Styling Small dent. help needed

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Styling Small dent. help needed

Trav 1.1uno

LØÑG LÎVË THË ÜñØ
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Jul 5, 2005
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95
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Near Glasgow, Scotland
hey guys howz it goin. just a small thing, on the panel at front passenger side wheel, its a small dent but the paintworks done in and its starting to rust a little, i just want 2 tidy it up a wee bit, nothing major, was thinkin of rubbin it down and puttin black hamerrite over it, the cars black and i done that with one of the arches already. anyone any other ideas? and im dead bored just not cause i dnt no what 2 do style wise. again any suggestions?
 
In the short term, your Hammerite idea will certainly preserve the metalwork and make it less noticeable. But of course you do want to fix it properly, don't you? ;)

No-one replied to your message, so I felt sorry for you. Now I feel sorry for how long it's going to take to read my post!

Use 80 grit sandpaper to remove the paint and rust, wet (prevents clogging). Dry the area throughly before you fill - try not to fill beyond the sanded area. Don't be afraid to mix up small quantities and apply the filler in two or even three goes, it makes less sanding work for yourself the more accurately you can apply the filler. Sand the filler dry with 80 grit on a sanding block (don't be tempted to use your fingers unless the panel is a curved shape, which it seldom is on an Uno :)), then 120, then 240.

Apply a coat of primer, preferably a thin coat so that it dries fast. Re-fill any imperfections, then wet-sand with 240 and 400 grit. You should really be getting somewhere by this point - the surface should be smooth to the touch, and blended smoothly with the surrounding paint (the repair area will have 'grown' to a huge area but this is OK.)

If going for the ultimate job, you would apply a very thin coat of a quick-drying aerosol paint at this stage, and then sand this down. This is called a 'guide coat' because it shows you any bumps/holes that need further work. In any case, while wet-sanding you will be able to see any areas of orange peel that need smoothing off.

I try to never wet-sand filler, since the talc in filler absorbs water, and water held against the bare metal is never a good idea... It would be nice not to wet-sand the primer either. But practically-speaking, you get a much better result wet-sanding because the sandpaper doesn't clog. Also, the water puts a gloss on the surface, so that you can see any remaining dents or steps at the edges of the filler.

This might all sound like lots of work, but realistically you can get all this done in less than a day. But I recommend leaving it for a few days before the wet sanding, just to ensure the primer is completely hardened before you apply a few thin coats of topcoat paint, e.g. from a colour-matched aerosol. Allow about ten minutes between coats - so, half an hour should do it.

Working with aerosols, particularly primer aerosols, does present one risk compared with spraying commercially-available paint with a spraygun. The aerosol paint is thinned more with solvents, so that it can be applied reasonably smoothly. As these solvents evaporate, the paint dries - but it also shrinks. You have to be on your guard for this, because holes, scratches etc. will become visible. It's important to sand these out after the primer has fully dried, which takes a couple of days.

Also, you will need several coats of primer because the sanding will tend to go straight through. It's better to use several thin coats, because a single thick coat will usually run or sag, and it takes a lot longer to dry.

Applying the topcoat is perhaps the least arduous and least important part! All the work, and the mark of a good quality job, is in the preparation. In particular, make sure you have a progression of sandpaper grades - the grit number should be double the previous number used. Don't be tempted to skimp on this, otherwise the coarse sanding scratches will show through later in the topcoat. Also, don't be tempted to use spray putty/thick primer to fill the sanding scratches - it WILL shrink and show those scratches again...

You might wonder about using a power sander of some sort. Generally these are not worth the trouble - it's hard to keep a vibrating tool flat on the surface, and there will probably be repeating patterns of scratches.

You might also wonder about starting off with fine sandpaper instead of coarse, to avoid the scratches that I keep going on about. There are two problems; fine sandpaper tends to follow the contours that you are trying to flatten, so the filler will stand out a mile because it will be the bumpy part in an otherwise flat panel. The other problem is that fine sandpaper removes very little material, so the job would take ages longer than necessary. No point prolonging what is already a couple of hours' work...

You will probably want to give the topcoat a fine sand (1500-grit) and a polish with cutting compound, about a month after painting. You will be amazed at how well the new paint will blend with the old once you have done this.

Sorry if I've made this sound more difficult than it really is - I just want to help you get the best result, one that is just as good as a professional spraying shop can deliver given their rushed work schedules and high overheads.

Also, think of it this way. One day you will have a more expensive car but there will still always be those minor accidents (usually involving objects that strike while the car is stationary) which are usually not worth paying to be fixed. It would be a good idea to practice on the Uno, rather than risk messing up on that future project...

Thanks!
-Alex
 
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