Background

Sunroof Beetles have drains at the front and rear corners that are connected to tubes running down the A and C pillars. When the rear section of the Beetle roof is removed, a new drain setup is required.

VW rear sunroof drain plug with tube outlet facing the back

To maximize sunroof movement, the tube outlet must be moved 90-degrees from back-facing to B pillar facing. Surgery can be performed on the original part, but a complete re-design of the drain plug is a more elegant solution.

3D printed drain plug

Revised sunroof drain plug design

The plastic drain plug snugly fits into the aluminum sunroof rail.

A revised 3D printed part incorporates two elements: a side-facing tube outlet and an end bumper to stop sunroof movement. This adds about one inch of sunroof movement by efficiently changing the tube outflow direction.

Installation

Channel cut around sunroof rail

Refer to the substructure and roof skin cut discussions.

Prepare the sunroof rail by trimming along the support bolt that secures the rail to the roof substructure, and then angle forward towards the rail end; leave an extra length that will be trimmed to fit.

Trimmed rail end (left side)

Trim around the rail until the 3D drain plug fits just under the support bolt.

Correct drain plug fitment under support bolt