On Jun 16, 10:56*am, Itsaplane wrote:

This is a TOST drum brake.

Should I investigate this further?

I'd assume that whatever was buzzing either died or escaped.

Perhaps some rusting of the brake drum caused a resonance which went
away after the rust was polished off. How long since the last brake
usage and is the glider in a damp environment?

You could try disconnecting the brake cable so the actuating arm is
fully relaxed and see if the rubbing goes away. If it does not, you
may need to pull the wheel and inspect the brake plate, shoes, and
drum. If it does, you may need to adjust the cable or the arm
position. The best geometry is for the arm and cable to be just short
of a 90 deg angle at max brake application and the shoes should not
rub when there is no brake application.

I always applied full brake as the wheel spindle bolt was tightened.
This ensures the brake plate is centered if there is any free play.

I'm assuming you dismantle it every year and clean and lubricate the
pivot points and the cam faces.

Andy