I've often said that there's not a lot of innovation going on in the world of quadcopter frames. Most quadcopter frames are largely derivative of frames that have come before them, and then every so often you've got a frame that comes along and does something truly original. Well, today we're looking at one of these frames that does something truly original.
This is the RubberQuad's Squirrel, and you can immediately see what makes it so interesting. The frame is not a traditional split-deck design where you've got a bottom plate and a top plate. Instead, the electronics are sandwiched inside these two plates, which are just the height of the arms and basically nothing more.
It's a little hard for you to see here, but the flight controller is a 25mm all-in-one flight controller and ESC. That means the flight controller and ESC are on a single board. And normally I might complain about that because they have less durability than separate flight controllers and ESCs. and if you blow one of them, like you blow one ESC, and suddenly you're replacing an $80 or $90 board.
But I think it's okay in this case. Up to about the 3-inch or 3.5-inch size class is right about where I feel comfortable using an all-in-one flight controller. Much larger than that, and I would insist on a separate flight controller and ESC. The Squirrel mounts an O3 air unit in the rear of the quad, and you can see here they've got it mounted vertically. That allows it to fit...
down in between the props which helps keep the weight centralized and presumably improves the handling you can see here that there's very little room to spare and if they had mounted it the traditional sideways way they would have had to figure out a much more complicated way of pushing it upwards i'm also really impressed that they have used a usb extension board here this is the usb cable for the flight controller and it means you don't have to try and like fish a usb cable into the guts of the machine in order to configure the flight controller very smart The motors are rubber quads brand. That's interesting. I didn't know rubber quads had their own brand of motors. They are 1604 size at 4040 kV. That 16 millimeter motor is larger than you might see on a smaller, well, I was about to say lighter.
Normally I think of 16 millimeter motors as being for three inch and three and a half inch quads that are going a little over 250 grams, maybe in the 280 to 300 gram range. Those heavier quads really require the larger motors. And in order to get the torque they need and just to deal with the heat buildup because they're working so hard. I can only imagine that a 1604 motor on something like this that's going to come in under 250 grams is really going to handle very well. The weight of the quadcopter by itself is 172 grams and with this battery it comes in, oh my goodness, 247 grams just under the 250 gram threshold.
I don't need to register this with the FAA, isn't that nice? I do need to register it with the FAA because it's part 107 operation and I have to register everything. Anyway, that's not the point. The battery that we're using is this 650 milliamp hour dog comm battery.
Uh, yeah, so, enough said. Let's go out and fly it. Let's see what we got here. This little booger.
It's fast. I'll hit myself in the head with it. Is it a racer?
Oh, it picks up speed. It's not the fastest three inch I've ever flown but You could definitely race it I thought about diving into that hole but decided I don't want to destroy it just yet. Where am I standing? This is not...
I don't... I shouldn't have great range from here. Worked out okay.
Oh this is fun. Man, I freaking love this size. The power is so good.
And it doesn't feel like you have crazy consequences. Like with a five inch, if you crash it, it feels like the consequences are super real. And on a three inch or three and a half inch, it just kind of feels like it doesn't matter. I don't know why. They're more durable.
And it just makes you want to freaking cut loose. Just makes you want to cut loose and fly it anywhere. Whee! Jeez. This is so fun.
Oh my god, it's so fun. It's just the right combination of speed and agility. It just makes you want to cut loose.
Nice, nice. Oh my god. How's the battery doing?
3.7? Ha ha! Oh hey! Oh, ah, oh.
Okay. Oh hi, daddy long legs. Okay, I think I broke a prop. Oh boy.
Oh, that's a lot of branches. Okay, that's good. That's good.
That's encouraging. Okay, I think we're gonna go walk and get this one. We're not gonna try and turtle out of there.
Oh, well, shit. Well, that's short review. I was having a lot of fun.
I was really looking forward to picking the quad up, maybe having a broken prop or something, and getting back in the air and continuing to have fun. But, alas, it is not to be the skinny... What is that?
I don't know. That's skinny. How did it break?
It's good to say it's skinny, but it's only skinny because it sheared off at the end That's like that's probably three millimeter. I would guess I don't think it should have broken like that. Look here I mean do you see how it didn't like tear and splinter off it?
It delaminated. It separated at the layers and shredded out. That's not how carbon normally breaks in my experience. You know what? I changed my mind.
I was having so much freaking fun flying this thing. And this is actually a loner bird that kind of gets passed around from YouTuber to YouTuber. I can't be sure that that was actually a brand new arm. And that had already taken a million hits.
This quad deserves another chance. So what let's do is I'm going to put a spare arm. I actually complained.
to the creator of the frame and he said, can I just send you a spare arm? And I was like, okay, I'm gonna put a spare arm on. We'll see what this is like to change an arm, how fricking complicated that turns out to be.
And then we'll take it out and we'll fly it some more. It was really fun to fly. And it looks to me like the arm goes, and I see.
So these, I'll flip it over. These, one, two, three, four here. the arms go in like that and the arms you can see they overlap and so these screw holes here are what's holding the arms in so we'll just remove two of those screws and the arm should come out is it not a 1.5 millimeter the it's a torx what what okay but what I acknowledge the sort of objective superiority of Torx connectors.
Torx connectors are amazing. But why? I dislike having to pull out a different tool kit.
because you couldn't use a hex screw like freaking everybody else did we really need a torx connector right now shoot uh this screw that i need to remove to get the arm off is not accessible not really is it can i get in there i could try to take the entire back section off yeah you've got these tabs here and here so And it sure seems like in order to take this back section off, I'd have to remove this entire plate and release. Well, the whole thing would fall apart. I don't want to do that. That's a lot of work just to change an arm.
Like, I understand you may... some compromises on these smaller frames in the interest of compactness but it sucks i mean i'm not i'm not gonna say i could come up with a better way to do it i'm just gonna say you know from the perspective of someone who's living with the frame it sucks to have to go to all that work just to change an arm hmm oh man looks like we also ripped off one of the motor wires that's a shame and again not looking forward to taking this whole damn thing apart to get at the flight controller I'm gonna see if I can solder it down just by sort of squiggling in there well yeah who's the man it's because they're countersunk that's why they're torques it's because they're countersunk i realized it as i'm putting this one in i noticed that these are countersunk screws so they sit flush with the carbon and so are these although I'm not 100% sure why I guess it keeps them clear of the battery pad so that doesn't dig into the battery and I'm gonna guess that it's not no I can't think I've ever seen a countersunk m2 But maybe then it's just the screw heads are not durable enough and they went with torques instead because it's a more yeah, okay I guess I see why All right. Well moment of truth.
I may as well catch it on camera. Is she gonna smoke? If I were smart I'd use a smokestopper Am I smart?
Can't find my smokestopper No smokestopper no smoke Okay, so far so good Telemetry connected. Good sign. Oh, throttle's up.
Oh, okay. I guess it's fine. Let's take it back out and fly it some more.
I suppose I should continue to durability test this a little. And it'll be easy to do that because I'm just going to be motivated to have a great time with how much fun it is to fly. Oh look at that! Look at that!
That was almost a trippy spin. Can I trippy spin? Not a trippy spin.
Oh, battery moved. It's a good thing I didn't get up and fly. I would have flipped my battery up.
Let's not just spend the entire flight trying to trippy spin and crashing. Oh, you know what I want? Come on, get up. You know what I want is, I want to back flip through here.
Okay, ready? Nice. That's more like it. That looked good. Oh, that looked real good.
I like that a lot. All right, well, I broke a prop so I can't keep flying. But before I go back inside, I got to do one more durability test and see if it can take the fall from the top of that tree again.
From about here, I guess. And... Oh, cheating! You can't land in a tree! You gotta hit the ground!
Okay, take her easy for a second there little fella. Take her easy there. Okay, for real this time.
Seems okay. No harm done whatsoever. Come on. Yeah.
Well, it's in the grass, but... Okay, we'll leave it at that. I'm done beating it up.
There's no reason to go insane. Wow. I'm really glad that I gave this a second chance and didn't just write it off because the arm broke.
I guess it was a fluke or it had been hit before because it wasn't brand new. I dropped this thing from the sky a couple times, as you saw, and no damage was done. So everything gets unlucky eventually, and maybe that's what it was.
We can tell from looking at this that this is not an ultra-durable bando basher. Like... The arms are not that thick in the width dimension, and if we look at them in the height dimension, they are plenty thick. This is a great thickness for a quadcopter of this weight, but they have a weak spot here where they come together, and they're only half height.
And I'm pretty sure that's where they broke in the other fall. They sort of sheared and split at that dimension, that location. It does look like this is just a single piece of carbon fiber, like there's no, like... Sometimes you'll see a piece of carbon fiber and it looks like they took... two pieces and glued them together and that does not appear to be what's going on here this just looks like one piece it's just milled away here at the ends to half height and that creates a weak spot but everything's got weak spots everything breaks somewhere and there's always a trade-off between weight and dirt ...ability and this quadcopter seems to be leaning more towards lightweight than ultimate durability.
That being said, I don't think the durability is particularly bad, especially for quadcopter of this weight. The other weak spot I think is gonna be the motors, right? This style of motor with the 2 millimeter shaft and the wider bell It's always a little bit more likely to bend But in all the bashing you saw me do out there, the motors are still working. In fact, I guess what I should do is put on a fresh set of props and just see if it smooths back out again. It was pretty janky toward the end.
I don't think that's because any of the motors are off balance, though. They don't show any resistance or anything like that. They're fine. It's just...
I think that the props got a little janked up. That's what he's going to do. That just happens. I love the way that the quack protects the O3 camera. The O3 camera is, well, first of all, if you break the lens on the O3 camera, it's a hundred bucks for a new camera.
You can't just replace the lens, at least not without doing some really extreme surgery on the camera. People have done it, but it's not like they just sell a lens that you screw out, you screw a new one in. I love the fact that the camera is perfectly adjustable.
We can adjust the camera's depth. So you can set the camera exactly where it needs to be so it's not taking hits. Well, it's as protected as it can be from hits.
Nothing's perfect, but I love that we can get the camera exactly where we need it to maximize the durability. I guess if I had one criticism about the design, it would be that the battery moves a little too easily in a crash. So here you can see we've got some It appears to be a fairly grippy battery pad too. It is not the sort of harder battery pad that provides padding but not any grippiness.
I'm not sure why the batteries were moving. I wonder if maybe we needed like a fresh piece of... I always used Umagrip, which is the original super sticky battery pad.
I also... Oh! Oh!
Oh! Somewhere Tommy's heart is breaking. Because inside my umma grip is, oh, there's the real umma grip.
See, it is umma grip. But also some rip-off Flywoo umma grip. Well, umma god was the original person who came up with this formulation for the super sticky battery pad.
But it's not like, you know, he invented it. It's just... some polymer and so other people are like hey we can do the same thing anyway i might want more battery pad or i might want like a fresher battery pad the thing is it kind of wants to be custom cut to allow access to the screws so just slapping a piece on there would have its own issues but especially with as much clearance as this has which is not much i mean if the battery moves in a crash it gets kind of chewed up which in fact happened to me so there you go i guess the other criticism I would have of this, and it's not really a criticism because it's kind of inherent to what it's trying to be.
But the other criticism I would have is that it's maintainability. It's kind of a hassle. Like if you end up having to solder something into the flight controller, you may end up having to tear the whole thing apart. And basically you're just going to end up with it all falling apart. It's not very maintainable.
And that's not as much of a criticism because like for a quadcopter of this size and of this weight, you have to make some sacrifices to get the weight down. And that's one of the things you do. It flies amazing.
I really enjoyed flying it. And part of that has to be because of what they've done with the CG, putting the CG in line with the prop and so forth. It flies amazing. And so I don't feel like it's complexity for complexity's sake. I feel like it's actually servicing a goal.
And if what you're looking for is... Oh, that got jammed in. I wonder if that was always like that.
If not, it should have been. That'll increase the durability too. If what you're looking for is a sub 250 gram, three inch that flies really great, I feel like this is a good choice.
Yeah, it's hanging in there. it's hanging in there it's gonna loosen oh well that's not as tight as it once was yeah that's loosening up a little bit okay i'm gonna tighten that screw can you tighten that screw will that help where does that even go oh yeah that's better tighten it up this This is not like a Grindrino, which is Botgrinder's little micro. This is designed for performance and less for durability. If that's what you're looking for, it's a pretty cool frame and I've really enjoyed flying it. If you're interested in picking up a RubberQuad Squirrel, there's a link down below to the RubberQuads website.
And RubberQuads is a really, they're not like a giant company churning out frames by the millions. They're a very small designer doing some really innovative stuff. So I'm very happy that they shared this quadcopter with me and very happy to be able to sort of support them by making this video. But if you're interested in seeing a different rubber quads design, I also reviewed the rubber quads. I think it was the Ducky or the Duck.
And it is an older frame with some of the same design goals, but kind of a different way of approaching them. If you like this video, I think you should check that one out too. I'll put a card on screen and a link down in the video description below where you can check it out.