Golf headliner fix how-to

GTi Golfs, those in all generations had something exceptional regarding trim while comparing with CL's, GL's, etc. You might find those bits in interior and exterior. I always liked that exclusive parts, but there is one exclusively annoying in some matter. I'm talking about black and soft GTi headliner material which felt off twice. At first occurence of this annoying thing I just sourced another used piece and did a replacement. But one year later the same thing happened which after I realised this is going to happen again and again. Moreover these are getting difficult to source since car is 30 years old and I'm speechless when talking new OE replace. It just don't exist.

Problem root cause is age, those years and humidity combined makes softening foam between headliner trim and forming foam to decay. Assuming all of that I came to conclusion I need to make some of home brew item, i.e. retrim it. 

First of all I did take apart old trim material from it

Here you can see remains of softening foam after an attempt to remove it. Actually there was loads of these friable lumps before. It's impossible to clean it completely. Besides that remains are still sticky but not enough to hold newly applied trim material.

Since it is required to use some glue for new trim material I need to remove an old glue layer completely. If not, I won't get any adhesion due to old softening foam scraps. Considering it I just peeled plastic layer with softening foam together. It did not come off easily and it took about 4 hours for me to do that. After that I could not feel my hands :D

But a result was pleasure to see

After sticky plastic layer removed form became very fragile. To make it more stiff I decided to put on layer of fiberglass which will be a repair work and old form will be preserved at the same time.