FPV Frame

Frame Job

The frame holds all FPV drone parts in the right position:

Motors and propellers
Flight controller and ESC stack
Battery
FPV camera and video transmitter
Receiver, antennas, GPS, buzzer, and action camera

The frame affects flight feel, crash strength, vibration, camera view, prop size, and how easy the build is to repair.

Frame Types

FPV frame geometry examples

Frame type	Best for	Pros	Cons
`True X`	racing, freestyle, general 5 inch builds	Balanced motor spacing, similar roll and pitch feel, easy to tune	Props may appear in HD camera view
`Stretch X`	racing, fast freestyle	More pitch stability and forward-flight feel, good for cornering	Less symmetrical than True X, can feel different on roll vs pitch
`Squished X`	compact freestyle, some cine/freestyle builds	Wider side-to-side motor spacing, compact length	Less pitch authority than Stretch X, props can still be visible
`Deadcat`	cinematic FPV, HD camera builds	Front props are usually out of camera view	Asymmetric layout, yaw and tuning can feel less clean on some builds
`H frame`	long range, payload, roomy builds	More space for battery, camera, VTX, GPS, and wiring	Longer arms or heavier center body, usually less agile
`Plus`	simple experimental quads	Simple motor layout and supported by Betaflight	One motor is directly in front of the camera, uncommon for modern FPV

Note

A physical Deadcat, Stretch X, or Squished X frame is often still configured as QUADX in Betaflight. The mixer describes motor control geometry, not the marketing name printed on the frame.

Material

Most modern FPV frames use carbon fiber plates because carbon fiber gives high stiffness and strength for low weight.

Common materials:

Material	Use	Pros	Cons
Carbon fiber	Main plates and arms	Light, stiff, strong, good crash resistance	Conductive, sharp edges, dust is unsafe when cutting
Aluminum	Standoffs, camera cages, hardware	Strong threads, easy machining	Heavier than plastic, can bend, transmits vibration
Steel	Screws and press nuts	Strong, cheap	Heavy
Titanium	Premium screws or hardware	Strong and light	Expensive
TPU	Antenna mounts, camera bumpers, GPS mounts, arm guards	Flexible, absorbs impact, easy to print	Too flexible for main arms
Plastic / polycarbonate	Ducts, whoop frames, camera protection	Cheap, light, impact tolerant	Less stiff than carbon, can cause vibration on larger builds

For 5 inch freestyle, a common starting point is carbon arms around 5-6 mm thick, with thinner top plates around 2 mm. Racing frames often save more weight. Long-range frames usually prioritize stiffness and lower vibration over crash strength.

Frame Size

Frame size normally means the largest propeller the frame can safely use.

Prop size	Common use
`2-2.5 inch`	tiny whoop, micro indoor, lightweight park flying
`3-3.5 inch`	small freestyle, sub-250 g builds
`4 inch`	efficient lightweight freestyle or long range
`5 inch`	standard freestyle and racing
`6 inch`	cruiser, heavier freestyle
`7 inch`	long range
`8-10 inch`	heavy long range, payload, efficient cruising

Larger frames usually carry larger props and bigger batteries, but they are heavier and need more space to fly safely.

Selection Factors

Check these before buying a frame:

Prop clearance: the frame must fit your prop diameter without the props touching the frame, camera, battery strap, or wires.
Stack mounting: common sizes are 30.5x30.5 mm, 25.5x25.5 mm, and 20x20 mm.
Camera mounting: check analog micro, DJI, Walksnail, HDZero, or action camera support.
Motor mounting: common small motors use 9x9 mm or 12x12 mm; 5 inch motors often use 16x16 mm.
Battery space: long top plate or bottom plate space matters for LiPo size and center of gravity.
Arm design: replaceable arms are easier to repair than unibody plates.
Arm thickness and width: thicker and wider arms are stronger and stiffer but heavier.
Carbon quality: poor carbon can delaminate or vibrate more.
Vibration path: soft camera mounts and clean arm design help the gyro and video.
Electronics protection: side plates, camera cages, and TPU bumpers help protect expensive parts.
Weight: lighter frames feel sharper and fly longer, heavier frames usually survive crashes better.
Access: check if you can remove arms without taking apart the whole stack.
Hardware: use good screws, threadlocker on metal-to-metal screws, and avoid over-tightening carbon.

Unibody vs Replaceable Arms

Design	Pros	Cons
Unibody	Light, simple, fewer screws	One broken arm can require replacing the whole bottom plate
Replaceable arms	Easier and cheaper crash repair, common on freestyle frames	More screws, more weight, possible arm slop if hardware loosens
Sandwich arms	Strong arm clamping between plates	More parts and stack height

For learning freestyle, replaceable arms are usually the practical choice.

Betaflight Support

Betaflight supports built-in mixers and custom motor mixing. Use the Betaflight Configurator or CLI:

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mixer list
mixer QUADX
save

Common Betaflight airframe mixers:

Mixer	Meaning	Typical FPV use
`QUADX`	Quadcopter X	Most FPV quads: True X, Stretch X, Squished X, Deadcat
`QUADP`	Quadcopter Plus	Plus-shaped quad
`TRI`	Tricopter	3 motors with a yaw servo
`Y4`	Y4-copter	4 motors in Y layout
`Y6`	Y6-copter	6 motors, coaxial Y layout
`HEX6`, `HEX6X`, `HEX6H`	Hexacopter layouts	6-motor builds
`OCTOX8`, `OCTOFLATP`, `OCTOFLATX`	Octocopter layouts	8-motor builds
`VTAIL4`, `ATAIL4`	Tail quad layouts	uncommon experimental frames
`CUSTOM`	User-defined motor mix	unusual motor positions
`CUSTOM AIRPLANE`	User-defined fixed wing	fixed wing, not normal FPV quad
`CUSTOM TRICOPTER`	User-defined tricopter	unusual tricopter layouts

Summary:

Most modern FPV quad frames use QUADX.
Frame marketing names like Deadcat or Stretch X usually do not require a special Betaflight mixer.
Use CUSTOM only if the motors are not close enough to a normal X mixer or if the frame has a special geometry.
After changing frame type or mixer, always verify motor order and motor direction before flying.