Saturday, 31 October 2015

Paint Surface Problems and Corrections: Part II N to W

Nitrocellulose lacquer or Enamel Paints
The older technology paints on classic vehicles are oil-based and requires the oils in the resin binder system to be replenished to keep them from becoming too brittle and cracking

Correction- check the paint with a PTG to see how much paint there is available before attempting repairs
·         Wash the paint surface and dry thoroughly
·         A detailer’s clay process will remove any surface contaminants 
·         Use a chemical paint cleaner to remove any oxidation (Klasse All-In-One)
·         Apply an oil rich product to stabilize the paints binder system (3M Imperial Hand Glaze) apply a thick coat and allow to dwell for 12-24 hours before polishing, repeat as necessary until surface has an ‘oily’ sheen.
·         Using Gloss It EVP Pad Prime on your pads will help maintain sufficient oil lubrication for the polish
·         You are now ready to commence the polishing process
I would suggest you use a wool pad for correction; this will reduce kinetic friction (heat) and not dry out the oils

Orange Peel 
Is paint film surface that has a dimpled appearance that paint takes on due to an equipment/operator caused defect? Like wrong paint-gun pressure and/or distance from panel, an operator not knowing how to set-up the equipment for that particular type of paint, or even a partly blocked paint-gun nozzle, improper pre-paint preparation and /or paint application, or uneven drying of the clear coat.
It should be eliminated after the final shooting of clear coat by the OEM wet sanding the paint film surface, and polishing with a mildly abrasive polish and a high-speed rotary polisher.
Note that some degree of orange peel can be found in most finishes, both OEM and repainted.

              Correction- check the paint with a PTG to see how much paint there is available before attempting repairs Clear coat that is too thin loses its ability to adhere effectively (delaminating) to the underlying paint layer and will flake off.
A vehicle with its original paint has a higher re-sale value than a repaint. Due to the above; something else to consider is a ‘do nothing’ option and learn to live with it.
It can be removed by wet-sanding but this entails a substantial reduction in clear coat thickness, which may eventually entail repainting

Reduction - the way light is reflected from a paint surface affects the vehicles appearance after it is detailed. Reflection of light is either Specular (mirror-like) or Diffused (retaining the energy, but losing the image) depending on the nature of the surface. It is also possible for reflection to occur from the surface of transparent media, such as water or glass.

A paint surface that has 'orange peel' diffuses the light reflection, a wax also shares this reflection trait in the so-called 'wet-look' (jetting)So by applying a Carnauba wax to a surface that has 'orange peel' you are not masking the effect, but disguising it by making the rest of the paint diffuse light reflection in the same way

Oil Deposits 
Usually from diesel fuel exhaust, clean with a chemical paint cleaner and then apply paint protection

Oxidation (Reduction)
                  Two stage paint system- (base, colour and clear coat) - a clear-coat finish does not oxidize in the true sense of the word (meaning that the pigments and resins mix together and the pigments are exposed to the sun's ultra-violet rays, which causes them to dry out or oxidize. The clear coat is applied to protect against this but the finish will become ‘dull’ by using harsh (abrasive) or if acidic car washing solutions as used in ‘touch less’ car washing systems, or from industrial airborne pollutants compromising the clear coat allowing the suns heat to dry out (oxidize) the paint.
The clear coat layer is extremely thin (1.5 – 2.0 Mils) it is not a solid coating and is to some extent porous, the top most layer of clear coat paint contains ultra violet (UV) protection. Oxygen interacts with substances in the paint layer (i.e. mica flakes as in metallic paints) and trigger the oxidation reaction. It's just that the amount of oxidation taking place is minimal in comparison to single stage paint.
     Clear-coat dulling has the appearance of oxidation, i.e. paint surface has little or no gloss and may exhibit a slightly ‘grey’ colour but can usually be rectified without the need to re-paint.
This can be brought about by abrasive washing which simply dulls the paint; touch less carwash washing, which uses an acid that dulls the clear-coat and / or simply from exposure to industrial fallout and UVR, etc.
• Wash the paint surface and dry thoroughly
• Clean the paint with chemical paint cleaner (Autoglym Paint Renovator or Klasse All-In-One) using an orange foam pad at speed #4, this may take 2-3 applications
• Apply a paint surface protection

      For highly oxidized paint try the following; this may help to eliminate some of the oxidation-
• Wash the paint surface and dry thoroughly
• Clean the paint with chemical paint cleaner (Autoglym Paint Renovator or Klasse All-In-One) using an orange foam pad at speed #4, this may take 2-3 or more applications
• Once the oxidation has been removed use a decontamination system (C.Quartz IronX)
• Apply an oil rich product to stabilize the paints binder system (3M Imperial Hand Glaze) apply a thick coat and allow to dwell time for 12-24 hours before buffing, repeat as necessary until surface has an ‘oily’ sheen.
• Remove residue with 1:10 solution of isopropyl alcohol and distilled water
Finally apply a coating (Opti-Coat™) a pre-polymer that cross links and forms a semi-permanent continuous film on the surfaces it is applied to similar to a single component isocyanate that forms a clear coating finish.

          Single stage paint systems (base and colour coat) – without a clear coat to provide protection, primarily a hostile environment will attack the paint surface causing microscopic gaps and valleys (micro fissures) and it becomes compromised both chemically; by industrial fallout (IFO) acid rain, brake /rail dust and etc., and by ultra violet (UV) heat radiation, which causes it to dry out and/or fail, further causing the clear coat to expand and often separate from the base coat, allowing environmental pollutants to penetrate.

Acids enter the breach formed in the clear coat and attack the resin binder system, which accelerates the degrading of the paint film surface, eventually leading to oxidation and/or failure. Oxidation can appear as a dull and somewhat hazy, or `chalky' appearance to the paint surface, a paint film surface that is adequately protected with wax or a sealant actually has a lower surface temperature than one that is not.

A dark colored vehicle parked in the sun can attain a surface temperature in excess of 200° F With both types of paint system the application of a Carnauba wax provides a sacrificial and easily renewable barrier against airborne contaminants, which means the wax is compromised not the paint system

Single stage is easier to correct than most clear coats, as a general rule use a more aggressive pad before moving up the scale in an abrasive polish. Start with a Lake County (LC) Orange (light) cutting foam pad with Optimum Polish or Menzerna Intensive Polish (IP) you may also want to try an LC yellow cutting foam pad.
If you need a more abrasive polish; use a high speed rotary and try Optimum Hyper or Menzerna  Power Gloss with a LC White polishing foam pad, if  the results are not satisfactory then step up by to  going to a LC Orange (light) cutting foam and then if needed a LC Yellow cutting foam pad.

Polishing Fresh Paint 
If it just came from a paint / body shop fresh paint shouldn’t need polishing. If it should, I would strongly advise against the use of heavily applied pressure and overtly abrasive products.

Automotive paint is classified as a semi-permeable membrane; that has both tensile strength and elongation (elasticity) allowing it to move with fluctuations in surface temperatures. Newly painted surfaces are full of out gassing solvents. Kinetic surface friction and applied downward pressure transfers its energy into heat / torque (force to rotate an object about an axis) which; causes the paint film paint to become thinner by elongation and the pad rotation to transmit shear stress (twist), which could result in the alteration of the paint films bond between its substrate, causing it to delaminate or tear? 

The heat makes the gasses expand (pV = nRT) the expanding gases go through a phase transition (change in density) and to relive this increased pressure they rupture the paint film surface and may cause small fissures (similar to solvent pop or pinholes)

Paint Runs or Waves 
Runs on the vertical surfaces, is the result of a clear coat that sets up to fast. The slower the clear dries the more it flows out, the slicker is looks, the faster it dries the less time it has to flow out. It could also be the result of  too much paint applied too quickly and gravity tends to pull it down (See also Orange Peel)
              Correction- it can also be removed (with limitations) by wet-sanding (colour sanding)
Paint Cracks
Acid rain, highly alkaline deposits, industrial fall or bird excrement will cause the clear coat to become opaque (cloudy) and / or etch (a small circular concave depression) another type of localized damage created by acidic substances are the results of water and high temperatures that will cause the polyurethane clear coat to expand, allowing the acid to breach the clear coat compromising the paints resin system, which is the binder that holds the clear together. The resultant cracks created will penetrate the clear coat, possibly down to the basecoat (colour). 

May be due to painting over ‘filler’ (Bondo) that has subsequently involved in a small hit
Correction- cracked paint will need to be sanded, feathered, primed and repainted. Most shops will apply clear coat to the entire panel. .
Paint delaminating
This is usually the result of the vehicle manufacturer's decision to produce vehicles with one of the following conditions;

•Insufficient clear coat film build
•Insufficient UV blockers in clear coat
•Surface primer was not applied over the e-coat (anti-corrosive primer)

The e-coat, (first layer of paint coating) is extremely susceptible to ultra violet rays, when ultra violet radiation (UVR) penetrates the clear coat and base coat; they are normally stopped by the surface primer.
E-coats oxidize (looks similar to chalk powder) very quickly when exposed to ultra violet radiation (UVR). Subsequently the base coat and clear coat no longer have a clean, firm surface to adhere to.
Over time the base coat / clear coat detaches from the e-coat, resulting in this condition, which cannot be corrected by polishing or compounding

             Correction- It requires repainting / refinishing by a body shop
Paint Photo degeneration
Why does ultra violet radiation have a more pronounced effect on red paint?
The sun gives off many different kinds of radiation. Most people are familiar with the visible light spectrum or sunlight, with colours ranging from violet to red, violet being in the centre and red a little to the left.

Ultra violet light has two components UV-B (light), which causes photo degeneration and infrared heat (IR) radiation.

Red paint when subjected to infrared radiation (IR), the most concentrated form of heat radiation, which causes the resin (paint binder) in a paint system to dry out (oxidation)
Any dark colour absorbs heat but the pigmentation in red paint fades quicker and its more noticeable because the colour fades to a lighter shade (light red or pink) whereas black fades to a lighter shade but it only noticeable when it’s in an advanced stage of oxidation.

Allied to this some red, black and white vehicle paints are single stage, that is they have no clear coat with its inherent ultra violet radiation protection

Rust blooms
Very small brown ‘pinholes’, they are usually caused by metallic brake dust that has penetrated the paint film surface and water / acid rain has produced rust.

         Correction- sand or compound with 1200 or finer grit paper to remove and then polish to restore gloss. Consider using a decontamination product C.Quartz IronX

Rust Spots
Very small brown ‘pinholes’ or ‘rock chips’, they are usually caused by road grit that has penetrated the paint film surface and moisture / acid rain has produced rust.

         Correction- sand or compound with 1200 or finer grit paper to remove, use a rust inhibitor product Rejex CorrosionX, use chip repair paint and then polish to restore gloss.

Paint Blending (Repairs)

Paint ages and fades due to ultra violet radiation exposure, which causes photo degradation (fading). This happens to both the colour and clear but some colour change more than others; matching paint colours is an art.  Combine the base colour coat with flakes and tints then add a few costs of clear, some tinted and some not.

The quality of the blend will be determined by several factors....
·         Prep work- sand beyond the area to be painted.
·         Paint normally and thin the paint at the edge of the blend.
·         Apply the clear over the repair, thin it and extend the spot then dust straight slow reducer over the dry edge to melt the edge into the surface scratches.
·         Allow the new clear to fully cure before you try to polish the edge to make the blend invisible.
·         After the application of the  last coat of over-reduced clear, immediately empty out the clear from the gun and pour in a little slow reducer and dust it lightly over the wet edge of your blend so that it helps the edge melt into your sanding scratches.  Don’t try to make the edge smooth by spraying this reducer too wet or you will cause the clear to puddle or run and then you will have bigger problems on your hands.
·         Use high quality materials because low-end products may not bond to the surface properly and may not get hard enough to polish without breaking back.
·         A good quality spray gun will also help because you want an even application of well atomized paint.
Dark colours are much more critical because you can see problems much more easily than with lighter colours

Paint Surface Staining

A paint film surface becomes stained when continually exposed to an outdoor environment and inclement weather. Dirt and pollution accumulate in the microscopic pores and surface imperfections of the paint film surface and causes it to become clouded and grey, which over time causes a staining effect that hides the true colour of the paint system.

Chemical or pre-war cleaners are a mildly abrasive (CAS = 1/10) liquid polish containing chemicals will remove surface contamination that either normal washing or using detailer’s clay alone will not remove. Light colored paint shows this staining more than dark colours; white being peculiarly vulnerable to staining

Removing paint staining build-up requires detailer’s clay to remove imbedded particles, a paint safe chemical cleaner (Klasse AIO) to clean road dirt and grime and a machine polish to clean the surface and replace the necessary oils. Once the surface has been ‘cleaned’ apply a polymer sealant and/or a wax for surface protection.
Removing tyre ‘sling’, exhaust carbon or petroleum gas stains from paintwork- use a d-Limonene based   (citrus) cleaner 3M Citrus Cleaner Adhesive Remover Spray, ValuGuard "N" New Car Prep or  paint cleaner (P21S Paintwork Cleaner or, Klasse All-In-One)

Paintless Dent Repair (PDR)

[Paintless dent repair (PDR), also known as "Paintless dent removal", is a collection of techniques for removing minor dents and dings from the body of a motor vehicle. A wide range of damage can be repaired using PDR; however, usually if there is paint damage, PDR may be unsuitable.

The most common practical use for PDR is the repair of hail damage, door dings, minor body creases, and minor bumper indentations. The techniques can also be applied to help prepare the damaged panel for paint. Such applications are referred to as "push to paint", or "push for paint".] 

Limiting factors for a successful repair using PDR include the flexibility of the paint, and the amount the metal has been stretched by the damage incurred. Hence, often extremely sharp dents and creases may not be repairable - at least not without painting afterwards.

PDR is much cheaper than traditional repair methods and is superior most of the time for many reasons.  It keeps the factory paint intact and for the most part, the car does not have to be disassembled in a major way that can also cause damage. It is also available in most major cities.  However, not all paint less dent repair companies are equal.  Like any job requiring a lot of skill there are some who are good, some that are bad and those who excel at this sort of work.  I would suggest working with someone recommended by a detail company as detail companies are used to having picky customers who require this sort of service who don't tolerate bad work.

The object of removing a dent is by pushing the metal from inside the panel. What you need to watch for is stretching; this occurs when they push too hard.
Also make sure they do not drill into any panel, as it will cause future rust. No Bondo or other fillers should be used. If a Paintless repair is carried out on a hood they must pay special attention to its reinforcement.

Glue and Pull- a good tech will use a combination of traditional tools as well as glue pulling tools to repair your car. a plastic tab with an access hole in the centre is glued on to the panel and then pulled with a slide hammer, any area's that are too high are then very carefully tapped down.
Drilling holes into the inner structure isn't allowed under any manufacture's and/or I-CAR guidelines and some insurance companies have a no drill policy; meaning that the technicians must not drill to gain access to repair the dents. It's a safety issue and therefore isn't a good idea.

Many of these inner panels have crush points that are intentionally designed to deflect energy away from the occupants, and even a small drilled hole can negatively affect this from happening. And it can also affect the OEM corrosion warranty; some rust protection application centres have been sued for drilling access holes to apply rust protection.

Paintless dent repair does have limitations, insofar as it cannot perform miracles.  It cannot take out huge dents or straighten bent frames. Some dents behind door intrusion beams or heavy unibody reinforcement areas where the reinforcement is bonded or welded to the outside skin are not possible to with this method. It must be possible to reach the backside of the dent.  Long handled and curved tools help, sometimes small holes need to be drilled but not every dent is accessible. I'd say 95% of dents can be reached without drilling though. 

Sometimes a repainted car with too thick or poorly prepped paint can have the paint crack while a repair is being made. Select an operative with experience as in most things you get what you pay for so check pest repairs and ask for references for past clients

It would take approx six months practice to become proficient and the tools are a large initial outlay (probably too large for an enthusiast detailer) But if you could find enough of this type of work it’s a great 'up-sell' to offer clients. I would suggest working with someone recommended by a detail company, as these companies are used to having picky customers who require this sort of service who don't tolerate bad work.

Online Access to Videos and Guides -

Removing Latex Paint Overspray–
1.       D-limonene based (citrus) based detergents (P21S Total Auto Wash) may help; be sure to allow plenty of dwell time.
2.       Solvents; dwell time is important, start mild with (3M™ Adhesive and Wax Remover or DuPont Prep Sol 3919
3.       Detailers clay (Auto magic’s Magic Clay) both red and blue grades
4.       Plastic razor blade to mechanically 'chip' the overspray
5.       A combination of the plastic blade or detailers clay and a solvent, be patient and work small areas when practical.
6.       The painted surfaces are frequently easier than anticipated, however the rubber and vinyl trim pieces may take more time / patience.

Removing Paint Overspray

Dampen but do not soak a terry cloth towel with lacquer thinner (do not use mineral spirits or turpentine) and then apply lacquer thinner to the paint overspray.

Wipe the paint overspray from the vehicle using a terry cloth and then dry the surface using clean dry 100% cotton towels. Do not leave lacquer thinner on the car's finish for longer than necessary as this may damage the clear coat. Use with caution on repainted vehicles

For extensive paint overspray removal
·         Wet-sand using 2000 grit finishing paper
·         Meguiar’s M105 and a SurBuf R Series pad
·         Meguiar’s M205 and a Lake Country (LC) Green foam pad
Paint overspray ‘spots’ – use detailer’s clay

Removing Oil

Soak the area with mineral spirits, then use a d-Limonene  based (citrus) safe solvent all purpose cleaner (P21S Total Auto Wash) once the mineral spirits have broken down the oil, the all purpose cleaner will create an emulsification of the oils, hose the area and then wash area with a car wash concentrate.

Removing dried -on rubber 
Use a safe solvent to remove burned on rubber; that does not contain any harmful components (heptanes or xylene or hydrocarbon aliphatic solvents; Autoglym Intensive Tar Remover, Stoner™ Tarminator, or Wurth Spray Solvent that simply emulsifies and dissolves the rubber, then use a plastic razor blade to remove any hard debris.

If this does not remove the rubber try a 3M Eraser wheel – this 4-inch diameter wheel is made from a soft white polymer, which looks and feels like rubber.  3M Stripe and Decal Remover

Removing (Stripping) Paint

Chemical paint stripper is the fastest way to remove paint, or at least to get the most material off quickly. It also allows you to more gently (less scratching) sand the remaining film off the bare metal. Stripper is easily washed off and neutralized (follow directions on container) and bare metal can be coated with metal prep (phosphoric acid).

Dry paint stripping (Plastic media) one of the processes involves blasting with a special plastic granule that was developed for use on military aircraft. This material will remove paint, glue, and light rust deposits and many under seals but will not generally remove body seam sealers without concerted effort and not at all in the case of the very latest products.

The advantages of using this plastic media over other materials are numerous. The material has a low mass, thus allowing low air pressure to be used in the blasting process. This minimizes the kinetic energy involved and consequently the amount of heat generated, which is the primary cause of damage or distortion to the material being stripped. This is especially important when working on light metals and alloys such as aluminium or on composites such as glass fibre or carbon laminates

Road Paint (Traffic Lane Paint)
Is a pigmented resin system, very high in solids with a colour aggregate and is more like an adhesive than paint; it contains silica (glass) micro beads that help reflect light, however they can cause scratches if you use mechanical removal.

       Correction / Removal - use 3M Adhesive Remover and detailer’s clay or a plastic razor blade.
            3M Eraser Wheel Detailer’s Clay
Wet-sand with 2000 - 2500 grit finishing paper and a Unigrit block.
For heavy accumulations or paint that has dried for several days on the vehicles paint surface, apply a liberal coating of Vaseline to the dried traffic paint and allow product to remain overnight and then pressure wash. This should remove most of the traffic paint. If not, repeat the procedure.

Road Paint Remover (wipes) – TOTL; Lay the smooth side of the wipe over the contamination to saturate the surface. Let it sit for about one minute to soften the paint. Use the textured side of a new wipe and rub vigorously. Use firm pressure and a lot of action. Particularly difficult cases may take a second application.
 Once you have removed the road paint, wash off the chemical with shampoo and a spot polish should bring back the original shine. (Do not use on paint that is less than 90 days old) The same technique can be used for old tar removal.

Car Brite Road Paint Remover -safely removes road paint, paint overspray, tree sap, tar, bug residue, urethanes, adhesives and rubberized undercoating from cured clear coat finishes.

Removing Road Salt from Paintwork
Corrosion [: Water has a low electrical conductivity, but this increases significantly with the dissolution of a small amount of ionic material such as sodium chloride.  Sodium chloride CI and water H2O produce oxides, which cause corrosion]
            ValuGard Decontamination System (B) alkaline neutralizer (pH 1.0) that is a blend of acids, which deep cleans painted surfaces to remove alkaline road salt / water solution deposits, pH 9.0 used for freezing point depression in a sprayed brine solution (often mixed with grit / sand for tyre adhesion) and safely dissolves salt particles bond with the paint so that they can be rinsed away. Apply to a clean and freshly rinsed surface. Allow product to dwell for 5-7 minutes, works well with detailer’s clay to remove contaminants.

All necessary safety precautions should be taken whilst using this product. Protect paint surface with a synthetic polymer sealant Collinite's Insulation Wax # 845 or Finish Kare FK1000P  (see also Undercarriage Care and Road Salt)

Removing Surface (dry) Dust
The best known brand (California Car Duster) it can be used to remove pollen or light dust without causing scratches hold at the end of the 21-inch handle and  applying very little surface pressure with the duster, dusting with long strokes in one direction only, the dust is collected by paraffin wax and held in the cotton fibres (the same way a micro fibre cloth works (but without the paraffin wax) Shake the duster after each pass to ensure any particles picked up will drop out rather than come to the surface while you’re using it.

It important to use the duster only for the removal of dry surface dust, if the vehicle has oily road film, road tar, damp pollen or dust, etc the vehicle surface should be washed (or use Optimum No Rinse (ONR) rinse less wash)
Dust build-up-with low humidity conditions friction on the paint surface will cause static electricity (this is exacerbated by the use of polyester (nylon) Micro fibre) resulting in dust attraction to the paint surface.
Rinsing the surface with water or applying a quick detailer (QD) or use the CCD as stated above to remove dust. When the duster is first purchased it should be wrapped in newspaper (48 hours) to remove any excess paraffin wax, the duster should not be washed, the dirtier it gets the better it works (I've been using mine now for almost five years without it being washed)

          Don't  use – on a wet surface (even condensation) as this will cause streaking, or soon after driving; as a hot surface will also cause streaking

Alternative product-Dust build-up-with low humidity conditions and friction on the paint surface will cause static electricity (this is exacerbated by the use of polyester (nylon) Micro fibre) resulting in dust attraction to the paint surface. Unlike most other car dusters which are wax covered cotton fibres, the GP Wool Duster is an all-wool Australian pelt. Rather than relying on surface tension to hold on to dust, our wool duster simply uses static charges, created by twirling the duster in your hands, to safely lift dust from the surface. Almost no surface pressure is necessary to make it 100% effective. GP Australian Wool Duster

Rubber Tyre Marks on Surface

Correction - Use a safe solvent to remove burned on rubber; that does not contain any harmful components (heptanes or xylene or hydrocarbon aliphatic solvents; Autoglym Intensive Tar Remover, Stoner™ Tarminator, or Simple Green® Aircraft & Precision Cleaner that simply emulsifies and dissolves the rubber, then use a plastic razor blade to remove debris.
If this does not remove the rubber try a 3M Eraser wheel – this 4-inch diameter wheel is made from a soft white polymer, which looks and feels like rubber.  3M Stripe and Decal Remover

Radiation Damage
Ultra violet Radiation is known to contribute to the chemical modification of exposed paint surfaces resulting in loss of gloss, colour change, chalking, flaking and eventually destruction of the clear coat paint film by oxidation.

Ultra violet protection is a sacrificial / renewable component; this is due to the UV protection layer (stabilizers) being degraded by exposure to the elements (sun, sand, road or sea salt, and etc) it is also water miscible, so it is imperative that you renew it and needs to be re-applied on a regular basis (dependent upon location climatic condition)

When radiation is absorbed, it starts to break (cleave) weak chemical bonds, which leads to photochemical degradation (bleaching, (fading), discoloration, chalking, brittleness and cracking) all indications of UV deterioration. The paint top surface loses its reflective ability and becomes ‘chalky’; this is a sign that the structural integrity (mechanical strength) of the paints matrix has become compromised.

The bond cleavages resulting from UV absorption cause the formation of “radicals.” Each free radical can trigger a chain of reactions (in the presence of air), leading to more bond cleavages and destruction. These oxidising chain reactions require no further UV exposure, just the presence of air

Once the air borne contaminates and pollution compromises the paint surface they accelerate the oxidation (reduction) or paint failure process, which leads to bleaching (fading), discoloration, chalking, brittleness and cracking - all indications of UV deterioration. Once a paint surface structural integrity is compromised like this it usually means the paint requires replacement (re-painting)

1.       UV radiation heat dries out the binder system causing structural failure; it will dry the resin in paint; leading to oxidation. A paint surface will often show cracking as the resin binder dries out the paint draws up on itself forming ‘crow’s feet’. It will also dry out the oils and plasticizers in vinyl and other materials and may lead to structural damage (this is especially relevant to open top convertibles)

2.       UV radiation light exposure leads to gloss and colour instability (photosynthesis or photo-oxidation) and surface fading stains. But before UV light can cause harm, it must first be absorbed. If it is not turned into heat or transferred to a nearby stabilizer molecule called a quencher, it breaks weak chemical bonds. This is the beginning of UV damage. Oxidation really amounts to a weakening of the resins that bind paint, which results in the micro-pores becoming exposed and a larger area of paint becomes oxidized. The paint top surface loses its reflective ability and becomes ‘chalky’; this is a sign that the structural integrity (mechanical strength) of the paints matrix has become compromised.

Some materials absorb UV radiation more readily than other materials. Materials that readily absorb (UV-B) radiation are quickly damaged...rubber, vinyl’s, gel coat fiberglass, and many other plastics.

'Soft’ (refinished) paint
 By lowering the OEM paint oven temperature and cycle time of the clear coat reduces (VOC), which creates a soft or sometimes sticky clear coat
This could also be due to not using the correct reducers / hardeners for the temperature the paint is to be sprayed and cured at, or the painter uses an incorrect mixture for a three part clear or there are contaminants on the paint surface or could be silicon contamination on the paint film or a strong solvent 'softening' or causing the paint to be sticky

       Correction detailing -
use a chemical paint cleaner (PrepSol or Hi-Temp Silicone Remover) to remove silicone. Use very soft foam (LC Black finishing pad) and a mildly aggressive polish as this type of ‘paint’ easily shows surface marring etc
Soft or Sticky clear coat
Some paints (isocyanate free paint formula, a clear coat with low heat and abrasion resistance, paint that has not sufficiently outgased or has insufficient hardeners, hence ‘soft’) this type of paint heats up very quickly causing the polish surface lubrication to dry out, which causes an increase in surface resistance, the pad feels like its dragging and can skip, as the polish abrasives stick to the paint

Correction - use a firm pad that has little surface resistance, a LC Purple Foamed Wool and Menzerna PO 203S or PO 106 FF polish with very light surface pressure.  You could also add more surface lubrication (Gloss- it Pad Prime) alternatively apply polish with an orbital polisher #4-5.

 Strikethrough (Paint burn)
 It should go without saying that you need proper lighting available when you’re polishing. Always work in good lighting conditions, and frequently check your work.  Without it you may polish through (breakthrough) paint surface or friction ‘burn’ the paint by polishing in one area for too long.
Basically when friction heat (kinetic force) has compromised the clear coat and exposed the base coat. Paint often looks a slightly lighter colour; it’s usually concentrated on a small area or ‘spot ‘You will also be able to see a non-glossy patch (base coat) where the clear has been removed with the edges of the remaining clear coat being visible .

Areas of risk- bumpers, as they don’t conduct heat like metal panels, edges an seams and the paint in these areas is generally thin (masking tape is good insurance) Applying pressure and holding the polisher stationary for too long will cause friction heat to be concentrated, especially with a foam pad. Clear coat provides both ultra violet (UV) radiation and the paint systems protection. Repair any breaches in the clear coat system otherwise you risk the paint delaminating, which will then require repainting

           Correction- replace the missing clear coat and ‘blend to match. Any areas that have been subjected to strike-through need to have more base coat sprayed to cover the problem, and then clear coat can be applied to provide UV protection.

The problem is that the new base will tend to lift the edge of the clear around the strike-through spot so you need to seal the gap in the clear coat before you apply more base coat. Seal the spot by using clear coat applied first and allow it to harden sand using finishing paper and then apply more base coat and finally clear coat.

It takes some experience to blend the clear coat and a novice painter can cause additional problems until gaining the experience needed to do it properly. Spot blending clear coat is not something an inexperienced painter should attempt.

Solvent Pop
[Blisters on the paint surface caused by trapped solvents in the topcoats or primer-surfacer, a situation which is further aggravated by force drying or uneven heating] DuPont website
Solvent pop can also be created if you heat the surface before the paint flashes a little. Don't put the new paint into the sun or use heat lamps before it's dry.

Correction- If damage is extensive and severe; paint must be removed down to undercoat or metal, depending on depth of blisters; then refinish. In less severe cases, sand until smooth, resurface and refinish] DuPont website

Chemically it’s an organic chemical containing sulfhydryl (a mixture of sulfur-containing chemicals such as methyl and butyl thiols traditionally called mercaptans), which are not water soluble.
To eliminate them and the odours they produce solubilise it (i.e. raise the pH from an acid to an alkaline) with an alkaline wash solution at which point it will become soluble and wash away.
Due to the chemical composition of the skunk spray, most household remedies are ineffective, with the exception of a peroxide formula or other remedies that break down the thiols.

Scratch Shield Clear Coat
Some paints (isocyanate free paint formula, a clear coat with low heat and abrasion resistance; this type of paint heats up very quickly causing the polish surface lubrication to dry out, which causes an increase in surface resistance, the pad feels like its dragging and can skip, as the polish abrasives stick to the paint
Correction - use a firmer pad that has lees surface resistance or an LC Purple Foamed Wool. Or try to add surface lubrication (Gloss- it Pad Prime) alternatively apply polish with an orbital polisher.
Transport (Microcrystalline) Wax

P21S Total Auto Wash or 3M Adhesive Remover both are safe solvents that are very effective for the removal of transport wax, a temporary protective transport Microcrystalline or co-polymer wax (See also Cosmoline)

Urethane Wave

This is something in addition to orange peel when layering thick clear coats for custom paint jobs and show cars. Painters will spray 3-4 coats of clear, block it down with 400-600 grit, and then spray a final flow coat. (See also Orange Peel)

Correction - this would require block sanding to flatten urethane wave.

Tire Dressing Overspray (Sling)
As you drive the tyres rotate and the inertia can cause tyre dressing to ‘sling’. Tyre manufacturers use carbon black to protect them against ultra violet radiation. Using a dimethyl solvent-based dressing (usually a clear greasy liquid) emulsifies it, if this contaminated dressing comes in contact with your paint and if it dries it will it will dye / cause a stain; it’s especially noticeable on light coloured and can irreparably stain the paint light colours and single stage paints.

Remedy- This can be caused by (a) applying the product to an improperly cleaned surface, to which it cannot adhere too. The preparation of the surface is the cause of this problem not the product (b) and / or an excess of product, after the dressing has penetrated remove any excess.

Removal - use a d-Limonene based (citrus) cleaner 3M Citrus Cleaner Adhesive Remover Spray or ValuGuard "N" New Car Prep or paint cleaner P21S Paintwork Cleaner or, Klasse All-In-One, failing this use an abrasive polish / pad.
Unfortunately, the only permanent remedy is to remove the stained paint down to e-coat and re-paint

Water ‘Spots’ 
[A water spot is an area of dried mineral deposits left on a surface after being allowed to air dry. Water quality, specifically the amount and type of minerals in the local water supply as measured by the total suspended solids or TSS test and other mineral levels such as sodium level, has a big effect on how severe water spots can be

If the surface can be rectified by chemical means then this is the answer; not abrasive polishing. Using the correct chemical cleaners will dissolve the contaminants rather than abrading the surface.  If water spots are not washed away using normal car wash they might be etched into the wax or surface. The next step would be to use a paint cleansing lotion or the cleaner wax indeed. Don’t use a pure carnauba product over the water spots as it has no ability to remove them and will seal them in. You can move to machine polishing as needed, but most the time newer water spots are removed with a chemical paint cleaner type product or distilled white vinegar

With all cleaning products (especially solvents) always test a small inconspicuous area first to ensure it won't discolour, stain or etch the surface, and ensure that the pH of the product is suitable for the material After the paint surface has been subjected to a chemical cleaning its protective layer (s) have been removed and the paint surface left without protection, so it is very important that a polymer and / or Carnauba wax protection be applied immediately

Water doesn’t leave marks or etch glass; it’s the minerals that it contains calcium (Ca) and magnesium (Mg) and reactivity (heat acting as a catalyst) the spots are actually traces of minerals left on the surface. Alternatively they can be caused by industrial pollution (i.e. acid rain, bird Ca2+ and Mg2+ excrement or industrial fallout)

Generally surface water-spots have no raised edges and are very shallow and so cannot be felt, they are very similar to micro-fine surface marring. They cannot be removed from the surface by washing but they can usually be removed with a slightly abrasive chemical paint cleaner

There are two categories of water mark (the so-called water spots)
1. Stage I Corrosion
[: defined as a surface with light to moderate corrosion damage to the paint surface]
2. Stage II Corrosion
[: definition when the dirt/corrosion deposits are no longer on the surface but have started to break down the molecular structure, leaving an etched or white haze on the surface( a concave circular mark ) after the stain has been removed, with moderate to serious paint damage]

Progressively using the least abrasive product first-
1. Use a paint surface cleaner (Z-PC Fusion Dual Action Paint Cleaner or Duragloss 501)
2. Try to dissolve the alkaline-based, surface/etched mineral water deposits try one or more of the following;
a) Use a 2:1 or stronger solution of distilled water/distilled white vinegar (Acetic acid)
b) Try a 2:1 solution of distilled water/Isopropyl Alcohol (adjust ratio as required)
c) Or equal parts distilled water/distilled white vinegar/Isopropyl alcohol.
3. Clean the effected surface with Klasse All-In-One or Zaino Z-PC Fusion Dual Action Paint Cleaner
4. Use detailing clay to remove any `hard' surface granules
5. Use a machine polish (Optimum Polish, Optimum Compound) and a cutting (LC White, Orange or Yellow) foam pad (speed # 4- 5.0) to level the paint surface
6. For Ceramiclear or other hard clear coats substitute Menzerna for machine polish; Super Intensive Polish / Nano Polish (105FF) or Final Finish Polish (106FA)
7. Use the least aggressive polish/foam pad first, if this doesn’t remove the problem step-up to a more aggressive polish / foam pad set-up
8. Menzerna Power Finish (PO203S) - (M) this is a one-step scratch remover polish is formulated for CeramiClear or other ‘Hard’ paints. It will remove 2500 grit, cut 3.0-gloss 3.5, is formulated as a quick way to polish out light flaws and amplify the paint’s gloss. Use a primed Orange (mid range, high density foam (60 PPI) medium abrasive cutting action LC CCS foam pad 1200 RPM
9. Wet-sand with 2000, 2500 or 3000 grit finishing paper
Due to the reactivity of the calcium (Ca) and magnesium (Mg) be cognizant that there are no products that offer complete protection; however either of these products will offer resistance to water marks, just remember; they are a sacrificial polymer waxes- Finish Kare FK 1000P Synthetic wax or Collinite 476S Super Doublecoat

Current Information
A little science is useful to understand both the How and Why of detailing and to be of real practical use, a subject like automotive detailing requires a great deal of research, and updating as new products become available. The advent of materials like detailing clay, micro fibre technologies and finely milled micro diminishing abrasives, suitable for ceramic nanotechnology paints are examples of why it’s so important to monitor the industries new products, chemical technologies and ideas that are constantly being introduced, as are the techniques for applying them, hence all of the in-depth articles will be up-dated and revised on a regular basis

Always be willing to learn; because the more you learn, the more you’ll realize what you don’t know. You should never stop learning, and your quest for information should be part of your everyday process. It is said that knowledge is power, with the caveat that it includes access to a reliable information sources. I would like to think that these articles become an asset to anyone who is new to detailing and to professional’s alike, as well as industry experts who seek to advance their knowledge.

I detailed my first vehicle at the age of fourteen (1958) forty plus years later I started to write detailing articles to share my experiences. For about fifteen years or so I started to contribute to various detailing forums answering questions posted by neophyte’s, enthusiasts and professionals alike. 

My mantra has always been Experience Unshared Knowledge Wasted.

I purchase all the products I use, so the endorsement is entirely personal and commercially unbiased, the product recommendation is based on "Does exactly what it says on the tin" and it suits my detailing goals. The products mentioned have been personally subjected to extensive laboratory (using state of the art instruments and methodologies in some of the world's most prestigious labs) as well as field testing, and using the methodology and tools cited, which may or may not be the same as those recommended by the manufacturer.

It has been my experience that they will perform the task more than adequately, hence the personal recommendation, as this testing is carried out without sponsorship I have no intention of publishing any test results. Using the methodology and tools cited, which may or may not be the same as those recommended by the manufacturer.

I hope these articles are informative. They are based on the current status of technical development as well as my experience with the products.

By having some understanding of the ‘What and ‘Why’ as well as the ‘How’ along with a little science to help you understand how the chemicals we use react, you can achieve the results you desire.

I would appreciate it if you would share these articles as it helps other detailers further their knowledge.

As always if you have questions, I’ll do my best to answer; bear in mind the only stupid questions is the one that was unasked. Questions and/ or constructive comments are always appreciated

Copyright © 2002 - 2015 TOGWT® (Established 1980) all rights reserved

No comments:

Post a Comment