Door membrane

[f1fascination]

Guys, does anyone know where we can buy sheets of the plastic membrane under the door cards?
And the non-permanent adhesive that holds it to the door skin?

[pancho]

Bunnings.

[njh1964]

You could use something like this plastic film (available from Bunnings - see below link) as a moisture barrier.

http://www.bunnings.com.au/grunt-2m-x-10m-100um-clear-multi-purpose-builders-film_p0810294

As for the non-permanent adhesive, a tube of butyl mastic (also available from Bunnings - see below link) should do the trick.

http://www.bunnings.com.au/selleys-400g-gun-grade-black-butylmastic-sealant-_p1234715

Butyl mastic will form a skin, but stays permanently plastic below the skin.

[f1fascination]

Great stuff guys!

[Norseman50]

This is what I found that appears to be identical to what was in my doors:

http://www.amazon.com/Gauge-Peva-Shower-Curtain-Liner/dp/B00GM5U9YE/ref=sr_1_1?s=home-garden&ie=UTF8&qid=1423075164&sr=1-1&keywords=2.4+gauge+maytex+black+shower+curtain+liner

I assume that what I found in my doors was installed by the factory, so I was very happy to find something that looked like the stock material, although it may not be the best for this application.

For my Spider, the original installation involved an adhesive across the top couple of inches of the door rail.  About 2 inches of the liner was draped over the door rail (from the outside) and that was pressed onto the adhesive.  The remaining seal material was routed down inside the door where the window glass slides through.  Hence the majority of the seal/liner/curtain material was actually on the inside of the door, between the window glass and the interior sheet metal door skin.  The design would allow water to get inside of the door, and be directed to exit through the bottom drain holes in the door, but not contact the fiberboard door panels.

The seal/liner curtain only protected the rearward openings on the Spider.  The front interior door openings were sealed with black plastic caps that were sized to exactly fit their corresponding holes and they were also glued in place.

[Beatle]

I've found the best method is to use clear plastic sheeting.  Get the thicker stuff (I used the type used make spare parts bags through a bag sealer).  That way you can see what's behind the membrane without needing to remove it.

On the Alfa doors I've seen with the original adhesive in place, it's like a bead of putty with string down the middle.  Often dry and hard

I usually used windscreen mastic to reaffix the plastic sheet, but it is black and sticky and can get all over things if you aren't careful.

On Alfettas and I think 105s, the mastic was originally shaped to ensure any water hitting the sheet is directed to the holes punched in the door frame.  Once again, using clear plastic you actually see how you've done with the adhesive even after the sheet is stuck.  You need to ensure there are no spots where water can pool.  i.e. no U shaped areas without a hole at the very bottom.   The door frame on Alfettas has a groove pressed into it, but that groove is not necessarily the correct routing for a bead of adhesive, so don't be tempted to follow it religiously with your bead of sealant.