Sorting out old black paint
Right, I have got a black B5 A4 that needs some paintwork sorting but I think
I can hold out on a machine polish for the moment.
But I have some big scratches that I need to sort and a few big chips that are down to metal.
Can I first get a recomendation for a paint to use, and then a technique for blending it in.
Also what is a good cutting agent for old paint work I have tried sonus, which I read is worth like 6/10 in terms of cutting power but it only works a bit.
Paint-wise I would source proper touch up paint from Audi, in the form of a touch up stick. We always use the included dipper brush to transfer a small amount of paint onto a tile, before then using fine artists brushes to do any repair work. To fill stone chips and scratches, you need to firstly clean them out with a strong degreaser, then fill the defect until the fresh paint sits a little bit proud of the surrounding sound paint - it can take many attempts to get the fill height high enough (the height of the blobbed in paint drops as the solvents evaporate during the drying process). Once filled and dry, you then need to flat back the proud infill using wetsanding paper; 3000 grit is usually sufficient, but sometimes 2000 grit can be useful too. This will level off the repair, but leave a matt sanding haze. You then need to wash the panel again carefully, and finally polish out the haze using a compound and finally a finishing polish. Decent polishes for use on hard Audi paint include those by Menzerna, with Intensive Polish (compound) and Final Polish II (finishing polish) being the obvious choices for hand use. If the paint is very tired looking then a machine polish would likely work wonders; doing it all by hand is going to be very hard work!