Introduction: Cabriolet Roof Repair

Hi there!

It caused a lot of headaches to see how the 2008 Audi A3 Convertible, which had its rear window released with glue, could be repaired. I have received some offers about 100,000 HUF value (~ $ 330 USD) , however Gathering information about 30,000 HUF ($ 98 USD) frame can be the thing , which is not made a compromise on the raw materials used, the quality and procured the best quality in all required small band, only the special tool syndication I considered investing money to be a priority.

I repaired my convertible in September 2020, so it was 12 years of factory gluing which understandably hardened, lost its elasticity, and parted from the material or glass, producing soaking.

I gave it a chance to fix it, which was done as described here: if anyone can help with this document, I’m happy, or if you have any further questions , feel free to contact me by email. The process took about a morning and this document was done without claiming completeness, just a well-intentioned assistance .

Step 1: Parts:

I needed (I had many of these tools at home, I had to buy the chemicals): - multi-tool sander which made it much easier, although the surface can be sanded without it:

-STANLEY window cleaner

- wallpaper cutter

-vacuum bathroom handrail and some wood / aluminum slats + wedge such as door support (this will press the fabric onto the glass plate)

-Optionally , on ebay aliexpress and similar sites, the vacuum adhesive disc can be replaced with the special tool, but since the price of 6 pieces in a set with a little glue was $ 100, I needed about 30 pieces, so I didn't buy this.

-plastic adhesive tape -Squeeze gun for glue cartridge: and most importantly: Sikatact go4it sikaflex polyurethane windscreen adhesive ( it is important that the roof should not be glued to the glass with any silicone-based adhesive, only with a polyurethane-based adhesive, preferably UV-resistant) Sika primer 215 sika primer 207 Sika activator 100 and associated brush.

Step 2: Before


Step 3:

The first step is to scrape back the black primer from the glass until the clear glass is completely cleaned.

Step 4:

In the second step, the adhesive residue must be removed from the fabric, also with a blade and abrasive. To do this, it is advisable to open the roof slightly to about 5 cm, which will loosen the tarpaulin. This must be closed before vacuum fixing, because if a loose tarpaulin is glued open, it will tighten on the roof structure and the glass when it is closed and tear the glue off the glass.

Step 5:

In the third step, we mask the glass on the part where we do not want the black primer to flow. This should be done with plastic tape, not paper because it flows under the paper.

Step 6:

In the fourth step, we prepare the fixation. Here again,

I note that the special tool that would be a fastener is worth it to anyone who deals with it. I had to glue the rear window of the car almost completely around because it was separated from the fabric everywhere. I marked in green what was still there, in red what was no longer. As a result, I should have bought a lot of fasteners, as much as I can use a roof with a canvas and a motor.

Next to it I had to fasten it on a long stretch and on 4 different sides of the glass. Anyone who has only the glue released at the bottom or top, i.e. on one side, can solve it much more culturally , with fewer fasteners. I needed it so much. Each convertible case is different, it lets go elsewhere, it has to be re-glued in different lengths, and with these raw materials the mounting can be changed very modularly , it can be put together like a lego toy tailored to our own case.

Fasten the entire lid as if it were already glued, then draw a circle around the location of the pads on the glass with an alcoholic felt cell (with an alcohol wipe that can be wiped off at the end), number the slats, photograph the setting and take everything back. This is necessary because once it is lubricated with glue, it is extremely difficult to handle, it is almost impossible to experience how we can completely squeeze the fabric around the glass for the duration of drying.

Step 7:

In the fifth step, clean the surfaces separately
from the glass and the strip of canvas roof to be glued with Sika Aktivator 100 (orange). This will break down even the remaining glue a bit and make it stick to the newly applied layer.

It is important to apply it in a thin layer, just slightly wipe it!

We are waiting for half an hour of curing time. It is
advisable to place a support between the glass and the canvas so that they do not stick to each other but keep a distance between them.

Sixth step wipe with Sika Primer 215 tissue thin and Sika Primer 207 or 206 glass (this latter black)

Let it dry for half an hour !

Step 8:

In the sixth step, squeeze out the area with glue and then fix it as noted above. Be careful not to leave a gap of 1-2 mm that is filled with glue, do not squeeze the glue completely out of the canvas and glass.

Step 9: Final

After about 5 hours of drying, the fixation can be removed. After
24 hours, you can peel off the masking tape or use a wallpaper cutter to cut off the spilled glue from the glass and scrape off any excess material from it.

The result after that: