I already have a 5" 290g with 2004s though for larger areas, just looking for some close range fun. Loudness is a concern though, I can't fly my 5" 290g quad here in the park.
I want to get into FPV drones and I was going through your videos and I had a question you don’t seem to answer. Why does everyone unes LiPo and not lithium like 18650s?
18650s cannot supply the current required for freestyle. Quads can draw 100+ amps and 18650s cannot supply that much. Lipos are manufactured using a different process that gives much higher max discharge rates.
How mutch weight would you save with analog ?
Would a runcam hybrid 2 fit? It's a nice cam for analogue lightweight freestyle :)
What 1506 Motor do you recommend?
Hello Chris, may I know the ideal weight for an analog AOS 3.5 built using an 850mAh battery?
I am going to transfer the electronics from my current 3inch to the AOS 3.5 frame.
I did a quick calculation on the AUW of AOS 3.5 using existing 4in1 ESC + F7 FC + VTX + Ratel2 Cam + BH1504.5 motors + 850mAh CNHL Battery = 246g.
If I go with iFlight Xing2 motors then the AOS 3.5 AUW goes down to 246-12 = 234g.
The ideal is as close to 250g as possible for the build. The 1504.5 motors look good.
@@ChrisRosser Thank you for the ideal weight. I am still trying to find more people to do a group buy as the costs to ship to Singapore are expensive, USD19, more than 1/3 of the price of the AOS 3.5 frame. I believe there are no hobby shops over here that stock this frame.
hi chris, thank you so much for the video (and your whole channel), and for coming up with this frame. I'm buying it next week, but going with shark byte (TX5R.1), and I was thinking of going with XING 1504 3900KV motors instead, for a bit of extra power (and the iFlight Beast H7 55A AIO). do you think it's worth it, or should I stick to the 1404? btw, I looked at the size you mentioned (1506) but I can't find anything other than 3000KV or 4300KV (which seems excessive, but what do I know? 😃). are there any around the 3800-3900KV mark? which one would you suggest? THANKS!!
Hi. I'm afraid the 5R.1 doesn't fit in this frame, it is just too long. The whoop board fits perfectly though with a 20*20 ESC and FC in the rear. 1505 is a good size to stay under 250g. 3800kv is right for 4s.
@@ChrisRosser ok, 5S.1 it is, then 😃 are the diatone mamba 1505 good, or do you have a better one in mind? mind you, the XING 1504 would still keep below 250g. oh, btw, I just bought the frame, ahead of schedule 😀
@@pgabrieli Yeah the Diatone 1505s should be great! Thank you for your support in buying the frame. 😁😁😁
@@ChrisRosser thanks
Would this frame support everything that comes on the Smart35 Analog? Could I just drop everything from my Smart35 into this frame without issue?
Yes should work no problem with the AOS 3.5 O3!
Love your content Chris. I really like to understand why things behave the way they do. Looking to build one of these as I love the smaller form factor quads. Any idea if there will be any UK stockist as shipping costs from cncdrones jacks the price up quite a bit ?
Yes, there will be stock in the UK in the next few weeks. I have a couple of shops interested. Just need to connect with Nick about manufacturing.
Is there 3D print mount for naked gopro or smo 4k
Hi Chris
I have just bought your frame to review on my channel. It’s cost me $100 Aussie Dollars to do so.
For my review I’ll be using your recommended setup.
Can you please post the PID & Filter settings below as a diff?
Sure can! Here you go.
# diff -all
# version
# Betaflight / STM32F745 (S745) 4.2.4 Oct 20 2020 / 08:19:44 (fbcaf8c50) MSP API: 1.43
# config: manufacturer_id: IFRC, board_name: IFLIGHT_F745_AIO, version: f992353a, date: 2020-09-13T10:48:03Z
# start the command batch
batch start
board_name IFLIGHT_F745_AIO
manufacturer_id IFRC
# name: AOS 3.5
# feature
feature -AIRMODE
feature -DYNAMIC_FILTER
feature TELEMETRY
feature ESC_SENSOR
# beacon
beacon RX_LOST
beacon RX_SET
# serial
serial 0 1 115200 57600 0 115200
serial 1 64 115200 57600 0 115200
serial 2 0 115200 57600 0 115200
serial 5 1024 115200 57600 0 115200
serial 6 2 115200 57600 0 115200
# aux
aux 0 0 1 1800 2100 0 0
aux 1 13 3 1800 2100 0 0
aux 2 35 2 1800 2100 0 0
aux 3 36 0 1800 2100 0 0
# vtxtable
vtxtable bands 6
vtxtable channels 8
vtxtable band 1 BOSCAM_A A CUSTOM 5865 5845 5825 5805 5785 5765 5745 5725
vtxtable band 2 BOSCAM_B B CUSTOM 5733 5752 5771 5790 5809 5828 5847 5866
vtxtable band 3 BOSCAM_E E CUSTOM 5705 5685 5665 5645 5885 5905 5925 5945
vtxtable band 4 FATSHARK F CUSTOM 5740 5760 5780 5800 5820 5840 5860 5880
vtxtable band 5 RACEBAND R CUSTOM 5658 5695 5732 5769 5806 5843 5880 5917
vtxtable band 6 BAND_D D CUSTOM 5362 5399 5436 5473 5510 5547 5584 5621
vtxtable powerlevels 5
vtxtable powervalues 25 100 200 400 600
vtxtable powerlabels 25 100 200 400 600
# master
set gyro_lowpass_hz = 0
set gyro_lowpass2_hz = 0
set dyn_notch_width_percent = 0
set dyn_notch_q = 250
set dyn_notch_max_hz = 450
set dyn_lpf_gyro_min_hz = 0
set acc_hardware = NONE
set acc_calibration = 48,33,92,1
set mag_hardware = NONE
set baro_hardware = NONE
set min_check = 1010
set max_check = 1990
set serialrx_provider = SBUS
set sbus_baud_fast = ON
set blackbox_p_ratio = 64
set dshot_idle_value = 600
set dshot_bidir = ON
set ibata_scale = 100
set beeper_dshot_beacon_tone = 3
set yaw_motors_reversed = ON
set osd_vbat_pos = 2488
set osd_warnings_pos = 14601
set osd_disarmed_pos = 2282
set debug_mode = GYRO_SCALED
set name = AOS 3.5
profile 0
# profile 0
set dyn_lpf_dterm_min_hz = 0
set dterm_lowpass_type = BIQUAD
set dterm_lowpass_hz = 110
set dterm_lowpass2_hz = 0
set p_pitch = 110
set i_pitch = 180
set d_pitch = 78
set f_pitch = 190
set p_roll = 100
set i_roll = 170
set d_roll = 72
set f_roll = 180
set p_yaw = 108
set i_yaw = 180
set f_yaw = 180
set d_min_roll = 0
set d_min_pitch = 0
set idle_min_rpm = 30
rateprofile 0
# rateprofile 0
set rates_type = ACTUAL
set roll_rc_rate = 20
set pitch_rc_rate = 20
set yaw_rc_rate = 54
set roll_expo = 54
set pitch_expo = 54
set yaw_expo = 54
set roll_srate = 67
set pitch_srate = 67
set yaw_srate = 67
# end the command batch
batch end
Any thoughts on 6S low kv for this frame? I mean if I don't necessarily want to aim at sub250g at this point and have some 6Ses at hand. Thanks!
No harm in giving it a go. Provided it's not too heavy it should fly fine.
The camera dimensions of the vista or origibal air unit are 27,4 × 21,1 × 20,1 mm, are these fitting into the frame?
Yes. Absolutely. The frame fits the DJI camera and 19mm cameras.
Any idea whats amp draw want to try liion
Hello Chris. Quick question: if I put the things of a Protek35 on this frame, would it perform?
(BeastAiOF745a, Xing 2203.5 3600kv, Vista, 4S)
It’s for freestyle purposes🤣
Absolutely! That would be a good setup for freestyle no doubt.
@@ChrisRosser good! I’m in doubt if the board fits in the frame? Also my 4 S lipos are 1300 , maybe to heavy?
@@whatsnext___ the board fits perfectly, I'm using it in my AOS 3.5 and you'll probably want 4S 850Mah rather than 1300 for freestyle.
Hey Chris! I need some spare arms for my AOS 3.5. I know they’re out there in some shops in EU, can you tell me where to order? Thx!
Hi Chris,
I have a JHEMCU GHF420AIO FC/ESC. It's a 20x20 mm board, 30mm wide and 37.5mm long. Would it fit into the AOS 3.5?
Cheers
btw. Great work. I really appreciate your scientific approach to developing a frame.
I don't think so. That is basically a 30x30 board with 20x20 mounting.
what are flight times like for this build if you are mostly just cruising?
5-6 minutes easily.
Would this frame work with 2203.5 motors? I know it will probably pass the 250g mark but that is fine
I think they would be too big. I recommend 1505 ish for this frame.
I have a query hopefully someone could help with please.
Does anyone know what size screws are needed to build this frame?
I purchased it a while back from cncmadness / cncdrones and I've just tried to put it together but it seems like they accidently included the wrong screws because they are too short. I only have 2 countersunk screws that are of a suitable length for the arms and the base plate.
I'm based in the UK so I was hoping I could just buy some appropriately sized screws from somewhere.
I'm looking to get this frame the only concern being the offset of the flight controller since it's not in the center of the frame does that effect the flight characteristics?
Not at all. The rotation measured by a gyro is the same everywhere on a quadcopter frame. 👍
@@ChrisRosser awesome
@@ChrisRosser will it hold a regular 20x20 stack or just the aio ?
Hi Chris, planning to build AOS 3.5 and would like to know if you would recommend 1505 3450KV also paired with 55A AIO and vista unit? Thanks
I would, yes.
@@ChrisRosser Nice, thanks!
Will you be offering a suggested tune for this frame and loadout?
I will be showing off my tunes at some stage. But I don't recommend you to copy someone's tune, better to tune the quad yourself.
@@ChrisRosser Yes but I would like to see what's theoretically achievable on this well designed frame.
I have since built and flown my AOS frame. With only RPM filtering the backbox gyro filtered chart is perfectly flat above 60hz. It really is an incredibly quiet frame. I don't think there will be any issues obtaining a very impressive tune. Well done!
A _great_ price for this design, too. Will you be offering this with your new arm CF?
Ain't this a great hobby? Not only do we have to worry about burning our houses down, we gotta worry about components de-soldering themselves. . .
I need to test to see if the layup gives an improvement with the V shaped arms as its mainly designed for straight arms. If it does then you bet!
@@ChrisRosser I've been looking at the 3.5" to move up to, and when I do, it's going to be this frame, for sure. It'll likely be the cheapest build in terms of components, but I'll have a beast of a foundation.
Hey Chris, I've noticed my frame: ruclips.net/video/bSpD7fuXXVI/видео.html and the others I've seen on RUclips, have the arms cut with the carbon opposite to your design. Was this a design change or were they cut improperly? I don't think it will be a problem for me, but it was pointed out to me and now I'm curious. Absolutely excellent frame!
If it's at 90degrees don't worry. The performance at 0 and 90 is the same for standard layup. The arms will be cut in different directions to best use the sheet and minimise waste.