Following the introduction of the new range of square drive arcuate and pantograph windscreen wiper arms, the opportunity was taken to further enhance the performance by introducing a new slave arm swivel post to replace the earlier version that attached to the slave arm by way of a collet nut. This collet nut was sometimes difficult to access for tightening purposes, engaged on a 6mm diameter spindle that rotated within the body of the slave post. By comparison the new slave post is a fixed stainless steel component over which the head of the slave arm rotates on a bearing that is located within it. The fixed spindle of this new slave post has been increased to give a bearing diameter of 12mm.
6mm diameter
Swivel Shaft
12mm diameter
Fixed Shaft
The adjacent illustration shows the earlier style 6mm diameter slave arm swivel post alongside the new 12mm diameter fixed swivel post. The slave arm of the pantograph assembly which swivels on the fixed post is held in position by a retaining bolt and corresponding washers that is tightened to a torque of 17 Nm.

The male thread that is used for fixing to the bulkhead is the same on both old and new types and as such it is a simple process to substitute the old slave post with the new slave post.

Old Style
New Style
Slave Arm
12mm diameter
Bearing for Fixed Slave Post
Square Drive Main Arm