Motor Screw Torque Guide — Why Stripped M3 Screws Are Killing Your Efficiency
Stripped M3 motor screws are the most common installation problem I see in group chat. Someone posts a video of a motor spinning rough and the diagnosis is always "bad bearing" — until I ask them to check their screw torque and it turns out the motor is moving on the plate.
The Problem With Overtightening
M3 screws into aluminum motor mount plates have a torque window of about 0.5 N·m. Too loose: motor shifts under flight load, your dynamic balancing is useless. Too tight: you strip the thread in soft aluminum, and now you need a tap to fix it.
The sweet spot: just snug Improper torque also causes vibration issues that affect your OSD., then a quarter turn more. Not "as tight as possible."
Why Titanium vs Steel Matters
Steel M3 screws are harder than aluminum threads but they are also heavier and can gall — the threads seize under vibration and you end up breaking the screw trying to remove the motor. Titanium M3 screws have better hardness-to-weight ratio and do not gall as easily. Plus they are lighter.
For a 4-motor quad: switching from steel to titanium saves about 8-12g total. Not a lot, but real.
The Right Way to Install
- Clean threads on both screw and motor mount plate
- Apply a small amount of medium-strength threadlocker (blue, not red)
- Torque to 0.4-0.5 N·m — if you do not have a torque wrench, "snug plus quarter turn" is close enough
- Recheck after 10 flights — thermal cycling can loosen screws
The Screw Kit
FPVMotorCo stocks M3x8mm titanium bolts in 20pcs packs — enough for 5 builds. Pre-threadlocked from the factory, so no threadlocker needed on install. Check the accessories section.
FPV Motor Screw Kit at fpvmotorco.com
The easiest way to avoid stripped screws: use a quality hex driver, not the cheap L-wrenches that come with frames. MIP drivers are worth the money. A $20 MIP set will save you more in stripped frame holes than a dozen cheap drivers combined.
Keep Reading
---Looking for pre-tested 6S motors that ship from LA? Check out Motor Screw Kit (Titanium) — every unit bench-tested, backed by 50% crash replacement. 🚀