Here are some things to be aware of and tips for building my Manta mini quadcopter.

Manta is a 200mm class quadcopter frame I designed for freestyle and racing to use 5 inch props and be balanced when mounting a HD camera. To minimize inertia in the pitch axis I kept the body short, and to balance the center of gravity vertically the battery mounts on the bottom with the HD camera on top. It is a true X design, meaning the motors are equidistant from the center and each other.

This is a bottom battery design, it’s more exposed and probably not ideal for a first quad or somebody at the beginning of their learning curve. Once you have mastered basic flight and are usually landing on purpose the exposed bottom battery is not much of an issue.

The props are in view of the FPV cam. I personally like that but some people don’t. The props are not in view of the HD cam, the tilt angle should be enough to keep them out of sight.

The FPV camera mount plates are designed specifically for the HS1177 case style. It fits best to use a version with the connector at the bottom, the top connector version will fit, but may not tilt up quite as far. If you use less than 50 degrees tilt it probably doesn’t matter. If you want to use a different camera type, consider a different frame. I often don’t even use the screws for the camera, the plates hold it pretty tightly. To add a really nice amount of friction that’s still easy to hand adjust for tilt angle, I smear a thin layer of hot glue on the sides of the HS1177 case and let it cool, so that it grips the smooth carbon plate nicely and doesn’t slip even without screws. Some cam bodies have a bit of plastic that prevents the side of the camera to be flush against the CF plates. I clip that plastic or shave it down so the entire side of the camera is against the plate, otherwise there isn’t enough friction to hold the cam tightly and it may change tilt on it’s own.

The VTX mounting is designed to require removing the SMA from the VTX and replace with a very short pigtail, so the VTX can mount horizontal in the stack with the SMA vertical through the top plate. The props are very close to the antenna if it’s mounted straight out the rear instead of vertically on the top plate. I find it simple to replace a SMA but some people may not. Here is a picture of the VTX with a short pigtail SMA. Because the VTX is mounted in the stack, I recommend avoiding DIP switches to change frequency. A VTX with a side button such as the ET200 has is ideal, but something like a FX799 should fit although some tool or even a prop blade would probably be necessary to reach the button. I use an ET200R and can see the LEDs from the top and reach the button from the side without tools to change video frequency.

The RX needs to be a fairly small one, I use a FrSky X4R without pins, or the XSR. I find it easy to depin an RX but some people may not. Some places sell X4R naked without pins. The XSR does not need depinning. When I mount the RX above the top plate I remove the X4R pins and solder a 4 pin pigtail to stick out the bottom back of the mount, and solder an opposite gender pigtail to the FC, so I can easily just unplug when removing the top plate. Here is a picture of how I prepare my RX above the top plate. If you are comfortable doing extremely tight builds, it’s possible to mount the RX below the top plate and leave the top of the quad clean if you will not be using any HD cam and want a light super high performance build.

The HD cam mounts are 3D printed with a flexible plastic that is very durable, but messy to print with. Even after I clean them up by hand they don’t look perfect but they are very functional. Right now I have HD cam mounts for Mobius, Yi, GoPro and GoPro Session. I attach the mounts to the top plate using 2.5mm zip ties. Using 4 seems to be enough for the larger HD cam mounts, but there are holes in the top plate to allow using more. The zipties act as mechanical fuses, and in a hard crash will let the camera separate from the top plate which usually results in less damage. In my testing, 2 zipties were a little too easy to break and separate the mount in a crash, but 4 seemed about right. My goal is for a crash hard enough that damage to the camera is a concern to break some but possibly not all the zipties, and a hard crash to separate the cam from the frame completely. The front and back ziptie holes are wider to fit 4mm zipties, which is also helpful for using zipties as antenna supports if not using any printed mount.

Using one of the printed antenna/RX mounts is required if you don’t mount the RX below the top plate, even if you do not actually use a HD cam. The receiver mounts above the top plate inside the cam mount which also has antenna mounts intended for Capri Sun straws or similar. The Mobius mount is the small and will be included with every kit, so that’s the one to use if you don’t fly a HD cam, think of it as a receiver and antenna mount that a mobius size cam can just happen to fit onto. I do have an even smaller mount without the wedge if you must mount the RX above the top plate and do not need a camera wedge, but I recommend you fit the RX under the top plate if you can if that is the case.

The XT60 should be ziptied to the tab on the frame so there’s no chance of long battery wires getting in the props. For this to work well, make sure the XT60 is positioned so it covers the entire tab. This way a single ziptie is enough and can’t wander off either end of the XT60. Most 36×36 standard PDB should fit fine, I have been using this one for months on several builds with no problems, it has dual power and current/voltage sensor outputs.

About zipties… I use them a lot in my designs for few reasons… They can serve as mechanical fuses and allow crash energy go into breaking them instead of other more expensive components. They are lighter than many other fasteners, and they are easily replaceable in the field. However, they often need more than hand-tightening to be most effective. I cinch them down using needlenose pliers by gripping the tail right against the head and rotating the pliers, using the leverage of the grip pushing against the head to get a few more clicks out of it. Don’t overtighten as that can weaken the tie, but when the tie is flat against all surfaces with no slack it makes a very good fastener.

Most of my builds use a BrainFPV flight controller, which has an onboard OS. I have done a build using a separate OSD and am able to fit a MinimOSD board behind the HS1177 without difficulty. There are also flight controllers that have onboard OSD for Cleanflight and other firmware that should fit fine without needing a separate OSD. The standoffs are 30mm, which can’t be changed without also changing the camera mounting plates, so be aware your stack size needs to fit within this space.