A guide to DIY & Body Sprays Part-2

Use etch primer if you have gone through to the metal, and start off as localised as possible

For complete panels though, you will ideally need a gun because an aerosol's fan is so narrow

Be patient and build up coats of colour slowly with aerosols to avoid getting runs.

It’s not exactly childs’ play to rub a car down but straightforward enough if you have time and tools. A sander is essential yet cheap

Fibreglass panels are very vulnerable on their edges, as the stuff is strong but brittle. If you do find any tiny nicks, build the profile back up with stopper otherwise the damaged area is liable to flake, and take your new paint finish with it!

When preparing plastics or fibreglass, never use coarse abrasives as they will simply scratch the surface. If the item is in good shape, use only red or grey Scotchbrite pads. If there is some surface damage, then don't go any coarser than 320 grit to rub it away

Remember that the air for a spraygun will blow lightweight panels around, so don’t just hang them from a single wire. Instead, if you secure the panel at several points, it will not blow to and fro, causing the distance from the gun to fluctuate and so making the finish uneven

On complicated shapes, it is important too to keep the wrist action natural. So, for example, you will probably find it easiest to do the inside curve of the uprights in two stages, each one allowing your hand to curl inwards which is its natural inclination

Spray the edges first, then the main surfaces. At some point the two will meet and you will get two wet edges. This is the ideal breeding ground for runs, so pull the gun away as you approach the end of each pass to give a lighter coat where the paint is already wet

If the damage is substantial, then you will need to use a fibreglass filler to repair it, especially if the panel is cracked: the strands in the filler will help to restore its strength. Use metal tape on the back of the panel to give a shape to work to, then put the fibreglass filler on from the outside

Priming doesn’t have to be pretty and brushing it on is cleaner and thicker than a spray job. Rub down well though

If body is in fair order then this is really all you may need to make it acceptable for a respray

Probably the best way to save decent money on a professional respray is to strip and refit the car yourself

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Simon Goldsworthy continues his look at the paint jobs you can easily do at home, plus how get the best possible finish in less-thanideal conditions!

Last month we looked at using aerosols, and at the fine results you could achieve with them on localised repairs and painting small items of plastic trim. But we also mentioned that there were limitations to how big an area you can cover with such an inflexible spray fan.To illustrate this point, the stonechip in our pictures is perfect. Trying to blend in very localised repairs is only really viable if you can keep within a hand span of a panel’s edge. In this respect, you can use a swage line as a panel edge but our stonechip was on a large and flat panel that was highly visible. On something like this, you can blend in colour using an aerosol, but would struggle if you had to clearcoat such a large area using a plastic nozzle. Quite apart from the cost, you can’t vary any of an aerosol’s basic parameters (fan size, air pressure, mixture etc) so there is more chance of getting splutter or dry spray when attempting to cover such a large area and the end result would inevitably be stripy. For this, you will need either one of the electric sprayguns we looked at last issue, or a conventional setupwith a compressor and a gun for the final coats. Start off by using 600grit paper to take the damaged area back to metal, and then follow up with 240 and 120 grit paper as necessary to get the rust out of the chip. This particular ding turned out to be very shallow, so we could get away with just using a can of special high-build primer to bring them up to level. But because the damage had gone through to the metal, we first had to blow on a little etch primer to the damaged area.

Got the runs?

As we mentioned last month, when spraying with aerosols it is essential that you remain patient to avoid runs – the first coat will look like little more than a guide coat, the outline of the primer will still be visible through the second, while the third will only just start to obscure it. At this point, you can try blending the repair into the surrounding paint, but this will be hard to do invisibly on such a large, flat panel. You could try using a product called fade-out thinner (basically pure thinner) to melt the outer edges of the new clearcoat and blend it into the existing finish. Fade-out thinners don’t melt the original factory lacquer, just the stuff that you have freshly applied. Ultimately this kind of repair is not as durable as a full re-paint up to the panel edges as the blended edge will get polished away in time to leave a visible ring, but is more common where a fast turnaround on a sales car is needed. For most classics, you would be better off using a conventional gun for the final layer and painting up to the panel edges.

Off the car

Moving away from aerosols now, we turn to some more isolated repairs on components that can be painted off the car. Typical subjects for this kind of repair are mirror backs, plastic bumpers and trim pieces, and the photos show fiberglass extensions for the rear spoiler from a Toyota Celica and a set of wheelarch extensions for an Autobianchi A112. Fibreglass doesn’t have the same adhesion problems as plastics and can be treated as a normal panel when painting – it is no different to many body fillers and paint will stick to these without the need for any additives. Flexible items like the wheelarch extensions will need a plasticiser added to the paint to cope with flexing, but not rigid items such as the spoiler extensions. Both items are probably at the limit of how big an area you can do with aerosols, and if you already have a small compressor in the garage, the point where you should start thinking about buying a proper gun or electric sprayer. Do remember if you do go down this route that you are not obliged to use every drop of paint that you have mixed for the gun. In many ways, you want to have some extra to throw away because you don’t want to run out and get a dry area while you are mixing up some more as this will affect the finish. This is particularly true of metallic paints, as the danger of getting slight variations from one mix to the next is greater than with solid colours. Just remember that you will waste an awful lot more of both time and materials if you have to refinish an area because of runs, so use what you need and stop when the job is done.

Joint effort

Finally, a lot of people ask what a reasonable sum is to pay a professional for a full respray, and whether you can still get a budget job done for just a few hundred quid. Unfortunately the answer is rather unhelpful in that you tend to get what you pay for. But if you consider that good quality paint for a full bare metal respray can cost £700 or more, it is clear that even just paying a pro to put it on sees a starting price of at least a grand. Add bodywork repairs and this will double or treble and we’ve heard of five grand resprays. And however well the paint is applied, it will always look rubbish if the preparation is poor. This leads on to the next most common question: Can I save money by doing the preparation myself? You may do, although any decent sprayer with a reputation will want to make sure the preparation is up to scratch before reaching for the gun so you may not save as much as you hope. On a more positive note, you may be able to make big savings by stripping the car and fitting it back up yourself. Do remember though, that you may then have to add transportation costs to and from the sprayer if the car is no longer a runner.

Two toning

Perhaps your classic looks a bit jaded but doesn’t really require a full respray what’s the solution? Simple – two tone it! This was a popular option right up to the late 1960s on new cars and it can transform a car at a fraction of the cost and effort of a full respray. Take a look at the pics here for some ideas but keep it nice and co-ordinated though… Remember what they say about wearing brown shoes with a blue suit!

Sweeping statement

Ah yes brush painting… just how worthwhile is it? Well it depends upon the car concerned and its value plus remember that before mass production took hold, many oldies were coachpainted. It has to be said though that splashing a can of Dulux gloss on a Ferrari will devalue it somewhat but similarly smartening up a decrepit old Ford may not do it any harm (as we did on an old Granada bought for £20 a few years back!). As with all paint jobs, the secret is in the preparation and you need to treat a £50 splash over just the same as a big buck respray – and that includes top materials and quality paint brushes. Sadly many don’t and because it’s such a boring tedious job, it’s easy to lose interest. The trick is to attack a panel at a time and spread the work over a period, if you can. We’ve seen some surprisingly good results too and another crafty ploy is to use brush painting as a two toning exercise so the eye doesn’t instantly draw towards the brushwork finish like a magnet. There are numerous specialist coach paints around and Halfords now markets Re Paint, which has been around for over 30 years. Costing less than a tenner a tin it’s available in numerous colours including Land Rover Green. It works well although remember that. in line with many other enamel paints. it can’t be polished or cut back.