Moving my chop out the garage the other day I brushed up against one of my other bikes with its cover on and managed to take some of the paint work of my new panniers (fig 1). A we bit peeved I needed a way to repair, and as I have a gem color shift paint (auto air colour water based paint) just touching in with an air brush wouldnít get the effect.
Now sometime a go when I had my firsts car (before I got into the pleasure of bikes) I had this sheet of paint that you cut to shape and use to touch in paintwork, and figured something similar might work in this case. I also recalled how the paint had pealed of the masking I had used when painting the bike and wished id kept some.
A quick hunt round the kitchen found some greaseproof paper. I sprayed it up as when doing the paintwork originally finishing with a bit of cellulose lacquer (fig 2). Its round as the only paper I could find in kitchen was for lining cake tins.
In my previous trade of traditional boat restorer and builder I would always suggest boat owners carrying some nail varnish to seal any chips or scratches you might pick up before water gets a chance to get in. This is also a good idea with bikes. If youíre lucky enough you may find a colour that matches but clear will do to seal any colour. Having sealed the scrape as soon as possible, you can then fix at your leisure.
The first trick of is to try it and get the paint to come away from the greaseproof paper cleanly. I find that tickling it at the edge with a sharp scalpel blade will usually get it started (fig 3). A corner is the best place to start (mine being round, I had to make my own). It doesnít matter if it comes away in bits as you are hopefully only going to need smallish bits to fill in the chips. Donít get more than you need immediately off the greaseproof paper to avoid contamination.
Once to have your bits of paint prepared a little bit larger than the chip you are trying to conceal, you have to master picking the paint chip up using the side of a sharp scalpel pressed into surface with it out harming the finish (fig 4).
Once you have the hang of this you may want to soften the edges of the chip with some fine sand paper, being careful not to make things worse. Then you need to rewet the nail varnish with some fresh and carefully maneuver the bits of paint into place and press home gently, the tackiness of the varnish should be enough for the scalpel blade to leave it behind.
This leaves it looking better (fig 5) and a final coat of nail varnish gently applied once the first layer of varnish has set and it vanishes completely (fig 6).
It might take a few goes to get it right so practice first, especially the positioning of the "paint chip". Fortunately if you muck up the job you can carefully remove before the nail varnish sets using acetone or nail varnish remover. Careful though, too much acetone or pressure can remove the original paint and do a lot more damage if not done gently.
The usual caveat applies, if youíre not sure what you doing donít do it !
This page added..18/05/13