Servo shear screw

Post here anything about a more technical nature not directly related to a product - installation questions or solutions, anything you think may help others as well. Floobidust - a term sometimes used by us nerds to categorize anything that does not fit into a category. Sort of a wild card.
Forum rules
Please keep your posts friendly and on topic. No politics or discussions of a controversial nature not related to our favorite subject of flying and avionics. Offending posts may be removed or moderated.
Post Reply
pavel569
Posts: 5
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: 701
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.
Post Reply