Car Painting E-Book

Matthew Jones

• Herausgeber: Crowood
• Kategorie: Lebensstil
• Sprache: Englisch

Seitenzahl: 212

Veröffentlichungsjahr: 2015

Beschreibung

An essential guide to all aspects of car painting, for keen amateurs and professionals alike. With step-by-step instructions and illustrations throughout, Car Painting covers the entire process - from panel preparation to spraying and painting techniques - offering guidance and tips on painting your car to a professional standard. With a focus on safety throughout, the book also covers: selecting and understanding paint, including important legislation; materials and equipment, and building your own paint booth; preparing your car, including parts removal, sanding, chemical stripping and rust proofing; masking and priming; painting techniques - spraying, clear coats and drying; stripes and custom touches; polishing, reassembly and preservation and finally, troubleshooting. Superbly illustrated with 200 colour photographs.

Leseprobe

First published in 2015 byThe Crowood Press LtdRamsbury, MarlboroughWiltshire SN8 2HR

www.crowood.com

This e-book first published in 2015

© Matthew Jones and Ian Taylor 2015

All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from the publishers.

British Library Cataloguing-in-Publication DataA catalogue record for this book is available from the British Library.

ISBN 978 1 84797 948 3

DisclaimerSafety is of the utmost importance in every aspect of an automotive workshop. The practical procedures and the tools and equipment used in automotive workshops are potentially dangerous. Tools should used in strict accordance with the manufacturer’s recommended procedures and current health and safety regulations. The author and publisher cannot accept responsibility for any accident or injury caused by following the advice given in this book.

DEDICATION

I made a bet. I lost. Grace Melville, I cordially dedicate this book to you (but also to my father and George).

For my father, Ian Taylor.

CONTENTS

PREFACE

1 ALL ABOUT PAINT

2 GETTING STARTED

3 UNDRESSING YOUR CAR

4 DENT REPAIR AND RUST PROOFING

5 PAINTING TECHNIQUE

6 MASKING

7 PRIMERS

8 PAINTING

9 STRIPES AND OTHER CUSTOM TOUCHES

10 DISASTER RELIEF FOR THE AMATEUR PAINTER

11 BEYOND THE PAINT BOOTH

12 REASSEMBLY

13 KEEP IT PERFECT

INDEX

PREFACE

Today, automotive painters are in a very fortunate position. The products available to them have never been better, both in terms of the final finish and in terms of the preparation process. Every stage is catered for, and every problem will have a solution. This means that keen amateurs that want to try and do the job themselves will have the best possible chance of refinishing their vehicle to a professional standard than ever before.

However, using the products correctly and making a workspace suitable for the job require a lot of preparation and knowledge. This book will tell you what products you need, how to use them, where to use them and what to do when you encounter any problems. It covers the entire process – from discovering the best ways to remove old paint, to panel preparation and on to the spraying process, as well teaching you the ways to ensure your finished vehicle looks better for longer.

It will also tell you how to protect yourself from the process. Painting a vehicle will require you to deal with several extremely toxic chemicals. You will need to learn how to protect yourself from them, the appropriate safety gear to use and a rough guide to current legislation.

Undertaking this job will also involve some local research. You will need to discover how much of the toxic, flammable materials required to undertake the job are allowed to be stored on your premises, how they are stored, what ventilation is required, how you need to dispose of any toxic waste and if you are even allowed to do the job in the place you plan to do it. Your local authority will be able to tell you everything you need to know, but you must make sure you are on the right side of the law before you start work.

Once you have done your research, you can begin repainting your car so it looks like new again.

CHAPTER ONE

ALL ABOUT PAINT

This chapter answers the following questions:

What paint do I have on my car (water-based, polyurethane, enamel, cellulose or two-pack)?What products can I apply to my vehicle (without causing a damaging chemical reaction)?How do I select the right colour (implications of a full colour change, colours that hide the most sins, colours that are difficult to maintain)?How do I match paint (how to match colours, difficult colours to match, find out what your car’s original colour was)?How does it all work (paint chemistry basics)?Paint and the law – what do I need to know (EU legislation regarding volatile organic compounds or VOCs)?Are there any health and safety implications (handling paint, skincare, ventilation)?

Use a white cloth and lacquer thinners to wipe an inconspicuous are of your car’s paint to see what kind of paint you have.

Before you can begin to apply paint to your car, you need to start by discovering the chemistry behind the process. This should help inform your spraying technique. It is also essential to know what kind of paint you have on the vehicle as it is this that will determine the extent to which you strip your car. Then there’s the law – painting throws up problems that must be addressed and researched before you begin.

FIND OUT WHAT PAINT IS ON YOUR CAR

Knowing what sort of paint your car is finished in will inform how you use this book. Discovering its type is a pretty straightforward process, but it must be done before you begin any work or buy any paint or tools. All you need is a white cloth, some lacquer thinners, 800-grit (or finer) sandpaper and a clean, inconspicuous area of painted bodywork, like the inside of a boot lid. Now dab your cloth with the thinners and rub.

If colour comes off immediately or the paint begins to wrinkle, you have enamel paint.

If colour only comes off after a lot of rubbing, you have lacquer paint.

If nothing comes off, you have urethane paint.

To see if the finish includes a clear coat, lightly sand a different area. If the dust is white, you have clear coat; if it is the same colour as the car, you do not.

While there is a chance that your car might already have been repainted at some point in its life, it is also worth getting some historical perspective on the sort of finishes that were popular throughout history:

1940s: enamel and lacquer-based paint (quick to apply, requires little finishing after application).

1950s: nitrocellulose paint/lacquer (requires several coats, then a clear coat on top; fast drying, easily correctible and gives a deep, glossy finish).

1960s: urethane and polyurethane paint (quick to dry and apply, durable and easy to correct).

WHAT DOES THAT MEAN?

It’s a matter of compatibility. Assuming the surfaces are prepared properly and you spray in the correct conditions (more on that later), you can lay enamel over lacquer. However, if you apply lacquer onto enamel, the surface will almost always wrinkle and get damaged.

The problems are a matter of chemistry – the solvent base for lacquer is far too strong for the softer materials in enamel paint. But compatibility issues do not end there. Paint systems are much like car systems. In the same way that you cannot bolt a Mercedes’ cylinder head onto a BMW engine block, there is a good chance you cannot use a BASF thinner with, say, a U-Pol paint; even more so considering increasing health and safety regulations imposed on paint manufacturers. Developers might even change application hardware, like spray guns, and the method of application to meet the required standards, which is an increasing imposition as legislation tightens in Europe.

There is a mass of information about automotive paint and its chemical composition, and you may wish to read more about it, but this book focuses on learning how to apply the paint itself, so the following information is a very brief, very basic guide.

Automotive paint is made up of three basic ingredients:

Pigments (colour)

Binders (adherents)

Solvents (thinners)

It works like this:pigments and binders are solid substances, and solvents allow them to be turned into a liquid and sprayed onto your car. Lacquer paints have lacquer thinners, while enamels and urethanes have reducers; but all of them evaporate, leaving the layer of solid colour on your car.

VOLATILE ORGANIC COMPOUNDS (VOCS)

But along with overspray, it is the solvent evaporation component of the chemical process that causes the most environmental problems and health risks. In 2001, European legislators stepped in to ensure that any paint products that produced significant emissions of ‘volatile organic compounds’ were regulated. VOCs are defined as any organic compound with an initial boiling point less than, or equal to, 250ºC (480ºF) measured at a standard pressure of 101.3kPa.

In plain English, a VOC in the world of car painting is a solvent or paint particle that mixes with nitrous oxides and produces ozone. When paint particles or solvents rise into the atmosphere (caused by overspray, which is paint sprayed that does not adhere to the car, and evaporation, respectively), they contribute to air pollution. The European Parliament has stipulated that the VOC content of certain paints and solvents should be ‘reduced as much as is technically and economically feasible taking into account climatic conditions’.

Limiting VOC emissions has been the impetus for lots of technical innovation in paint and paint booth-related products. To meet the requirements, paint shops have fitted down-draft ventilation and special air-filtration systems to stop VOCs escaping. Also, a special high-volume low-pressure (HVLP) painting system has been developed that produces 64ft3 per minute of air warmed to 32ºC (90ºF) at 5lb/in2. It means less paint bounces off the car and into the atmosphere, and offers the advantage that you will need to use fewer materials in the process. An HVLP gun can transfer up to 80 per cent from the gun to the bodywork, while a traditional system transfers around 40 per cent, which is barely more than an aerosol can.

Paint itself has also been developed to fall in line with the restrictions, the most notable product being waterborne finishes. As the name suggests, this uses water to suspend the paint pigments and deliver them to the surface to be covered, not solvents. Nearly all waterborne paints use a basecoat colour covered by a clear coat and once it dries, the chemical process is effectively finished. But with traditional finishes, the solvent gases continue to work through the surface for up to six months – known as the ‘flash time’ – which can cause problems if the surface is blocked by anything like detailing and polishing waxes.

This colour chart illustrates the various hues available.

It sounds like an excellent solution – and in terms of environmental impact it is a vast improvement – but it is not without fault. Despite reduced VOC levels, waterborne paint has plenty of lethal chemicals in it, so you need a respirator on at all times. It is also slow to dry, expensive and requires special materials for you to apply it (there will be more on this later).

Luckily, most major paint manufacturers sell a low-VOC, solvent-based coating that meets all the legal requirements. Also, you can buy chemical additives for some solvent-based paints that alter it so that it complies with VOC content.

If you are determined to create a finish as original as possible, you will be pleased to learn that the European Parliament has also allowed member states to grant individual licences for limited sales of products that do not meet the VOC criteria. It stipulates that it must be ‘for the purposes of restoration and maintenance of buildings and vintage vehicles designated by competent authorities as being of particular historical and cultural value’. That generally means the materials will be expensive, but useable for the DIY enthusiast and useful if you want to complete a faithful restoration.

COLOUR SELECTION

The fastest way to get a steer on your car’s colour is to consult the Vehicle Identification Number (VIN) plate, which is a small tag located on your car. Its location varies from car to car, so it is best to consult a car club or enthusiast to advise you. Deciphering this, and discovering which section of the VIN code relates to paint code, depends on the manufacturer. In the absence of an expert, copy all the numbers and letters down, then take it to a paint shop to decode.

But be careful – someone may have changed the car’s colour during its lifetime. It is also possible that it has been incorrectly tagged at the factory, though unlikely. As a fail-safe, it is a good idea to tell the paint supplier the basic colour of your paintjob – red, blue, green, etc. – and they will be able to tell if you if it matches up to the code before it is mixed in bulk.

Unfortunately, the complications and scope for error do not end there. If you are painting a more modern classic, there may be several formulas that are quoted for any one colour. It is caused by the automated paint process at the factory – at the production line a batch of, say, twenty cars will be painted one colour, then machines will be cleaned and they will spray the next twenty cars in a different colour. Very slight contamination from other colours and cleaning agents can cause variations from the colour as it appears in the tin.

Black is one of the hardest colours to paint perfectly as it reflects everything.

This is not much of an issue if you plan to fully repaint your car, but if you are attempting a localized repair, it is important that it is matched as closely as possible. Sometimes the car’s position on the line – and subsequent variation in paint colour – is listed in the paint code in up to ten different variations; other times it is not at all. If not, find the prime colour and check at a paint shop to see if they have colour chips that show the variations, then match up accordingly.

If you have single-stage or two-stage paint, you also have the option of using a spectrometer – it is the size of a shoebox and has a port on one end that shines a light on the surface, takes a very sophisticated reading of each wavelength of light reflected off the object and works out what colour it is. It is an expensive piece of kit, it requires you to send off a sample section, like a petrol-filler flap, and you will not be able to use it on more complicated finishes like metallics, but it does give a very accurate reading.

CHOOSING A NEW COLOUR

If you are fully repainting your car, you have the option of choosing an entirely new colour. But undertaking a full colour change will greatly increase your workload – more of the car will have to be taken apart, such as the engine if the bay is finished in body colour, as well as the whole interior if there are any un-trimmed sections. Also, in the world of classic cars, values are profoundly affected by originality, and any deviation from it may have implications for your vehicle, regardless of the colour’s desirability. If you do change it over, you will also need to inform (in UK) the Driver and Vehicle Licensing Agency (DVLA). Also remember that some insurers may refuse you cover, and it may invalidate any policy you already have in place on your car or increase the annual premium. Speak to your policy provider beforehand to check.

Then there is the matter of difficulty: it is more difficult to achieve a flawless finish with certain flat colours. Black, for example, reflects everything, highlighting the most minor imperfections in the sheet metal. This is especially challenging if you need to make repairs to the panel; even more so if welding is involved, because every slight ripple – however small – will be painfully obvious.

Bolder finishes like metallics are also troublesome for the novice. While their manufacture has improved exponentially since their inception in the sixties, you have to ensure even application.

Pearl additives are also challenging for beginners. They give a flat colour an additional tint so, when viewed from different angles, the colour changes slightly. TVR famously painted the Sagaris with multistage flip pearl. The effect is created using oxide pigments to milaceous iron oxide (mica) or aluminium. These tiny specs can be painted on one side and left clear on the other. As well as the similar problem of even application, it is difficult to achieve an identical tint across the car, and it will be hard to fade in and repair afterwards.

Avoid metallic if it is your first time painting.

Because they tend to reflect less than most, colours such as silver and beige are ideal for the first-timer.

If this is the first time you’ve painted a car, you’re opting for a full colour-change and you want the finish to look as good as it possibly can, the colours that hide the most sins tend to reflect the least, but they don’t tend to be very popular. These are:

Grey

Beige

Silver

Gold.

CHAPTER TWO

GETTING STARTED

This chapter answers the following questions:

What kit do I need to paint my own car (all the materials, equipment and supporting products required for the job, beginning to end)?How do I build a spray booth (all the requirements for building somewhere suitable for paint finishing)?Do I need to repaint my whole car (localized paint work vs. full car)?Do I need to plan the job (how to write and order a comprehensive job sheet, and stick to it)?

There are literally thousands of different options of materials and products to choose from. Make sure you make the right decision for your workspace. And prepare to be surprised – even a humble garage can be transformed into a paint booth.

GETTING STARTED

As with any specialist job, even understanding the impenetrable language of the tools required is a bit of a challenge, and if you get the wrong kit it will seriously impede your progress, or the quality of the finished product. They can also be fiendishly expensive, and if you are only planning to paint one or two cars, it might be a more economically viable option to rent some of the larger equipment. However, some supporting products like the paint gun itself are worth splashing out on – even in the same product line, there are very slight variations that mean you have to ‘learn’ individual products’ idiosyncrasies. We will talk in more detail about guns in later chapters, but first you have to prepare your work space.

HOW TO TURN YOUR WORKSPACE INTO A PAINT BOOTH

Regardless of where you live or what resources fall to hand, you can paint your car yourself. But to make the best of the job there are a few rules of engagement.

First – space. You do not need much, but you do need some. Make sure you can manoeuvre your vehicle so there is at least three metres of room around every panel at all times: you will need to keep your paint gun at between fifteen and twenty centimetres from whatever you are painting at all times, and be able to move yourself up and down easily at all times with your elbow bent, so this is a good safe minimum.

Even small spaces can be transformed into a workable paint shop, but there are some minimal requirements.

What you do not remove will have to be carefully stored.

Second – surfaces. Dust and dirt particles are the enemy here, so dirt and gravel floors are out. You will also need a flat bench on which to mix your paint, and none of it can intrude on your painting area.

Third – ventilation. As long as you can leave the door through which you have brought your vehicle open, you should be fine.

Finally – power. You are going to need to run a fresh-air respirator compressor, air compressor, a large fan and lots of lights, so you must have good access to a mains plug.

If your place fits the bill, you can now start work on making it into a paint booth. Here is what you need to do to begin the transformation:

Deep-clean your workspace. This should not be a quick job – you will inevitably have stored things that have got dusty. Box them away and move them out for a day. Dust everywhere with the door open, sweep the floor, vacuum extensively, then scrub the walls and floor down with soapy water.

Now you have a clean garage. If you have not managed to bin most of your old belongings, arrange them as efficiently as possible around the walls or, ideally, stow boxes and storage crates in some roof space. If your storage containers contain anything likely to leak, like liquids, make sure that they are wrapped in plastic to ensure nothing drips down.

Before you roll your vehicle into your workspace, position your equipment as efficiently and logically as possible. So long as your power lines are long enough, you can put some of the bulky items that you will need to get hold of – like compressors – outside; that way you avoid tripping over them and it will liberate more indoor space.

You can never have too much lighting when you paint a car – you will need to have at least one large, bright light in each corner of your garage, preferably two at each end, two more on each side of the middle of your space and four overhead, spaced evenly across the roof area. It may be more cost-effective to rent a set of telescopic lighting rigs (or, if space is tight, some tasklights) than buy them. Remember that all lights should be fire-proof (paint is extremely flammable).

HEAT LAMPS

The ideal temperature to paint in is between 15 and 20ºC (60 and 68ºF). If your workspace is much colder, moisture will find its way into the paint. When the paint dries, moisture will remain beneath it, and bubble up causing microblistering. If your workspace is too warm, the paint will not be able to flow properly, as it will dry too quickly, which will give the finish an orange-peel effect.

Where weather conditions vary, you will need to maintain and stabilize the temperature with some form of heating. Avoid propane space heaters as they produce a naked flame and they have a fan component that will blow dust and other contaminants onto your freshly painted panel. If your garage is not centrally heated, use infrared heating lamps, as there is no naked flame. Prices range from around £130 for a small unit to £2,000 for a multi-lamp setup, but they are available to hire.

Heat lamps will help you to moderate the temperature in your workspace.

WHEN IT COMES TIME TO PAINT

If you have a driveway in front of your garage, make sure it is thoroughly wet before and during the time you are painting – this keeps dust ingress to a minimum.

If you paint inside, do not wet your floor down, just make sure it is very clean. If you put water in an enclosed area it will add humidity to the air, which could affect the way the paint adheres to your panel.

Regardless of how neat you are, you will get speckles of paint overspray everywhere. The best and most cost-effective solution is to line your workspace walls with clear plastic sheeting, which you can buy by the roll from DIY shops. Roll an edge of it around some long, thin strips of wood and drill them into the ceiling or beams next to your walls. Drape down the plastic and attach it to the floor with duct tape. You’ll need to line the ceiling, too, but make holes for hanging light fixtures and remove any precious shades – they will get covered in paint.

For the section of sheeting in front of the workspace’s entrance, you will need to weigh down the lower edge of your plastic and cut a hole for your ventilation fan. The former stops dust and debris floating in and disrupting your paintwork. Just in case your fan accidentally gets set from suck to blow, tape a lint-free cloth to the blade guard. Once you have set up your sheeting inside, you should not be able to see any daylight between the fan and plastic. If you can, seal it up with duct tape.

RESPIRATION

When you are preparing your car for paint, you will be exposed to several damaging chemicals, and you have to protect yourself from them. You should also make sure that whatever you buy is fit for purpose. Here is a guide to what is on offer. Because of the toxicity of paint and the supporting materials you will use, it is best to opt for products that offer more protection than you think you might need. These products may be more expensive, but think of them as an insurance policy.

An N95 disposable fibre respirator will not be enough for a full paint job.

N95 RESPIRATOR

This is a disposable type with a fibre cover that goes over your mouth. This, categorically, isn’t suitable for painting a car, but it will just about do for sanding work. If you are allergic to latex, make sure it says ‘hypoallergenic’.

HALF-FACE RESPIRATOR