The last couple of days I decided to do some more extensive research into wear on fabric roofs and the causes and, hopefully, any wonder cures. My research was not limited to Audi or indeed just cars!
Some of us have observed darker lines on our roofs usually where the roof folds up. The general consensus of opinion is that this is caused by pressure applied to the fabric when it is folded and is due to being damp and dusty. When stored the roof will have some movement which causes the dust in the damp roof to act as a slight abrasive causing the lines. The general feeling I got from the research is that, for untreated fabric roofs, this is merely a side affect of ownership!
None of my research though mention scuffing of the fabric itself in terms of a roof, but there were mentions that rubbing of fabric on fabric would, overtime, cause the fibres to be damaged. No shocking revelations there then.
So what is to be done. For the prevention of lines the recurring method that cropped up was vacuuming the roof. Ideally with a powerful hand held cleaner with a soft brush attachment. This should be done weekly during the “topless” months to ensure that there is as little as possible dust in the fibres of the roof which will cause the lines to appear.
One product that cropped up a lot on numerous forums was a fabric and vinyl cleaning and protection kit by the name of 303 Convertible Top Cleaner and 303 High Tech Fabric Guard. This seems to have some applied renewing properties. It repels water and dust.
Both of these come in spray bottles, however everyone suggests that you pour the cleaner into a clean bucket and use a sponge to apply to the roof and then a brush to work it in. The Fabric Guard is a bitch to remove from glass and paint apparently so again pour it into a pot and paint it on with a brush. The websites selling the stuff claim it will protect the roof for up to three years, however most people seem to reapply it once a year.
While everyone raves about the 303 products there is a down side from what I can see. The Fabric Guard must be applied to a totally dry and clean roof. The Cleaner requires a wet roof, apply the cleaner and work in with a brush or non abrasive sponge, then rinse off. You would then need to allow the roof to dry out, preferably in hot sunshine and on a non-windy day (so it does not get dusty again). Once applied the Fabric Guard needs to curer for 24 hours (again it must be kept dry). Okay if you have a large garage or live somewhere warm, but it may be a bit of a struggle in the UK!
The Cleaner seems to cost around 10GBP for 32oz bottle. The Guard around 15GBP 16oz bottle (note it was mentioned in one review it was not enough to do an A4 cabriolet roof so by association it may not be enough to do an A5 roof). It's a little on the expensive side too.
My regular supplier of my car cleaning stuff is out of stock of the Fabric Guard, and it's pointless doing this time of year in any case. So next spring I am going to switch to this stuff (from Autoglym Cabriolet Roof cleaning kit) and see how it performs.
