Servo shear screw

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pavel569
Posts: 4
Joined: Sun Sep 27, 2020 7:05 pm

Servo shear screw

Post by pavel569 »

I've just ordered a second autopilot servo for pitch control. In order to make a mount for it, I've removed my old one to get the proper measurement, placement or so and I found out that the shear screw is not original (the servo was bought second hand) but most likely brass with flat bottom instead or flat head. Can I get an info about what material and chamfer angle to get?
Thanks, Paul
rainier
Site Admin
Posts: 647
Joined: Fri Aug 28, 2020 7:03 pm

Re: Servo shear screw

Post by rainier »

We found that standard countersunk M3 (Metric) solid brass screws have just the right properties - shears clean at about 10Nm (on outer hole) and does not suffer from fatigue. Avoid mild steel screws. Stainless steel can be considered but not as good as brass. Make sure your screw is solid brass and not plated brass.
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