Sunroof drains


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.


3D printed drain plugs can be created from two STL format files:


These .stl files are calibrated in inches and most 3D printers should be able to fabricate plugs from them without any modification. A good third party 3D print vendor is Craft Cloud 3D and their approximate cost is $10-15 per plug for inexpensive PLA, ASA, ABS, and PETG plastics (you need two for left and right, so the total cost should be under $30 plus shipping). Nylon is probably the best material, but more expensive.

Please note that these files remain the intellectual property of Kriss Motors Corporation and are being made available as downloads exclusively for personal non-commercial use only without warranty or support. Copies of the files, or products made from them, cannot be sold or distributed in any manner. Any installation, modification, or fabrication is entirely at user’s risk.


Channel cut around sunroof rail

Refer to the substructure, drain hose, 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

For the final installation, use an appropriate metal/plastic glue and secure the drain plug with a small set screw.

Secure the drain plug with glue and a small set screw

The set screw provides more stability for the drain and also acts as a stop for the sunroof step motor. The design of the drain plug insures that the sunroof will not hit the back of the cab surround.