Design Improvements for the Zenith 601 HDS: Toe Brakes

Toe Brakes

To improve the effectiveness of the toe brakes, the actuators of the brakes have been redesigned. Goal was an increase of the pressure exerted on the pistons of the brake cylinders. The increase has been so chosen that it still is impossible to lock up the wheels on dry pavement.

In the new design, the bottom of the brake cylinder is close to the bottom of the rudder tubing, the "T" of the toe brake is extended, two triangles are attached to the "T", and a "U" bracket is added that converts the downward rotation of the triangles into a straight motion depressing the piston of the brake cylinder.

The original hinge of the "T" has been extended by a bit of tubing, and a longer hinge pin is used. The top of the "T" is extended correspondingly.

The increase in force depressing the piston is decided by the ratio of the height of triangle divided by the length of the shortest side of the triangle.

Note that the design requires that a remotely mounted brake fluid reservoir is used. Such a reservoir is highly recommended. First, if the reservoir is mounted close to the oil tank on the firewall, then the fluid level is readily examined as part of the preflight check. Second, the reservoir is easily refilled if needed. Last but not least: Thanks to my friend Les Palmer, who helped patiently with the design and implementation.