Reinstalling Protective Plastic Sheeting in the Doors

Note: From August 1965 a plastic sheet was cemented to the inside of the door frame to provide better sealing against the entry of water between the inside of the door and the door trim panel. Appropriate plastic sheeing can be purchased at any hardware store (e.g., 2.0 mil plastic drop cover).

When working inside your doors, you may have found that the plastic sheet which VW so meticulously applied to the inside of the door frames is either hanging in shreds or has disappeared altogether. (I didn't even know such a plastic sheet had been there!)

The culprits who remove this protective sheeting are most likely panel beaters, car radio installers or mechanics who have had to fix a rattle or a tight window. From their point of view, the sheeting is just a bother, and their job does not extend to mucking around with plastic and glue. Besides, the customer doesn’t notice anyway. Most owners and many mechanics don't know what the sheeting is for, and they just rip it out to get it out of the way.

What are the consequences of not properly sealing the door cavity? Rain water, which is able to get past even brand new window seals, will go straight onto the inside of the door trim panels. These panels are made of flimsy pressed fiber board that will buckle, tear and generally flop about when they become wet. Water can also leak through the door and into the car, where it sits for years underneath the carpet and sound deadener, promoting the dreaded iron oxide (rust!).

If the car has had speakers installed in the door panels (a common reason for the seal being broken), water will go straight onto the speaker membrane, which, usually being made of thin cardboard, will beat itself to slush -- bye bye speakers!

The VW designers haven't helped very much, unfortunately. Some other auto makers use a neat and durable plastic moulding which reinstalls without glue. The contact cement which VW used works very well -- it guarantees a good attachment of the plastic sheeting to the door frame. However, when restoring this protective plastic sheet in the door frame, the most difficult part of the job is the contact cement. It's expensive, it goes off in the pot, it can't be re-used, it's hard to apply and hard to clean up, it smells bad, and it takes a long time to cure. And once applied, contact cement works so well that it is easy to rip the plastic when attempting to remove it. And after being removed the plastic sheet can't be restuck on the original contact cement.

So to do this job using contact cement, the conscientious person would need to have at hand the following: some sturdy plastic sheeting, (available at most hardware stores), paint-on contact cement and brush, acetone or MEK for cleanup, scissors, knife, and about half an hour per door. When the purpose of the plastic sheet is not understood, it's not surprising that people don't go to the trouble to do this job.

What is needed is some kind of adhesive which sticks like the proverbial to a blanket again and again, has a long shelf life, is easily and quickly applied and removed, and has no smell. This wonder stuff does in fact exist -- it's called "Blu-Tack". You know, the stuff your teen-age son uses to stick up all of the posters on his bedroom wall.

You can roll Blu-Tack up in your hands into long snake and push it into place exactly where its needed. There is no cleanup (other than washing your hands), no smell, and no curing time. And it's completely reusable -- the next time you remove the door trim and plastic sheet, just roll the Blu-Tack up again into another snake and re-apply when necessary. (Thanks to John Frizza for the Blu-Tack idea.)

Note: When applying the plastic sheeting to the door frame, be that you don't cover up the rubber seals that are pressed into the holes in the door frame. Clips in the door trim panel will be inserted into these rubber seals. Again, see our Door Trim Panel Installation procedure. Also, you should be especially generous with the Blu-Tack at the bottom of the door trim panel, as this is where water tends to run into the gap between the door skin and the panel and go on to do its dirty work.

Now lets say you have speakers in your door trim. The speaker magnet will push right through the sheet, right? So you'll have to cut a hole in the plastic sheeting to accomodate the speaker, thus defeating the whole purpose of the protective sheeting. The following solution has been suggested to us: borrow your wife's hair drier, set it on its hottest setting, and briefly heat up the plastic behind the speaker without letting it melt through. Then push the plastic inward with your fist to stretch it. You might need to do this a few times so that the correct clearance is created. You'll probably burn your hand in the process, but it's better than the alternative, right? Then poke a small hole in the bottom of the indentation you have created, feed the speaker wire through and let it hang out for connection to the speaker. You can seal the little hole with RTV.

An observation -- if you can afford German Blaupunkt speakers, they have a protective covering to prevent water from above from impinging onto the membrane. Bose speakers, and probably others, also have a waterproof membrane.

1. Remove the door trim panels in accordance with our Door Trim Panel procedure.
2. Perform any work that needs to be done inside of the doors (e.g., windows, regulator repair, felt channel installation, etc.).
3. Cut a piece of plastic sheeting slightly larger than the door frame (from just below the window opening to the bottom, and side-to-side).
4. Roll some Blu-Tack between your hands to make a long snake.

Note: Also called "Paper Tak," this is an adhesive mounting putty that adheres to most clean, dry, non-porous surfaces like glass, tile, lineoleum, metal, mirrors, plastic or porcelain. It's commonly used for attaching posters and light-weight pictures to walls that you don't want to ruin with holes.

5. Apply Blu-Tack across the top of the door frame below the window opening, making sure that it is applied in one continuous piece.

Note: Note the locations of the holes in the frame into which rubber inserts will be pressed, and into which the door trim panel clips will later be inserted. Apply Blu-Tack around these holes so they will be exposed after you trim the plastic sheeting.

6. Press the top edge of the plastic sheeting firmly into place along the top of the door frame, just below the window. Allow a little extra across the top (you'll trim it back later in the procedure).
7. Apply a bead of Blu-Tack around each of the openings in the door frame through which hardware (e.g., door handle, window crank, arm rest, etc.) must pass.
8. Press the plastic sheeting into place over these openings (you will cut out the openings later).
9. Apply a bead of Blu-Tack along the sides and across the bottom of the door frame, being especially generous across the bottom. Make sure there are no gaps.
10. Press the plastic sheeting firmly into place along the sides and across the bottom, so that it is now firmly attached all the way around, with no breaks.
11. With a sharp pair of scissors, cut holes in the plastic for the hardware that will extend into the frame, making sure that the plastic is sealed to the frame around the holes with Blu-Tack.
12. Cut off the excess plastic sheeting all the way around the door frame. Be sure to trim around the holes for the door trim clips, and make sure that the plastic is sealed around these holes with Blu-Tack.

13. Install the door trim panel per the Door Trim Panel procedure.
14. Do the other door.