Saturday, 16 December 2017

Pencil hardness

Pencil Hardness Tester

 Hardness: [In materials science, hardness is the characteristic of a solid material expressing its resistance to permanent deformation. There are three principal operational definitions of hardness: Scratch hardness, Indentation hardness, Rebound or dynamic hardness]
 Modern clear coat urethane even though they are harder than lacquer paints, they still scratch more easily. And because they tend to be harder it's more difficult and time consumer to remove swirls and scratches. This is the main reason to take vendor claims of ‘provides 9H hardness ‘for what it is – totally irrelevant.  
 How can a dense (hard) clear coat be so easily scratched? Force acts through a body that has a surface area; if the surface area is really small while maintaining an equal force, the pressure becomes astronomical and the object under pressure capable of penetrating the surface of an otherwise tough material. (Newton's third law of motion)
 Hardness is dependent on ductility, elasticity, plasticity, strain, strength, toughness and viscosity; suffice to say it is extremely important that paint hardness is properly taken into account when polishing, because if it is not then inappropriate polishing products and pads may be selected that either remove too much paint or turn out to be completely ineffective
 Hard and soft are relative terms; you can   forces are the subject of Newton's third law of motion; the law of reciprocal actions [: to every action there is an equal and opposite reaction]
 It is important to note that manufacturer-approved paint suppliers vary by country as each country (and even province/state) has their own environmental laws they must adhere to.
 Paint is graded by its hardness or density by a Durometer; one of several measures of the hardness of a material. Durometer, like many other hardness tests, measures the depth of an indentation in the material created by a given force. Clear coats can be made with harder or softer durometer and that will also determine its scratch resistance.
 Pencil hardness test is one of many non-Scientific tests that are done to evaluate a coating's performance. Other tests are abrasion, reverse impact resistance, direct impact resistance, cross-hatch adhesion, oxidation, gloss retention, UV resistance, yellowing, blistering, drying times, chemical/solvent resistance (using both the rubbing and spot/time tests), salt spray resistance, humidity resistance, acid and caustic resistance, the VOC and HAP contents, and so on.(See also American Society for Testing and Materials (ASTM) publications)
 Pencil Hardness Tester
The pencil hardness test, also referred to as the Wolff-Wilborn test, uses the varying hardness values of graphite pencils to evaluate a coating’s hardness.
The Elcometer 501 Pencil Hardness Tester has been designed to ensure that the cylindrical pencil lead is maintained at a constant angle of 45° and exerts a force of 7.5N (1.68lbF).
 The pencil lead, prepared beforehand using the special sharpener and abrasive paper, is inserted into the Elcometer 501 hardness tester and pushed over the smooth, flat coated surface.
 The lowest hardness value of the pencil which marks the coating determines the coating’s hardness rating.
 After doing some testing on various coatings for their 'pencil hardness'. The hardest is a 9H, followed by 8H, 7H, 6H, 5H, 4H, 3H, 2H, and H. F is the middle of the hardness scale; then comes HB, B, 2B, 3B, 4B, 5B, 6B, 7B, 8B, and 9B, which is the softest.
 Does paint density (hardness) affect its scratch resistance? - many coating products claim an obtained surface (Pencil) hardness of 9H but this has little if anything to do with scratch resistance. Scratch resistance can be related to higher cross-link density and elasticity of the coating network as well as the surface’s friction resistance.

Priming / Seasoning Pads


If you were to apply polish to a body panel, and then place a pad on the surface and turn the machine on, it would be very difficult to control and will produce hazing. This is due to most of the pad being "dry". Polishes and compounds appear to work better when the foam pad is ‘primed’ some things to note about pad priming: the cutting ability is increased, a better finish is obtained, it reduces any product ‘flashing’ problems, it produces a more even finish and the polishing machine is less likely to hop. Use a very slightly distilled water dampened pad, not too wet (otherwise the polish will clump); then spread the polish / compound over the pad evenly

Priming / Seasoning Pads

Don’t use a quick detailer or a pad conditioner as they are usually formulated with silicones, oils, waxes, polymers, gloss enhancers, which will negatively affect the polish lubrication (exception Meguiar’s Final Inspection Spray, diluted 1:1 distilled water) spraying water while polishing can cause the foam pads abrasives to aquaplane, as water for all intents and purposes is incompressible, so that the pad and the abrasive don’t have actual surface contact, thereby negatively impacting the polishing process. Spread the polish / compound over the pad evenly and ensure it is absorbed into the foam, then spread that polish onto the pad by hand until it becomes 80% saturated.

By ensuring the pad doesn’t become saturated with polish it allows the in-built cushioning effect and the pads designed foam qualities; i.e. density (or rebound), compression (‘hardness or stiffness) and without altering its in-built air-flow, which will decrease its heat dissipating abilities, causing it to transfer more kinetic friction heat to the surface

To apply to the paint surface; lightly raise the back of the machine so you are working with the top 1/3 of the pad. After polishing for a minute or two the pad will become more evenly saturated with product and actually become softer from friction induced heat build-up (seasoned). At this point, you can safely transition from a tilted up to a flat polishing position. Every time you put a fresh pad on your machine (and this should be done often) you should prime and then season it for a minute or two before "flat" polishing.

Once the pad has been seasoned (pad should be 80% saturated with product being used to compound / polish) you can reduce the amount of polish / compound applied to the pad for subsequent passes; dependent upon what you're trying to accomplish. If you use too much polish or compound the oils will cause the surface to become over lubricated, which will negatively impact the abrasive abilities

Some advantages to pad priming:
Increased cutting ability
Better surface finish
Eliminates carrier system (solvent) flashing problems
Surface is more evenly polished and polisher is easier to control

When you prime entire pad, by spreading the abrasives uniformly and by keeping the pad flat thus ensuring constant paint / polish contact it becomes similar to a piece of wet-sanding finishing paper, the oils in the polish provide the lubrication (like the water does in wet-sanding)

Polish Lubrication

Gloss It EVP Pad Prime is high-grade lubricating oil that greatly extends machine polishing times and enables polishes to break down properly, even on the softest of paints. It helps to extend pad life and reduce the amount of polish used, and therefore pays for itself in the long run. Works exceptionally well in hot and humid conditions, where it prevents polishes from flashing off too quickly, and is also useful in cold and damp conditions, where it prevents temperature-sensitive polishes like Menzerna RD3.02 from clumping up and becoming unusable.

Designed to be used sparingly; only a single drop is required per panel to be polished; for best results, add the drop to the centre of the pad and then place the pad on to the panel to be polished and run your machine for a few seconds at low speed to spread the oil evenly over the face of the pad.


Methodology

1. Dampen the pad thoroughly (do not over wet) as this will aid in compound/polish dispersion. You could also wet the foam and press in a folded towel, do not wring the foam as this could weaken the Velcro® backing.
2. When the pad is dampened properly it becomes flexible and much easier to use, this also helps the pad to absorb polish (capillary action) efficiently. Pad longevity may be increased as the water will dilute any solvent, paint residue (oxidation) or abrasive materials as these will degrade the structure of a pad, either by mechanical agitation or by absorption.

3. Dampened foam will be less brittle and therefore less likely to tear or shred.

4. Spread the polish / compound over the pad evenly and ensure it is absorbed into the foam, then spread that polish onto the pad by hand until the pad face becomes 75 % saturated. After polishing for a minute or two the pad will become more evenly saturated spraying water onto the surface to induce capillary action to draw more abrasives to the surface of the pad for more cut.

5. Once the pad has been seasoned (pad face is 75% saturated with product) you can reduce the amount of polish / compound applied to the pad for subsequent passes; dependent upon what you're trying to accomplish.

6. Once the pad is primed it helps by spreading the abrasives uniformly and by keeping the pad flat thus ensuring constant paint / polish contact it becomes similar to a piece of wet-sanding finishing paper, the oils in the polish provide the lubrication (like the water does in wet-sanding)

Relevant Articles

1. KBM- Pad Priming and Supplemental Wetting Agents by Kevin Brown -


2.The Physics of Polishing - 
http://togwt1980.blogspot.co.uk/2017/08/the-physics-of-polishing.html

3. Surface preparation prior to polishing - 
http://togwt1980.blogspot.co.uk/2017/07/surface-preparation-prior-to-polishing.html

Tuesday, 12 December 2017

A ‘stepping stone’ to using a coating (sub title 'Coatings 101)




Silica coatings require infrared drying lamps to ensure proper drying and product crosslinking and are better suited to a detailing studio with environmental control to prevent dust etc. To be done properly.

So although the selling price of such a service is high it does require a substantial investment.
Properly educating the customer so they understand a coatings possibilities and its limitations, while they offer better protection than waxes or sealants, as well as greater durability they still need to be taken care of properly. Using the proper washing techniques can keep their paint surface swirl free indefinitely.

As a ‘bridge between a polymer sealant and a silica coating I would suggest you look into Optimum Gloss Coat is a paint protection that creates slickness and gloss with just a few drops per vehicle. One ounce completely seals and protects 6-8 cars. This product doesn't leaves no residue and does not require infrared lamps to cross-link. Provides months of durable polymer protection with just a few drops

Optimum Gloss Coat seals and protects paint under a crystal clear barrier of cross-linked polymers. Dirt, moisture, oil, acids and UV radiation are all sealed out of the paint to maintain optimum gloss. Dependent upon climatic conditions/ use of vehicle it will protect paintwork for upwards of six months with just a few drops.

Application
Use very sparingly, Optimum Gloss Coat is made to be applied in a micro thin layer.
Always use a clean, soft micro fibre applicator to spread Opti-Seal over your vehicle.
Prep the paint before application.
Maintenance
Teaching your clients how to use Optimum Technologies (ONR) correctly would go a long way in avoiding paint surface damage like scratches, marring, swirls, and etc.

Optimum Gloss Coat is a hybrid coating consisting of SiO2 (silicon oxide) and SiC (silicon carbide). a protective clear resin coating, similar to the clear coat that already exists on your vehicle. It can be applied to all exterior surfaces. It is not recommended for glass since improper application can affect visibility. For other exterior surfaces, it is a highly effective, transparent, permanent coating that keeps your vehicle looking like new.

Optimum Gloss-Coat is an additional barrier between the elements and your vehicle's paint. The paint will retain its colour and contaminants will be blocked out to keep the paint smooth and clean. Because Optimum Gloss-Coat is semi-permanent, the paint finish must to be properly prepared before applying it.

Neither sealants or coatings will mask surface imperfections, but both will emphasise them; so prior to applying the coating, the paint should be properly corrected and then wiped down to eliminate any residual polishing oils. Optimum Paint Prep easily remove oils left behind by various polishes; Helps any wax, sealant or coating bond to the surface better; Spray on and wipe off easy application

Apply Gloss Coat to the applicator of your choice by squeezing several drops of product from the syringe.  Note that you may need many more drops initially in order to prime the applicator, but will not need nearly as much as you continue with application as the applicator becomes primed and there will be residual product on the face of the applicator.

Spread a thin layer (with an emphasis on ‘thin) onto the paint surface, working on one panel or section at a time.  When the product no longer spreads evenly, it is time to add more product to the applicator.  It wail take approximately 45 seconds to ‘flash’, dependent on environmental conditions. This is the “self levelling effect” of the product, after another minute or so, the majority of the coating will have flashed away on its own  and only the heavier spots at the top and bottom of the application strokes remain.

This is common as these areas where you start/stop your wiping usually have more built up product as it is not being spread out.After another minute or so, even most of the product will had disappeared.  All that remains at this point is to level the remaining high spots


See also "The Science Behind Coatings" -http://togwt1980.blogspot.co.uk/2015/10/the-science-behind-coatings.htm


Sunday, 19 November 2017

Finished Leather Pigmentation (Colour) Renovation



Examine the worn or faded spots on the urethane surface to decide if the condition has sufficient integrity (see Repair Compound and Mechanical Repair (Sub-patch) for renovation. Also, any imperfections you see at this stage will be amplified after the pigmentation. These can be removed with a light sanding using 3000 grit finishing paper and follow with a tack cloth and final cleaning.

The urethane pigmentation used for automobile upholstery is classified as a semi-solid permeable membrane, is a thermosetting polymer (with elastomers) it remains flexible while retaining its tensile strength, to enable it to expand and contract, following the temperature fluctuations (elasticity) of the substrate. The urethane although very resilient to abrasion wear from entering and exiting the vehicle, by using additives it still maintains its physical properties like flexibility, tactile hand and its patina

A urethanes fibre structure will stretch in all directions with no particular grain or stress pattern. The urethane surface coating will not withstand multi-directional stress, however, and when it’s flexed or stretched continuously in the same place the surface coating develops minute cracks. So any pigmentation, fillers or adhesives used must be able to maintain this flexibility, without compromising its structural integrity

Urethane Surface Cracks

As the leather hide loses moisture, it begins to shrink and stiffen. This leaves a minuscule gap (delamination) between the leather hide and the pigmented (colour) urethane coating on top of it. The urethane coating is no longer supported by the hide; without proper support, it starts to crack.

Colour change - if you are applying a pigmentation to change the colour of the finished leather; surface preparation (removal of existing pigmentation (colour) is the most important step.  
Unlike lacquer-base preparations, which close the urethane micropores, water-based products allow hydration (transpiration and evaporation of moisture) via the micropores. This enables hydration of the finished leather, maintaining its soft and supple patina after you have renovated the pigmentation.
To bring about the best renovation results, it is essential to prepare the leather before application. It will be necessary to remove most of the original pigmented urethane finish without creating thin spots or sanding all the way through the top coat.  By correctly preparing the surface and breaking down the original pigmentation, your newly applied pigment will look like an OEM applied a translucent finish.

Swissvax Leather Healer is an easy-to-apply leather pigment (dye) comprising a high number of superfine pigments combining best results with a minimum thickness pigment application so that the look and feel of the leather are not affected as it is the case with many other leather dyes. The Swissvax dye is easily applied with a small sponge and sets automatically and permanently.
The leather fine and natural structure, as well as its typical original feel, are perfectly preserved. 46 Standard Colours are available or you can also send a small leather sample and they will match your interiors leather colour.

Swisswax Leather Glaze- (finished leather top coating) new leather remains new for many years thanks to the colourless protective layer provided by Leather Glaze which drastically reduces any signs of wear. Leather driver’s seat, the smooth leather steering wheel and the smooth leather shift knob are places where the leather undergoes the most noticeable wear - even on new cars. That's why every leather interior should regularly be protected with Leather Glaze for keeping it in mint "factory" condition - an inexpensive measure and little time invested for the best interior maintenance

Surface Preparation
A few days before commencing the actual leather renovation, clean the finished leather surfaces.  As a cleaning solution, I use a formula that is used by one of the major tanneries to clean their leather. Mix a solution of 3% detergents that contains a surfactant (P21S Total Auto Wash) 10% isopropyl alcohol (IPA) and the balance distilled water. And then apply Leather Master Soft Touch (formally Vital) this is not a conditioner per se; it softens the finished leather and makes it easier to remove the seat covers.

Like all detailing task’s the correct surface preparation prior to the application of the pigmentation (colour) will ensure that it adheres correctly, and has both durability and aesthetics. Use a safe degreaser to ensure any oil and grease free surface (Leather Masters™ Leather Degreaser) this aerosol product is ideal for cleaning as it dissolves the oils and transforms them into a powder that is more absorbent than the leather. This powder is what is wiped off, cleaning and degreasing the leather. Allow the white powder to dry fully. If the powder is drying to a yellow colour, it means that there are still a lot of oils in the leather.

And then use a safe solvent cleaner (Leather Magic DT-152 or Leather Master Color Prep & Cleaner)  this chemical is formulated from several types of alcohol and milder based solvents and is used primarily to prepare the surface of leather for repair or pigmentation application. It will remove all dressings, protectants, waxes and oils from the surface, but more importantly, it will strip off the topmost layer of the finish, which cleans the surface so that it is receptive to the application of repair and colourant materials. This also creates a permanent bonding of the materials to the leather.

The solvent should be sprayed lightly over the surface, and then by using a medium soft upholstery brush will ensure any ingrained soiling is effectively removed prior to application and to ensure proper product adhesion. Using a cotton terry cloth towel, immediately wipe dry. This will thoroughly remove any foreign matter found on the surface of the leather; mild solvents also work as an excellent degreaser. After letting the solvent dry off for a few hours the area should be lightly sanded over, this will remove any cracks in the surface coating.  

Use painter’s tape and/or masking paper around anything that doesn’t require pigmentation applied
To ensure adhesion lightly sand areas to be re-coloured by using an abrasive (Scotchbrite 7447 - Maroon pad, General Purpose Hand - 320-400 grit) You’ll need to break down approximately 25µ (1 mil)  of the surface, this is important to the new leather dye can ‘key’ into the finished leather and look natural. Be consistent in how far you remove the pigmentation, it is not necessary to completely remove the pigmentation that is sitting on the leather surface. Remove dust with a tack rag or damp micro fibre towel.

Suggested Products:

Pigmentation (colour)

[: in the US pigmentation is called dye (although it’s a very different process for the application of a colourant]

Swisswax Leather Healer 
An easy to apply pigment (colour) that sets automatically and permanently, without leaving a heavy layer of pigments as often encountered with other leather tinting leaving the typical original feel of leather perfectly preserved

Certain areas of your vehicles leather interior like seats, upholstery, side mouldings and steering wheels inevitably start to show signs of wear, even if well taken care of, that spoil its overall impression. Often these imperfections are not serious and are simply the colour that has worn off or light scratches on the leather surface which can be removed and will disappear with the right application technique and our leather dye.

Swissvax Leather Healer is an easy-to-apply leather dye comprising a high number of superfine pigments combining best results with a minimum thickness of the dye application so that the look and feel of the leather are not affected as it is the case with many other leather dyes.
The Swissvax dye is easily applied and sets automatically and permanently. The leather fine and natural structure, as well as its typical original feel, are perfectly preserved. Available in 45 standard colours; provide a small leather sample and Swisswax will perfectly match the colour to your interiors leather.

Application
Spray a mist of water on the surface and then dab a terry weave towel or a small sponge into the pigmentation and gently rub it in, use small circular motions. Apply over one small section at a time overlapping the circles.

Swisswax Leather Glaze (Colorless)
Use after the renovation of finished leather’s pigmentation, this clear top-coat has a dramatic impact on leather, reducing signs of wear. The colourless, clear protective layer provides a matte finish and protects finished leather, keeping it looking 'as new'. It's a must-have product particularly in areas which get the most use, such as steering wheels, leather seats and gear stick knobs.

Leather Upholstery Abrasion (Rub) Resistance Testing
The abrasion resistance of finished leathers thin urethane covering is designed to contend with clothing abrasion from exiting and entering the vehicle. Wear from abrasion is a complex phenomenon and the information Taber Industries provides at Abrasion Testing: Taber Industries-Material Test & Measurement is meant to give you an introductory understanding of the common wear processes and their underlying causes. Having this practical knowledge will help to address the cost of failures caused by wear and abrasion.

Dirt is the real enemy of leather, acts as an abrasive every time you sit down or change your position while driving. Abrasion wear is due to hard particles or hard protuberances forced against and moving along a solid surface. These hard particles might be commercial abrasives like silicon carbide and aluminium oxide, or naturally occurring contaminants like dust particles and sand [crystalline silica (quartz)]. If the abrasive particles are allowed to roll, rolling abrasion or three-body abrasion occurs.
This can lead to catastrophic wear, which is a rapidly occurring or accelerating surface damage, deterioration, or change of shape caused by wear to such a degree that the service life of a part is appreciably shortened or its function is destroyed.

ASTM D7255 Standard Test Method 
Abrasion Resistance of Leather (Rotary Platform, Double-Head Method) this test method covers the determination of the abrasion resistance of leather using the rotary platform, the double-head tester (RPDH).



Does Water Breading Equate to Paint Protection


Water Beading - http://togwt1980.blogspot.co.uk/2017/11/does-water-breading-equate-to-paint.html

Beading is a surface interaction between water and the paint surface; dust or dirt particulates, oxidation, environmental pollutants, and etc. interfere with the surface tension, thereby disrupting the beading. Beading that is left to evaporate on a car will lead to water marks; if there is acid or alkali contamination in the water.

Dependent upon the water source; clean rainwater has no harmful effects; but cognizant that water beading whatever its aesthetic value doesnt equate to surface protection. The average unprotected water-based paint absorbs approximately a pint of water; dependent upon what’s in the water this may be harmful.

Pros: the aesthetics of water beading are sought after by many detailers. Many detailers believe that if there is water beading on a paint surface the LSP is providing protection. Nothing could be further from the truth; water beading is primarily due to surface tension

But if a product beads on initial application and after a period of time starts to sheet water (or vice-versa) it is normally indicative that the wax/sealant protection has diminished.

Cons: dependent upon the water source clean rainwater has no harmful effects, acid rain is inert until heat is added and then it become corrosive, the water from a standard household supply usually contains minerals like calcium (Ca) magnesium (Mg) and alkaline. The beads have a very small surface area, so the sun will increase the surface temperature very rapidly once these form reactivity starts (moisture, heat and an acid or alkaline) and once they are dried they will cause etching (a shallow indentation) of the paint surface

Be cognizant that (a) Dust and road soil will also have a negative impact on water beading this is often mistaken as paint protection product failure. (b) Durability can fluctuate dependent upon environmental conditions and the products used between the application of a wax/sealant and the use of quick detailers (QD), car wash concentrate that contains a wax, spray wax, etc)

Does water beading equate to durability or to actual surface protection?

Beading is a surface interaction between water and the paint surface, both a protected or just a clean painted surface. Dust or dirt particulates, oxidation, environmental pollutants, and etc interfere with the surface tension, thereby disrupting the beading

Most waxes/paint protection will bead until enough surface tension is created, and then it will sheet as the volume of water increases. Beading of rain water on the surface of a waxy surface, such as an automobile is due to surface tension. Water adheres weakly to wax and strongly to itself, so water clusters into drops. Surface tension gives them their near-spherical shape, because a sphere has the smallest possible surface area to volume ratio.

Nearly all wax and sealant products exhibit water beading or sheeting initially (in fact so does a clean paint surface without an applied protection) this is due solely to surface tension, once the protection breaks down (abrasion from water, road dirt/grime and other airborne pollutants) it will cause a reduction in the surface tension and the beading will revert to its former level

Slickness is also not an indicator of protection; as it comes from the (silicone) polymers and oils, once applied and exposed to the environment they start to evaporate / deteriorate. If your goal is maximum protection, don`t use water beading/sheeting as an indicator; while it’s true that it is a visual indicator that a wax / sealant previously applied is still present it does not guarantee that it’s actually providing protection.

Hydrophobic beading on a paint surface is aesthetically pleasant, and many people equate beading with protection; there is a long standing myth- that as long as a paint surface maintains beading it’s being protected from the elements (much like the myth that the more soap produces suds the better the cleaning effect) There are many things that will affect the shape of a water bead on a surface; since gravity, surface tension and the surface energy of the coating all play a part.

Contact Angle

To test your paint protection you must measure the water beading of your paint (height, contact angle and diameter) without any polish/wax applied. Next, measure the water beading of your paint (height, contact angle and diameter) within 24 hours after initially applying your polish/wax.

This is your starting point. This will also be the gauge for determining the water beading (longevity, duration and changes) for that specific product. As the water beads start to diminish (get wider and shallower and loses contact angle), the polish/wax and its film protection factor is going away, Once the water beading is the same as before you apply your product, the polish/wax and its protection are gone

Dust and road grime will have a very negative effect on surface beading than any other factor. The effect of this is often misconstrued as wax failure when this isn`t the case.

Durability [: able to exist for a long time without significant deterioration] varies depending on various environmental factors, including but not limited to:

Product is applied to a clean, cool and dry surface

Product was allowed to cross-link and form a molecular bond with the paint system

No oils or water (including moisture, dew, etc) was introduced to the surface before it has formed a molecular bond

What the environmental conditions (ambient temperature etc) are where the vehicle is stored

The kind of airborne contaminants the vehicle is regularly exposed to

Frequency of washing and kind of car wash solution used (i.e. detergent strength, etc)



Water beading

[: convex beads that have a small, tight symmetrical shape due to cohesion] 

Although you cannot equate a products beading ability to protection and durability, if an applied product continues to `bead` water, one wash after another, then that would prove that whatever it is that is causing high surface tension is not washing off.

How can you tell when a paint surface protection has diminished to a point that it is no longer being protected?
  
Scientific explanation

Water (H2O) is a polar molecule, composed of two hydrogen's (H2) atoms bonded to a single oxygen (O2) atom. Water molecules adhere to each other, this is called cohesion.

Water molecules also can be attracted to other substances, such as metal or dirt, especially if they have some static charge on them, this is called adhesion.

Some substances are not attracted to water and even repel it. These include oils, fats and waxes; these are called non-polar substances.

When water falls on a surface where no oils are present, the forces of adhesion and cohesion are almost in equilibrium, and the water spreads out

A wax or sealant, when applied properly to a clean paint surface, fills in the larger surface fissures and layers the whole surface. The chemical structure of the wax prevents water from penetrating to the surface of the car. Because the wax itself is hydrophobic (literally repels water), the forces of adhesion are much less than the forces of cohesion. So, water is more likely to bead higher and rounder than on a surface without wax/sealant

Non-scientific explanations

a) If the paint surface feels dry (your hand or a towel meets resistance), it’s an indication that there’s nothing left between you and the paint finish. Glazes, waxes and polymer’ create a finish with less friction (surface tension) than the paint itself.

b) A suggestion from a polymer product manufacturer Sal Zaino - To test your wax/sealant you must measure the water beading of your paint (height, contact angle and diameter) without any polish/wax applied.

Next, measure the water beading on your paint (height, contact angle and diameter) within 24 hours after initially applying your polish/wax. This is your starting point. This will also be the gauge for determining the water beading (longevity, duration and changes) for that specific product.

As the water beads start to diminish (get wider and shallower with a diminished s contact angle), the polish/wax and its film protection factor is going away, Once the water beading is the same as before you apply your product, the polish/wax and its protection are gone

Conclusion- water beading is indicative but not conclusive proof of protection

The hydrogen bond between water molecules is the reason behind two of water's unique properties: cohesion and adhesion. Cohesion refers to the fact that water sticks to itself very easily. Adhesion means that water also sticks very well to other things, which is why it spreads out in a thin film on certain surfaces, like glass. When water comes into contact with these surfaces, the adhesive forces are stronger than the cohesive forces. Instead of sticking together in a ball, it spreads out.

Surface tension is a property of the liquid and not of the surface. This means that the molecules on the surface of the water are not surrounded by similar molecules on all sides, so they're being pulled only by cohesion from other molecules deep inside. These molecules cohere to each other strongly but adhere to the other medium weakly.

Water beading is created due to a high surface tension on the vehicle. The higher the surface tension, the smaller and tighter the formation of the beading will be. The lower the surface tension, the bigger the beads will be. Surface tension is the ability of a liquid to adhere to its neighbouring water molecules. Once the surface water beading changes shape (from the initial small tight beads to a lager ‘flat’ bead or the water sheeting becomes much ‘slower’ the painted surface is losing its tension.

There are however exceptions: a freshly painted surface will bead with no wax or sealant on it and a just-polished vehicle will also bead with no wax or sealant. This is due to the oils that are present, that promote beading.

Changes to the surface tension

The water tension changes throughout the life cycle of the surface protection and maybe a more indicative indicator of the performance. Indications that the products durability may be diminishing- (contact angle varies) when the water beads become noticeably larger in diameter with a flat, concave or an irregular shape usually indicate that the surface tension of the wax or sealant is diminishing. Or when dust, dirt or bug residue becomes more difficult to wipe off with a quick detailing spray are indications that it may be time to renew the protection

It could be something as simple as a dirty surface or contamination, which increases the surface area. If the surface is clean then `something` on the surface itself has changed. In terms of a wax or sealant, this likely means that some of the protective film (the part that reduced the attraction of water) is gone. This could suggest that the paint protection product is beginning to lose its effectiveness.

 d) Slickness- slide a micro fibre towel across a horizontal surface to see how much resistance there is, if there has been a significant reduction from what you experienced previously the durability is probably diminishing

Water Sheeting

e) Sheeting (hydrophilic) - the self cleaning (sheeting) ability of the hydrophilic polymer seems to be much better than the hydrophobic organic wax (beading) effect, as it may accelerate the oxidation when drying after rain.

There are some disadvantages to water beading (hydrophobic) as opposed to the sheeting effect (hydrophilic) of a polymer, when they are dried by ambient temperature they cause water spots (if the rain contains calcium it will leave a white residue) The other is there could be over a pint of liquid trapped within the beads over the paint film surface area, if they contain acid from industrial fall out (IFO) this could increase the time the acidic solution remains on the paint surface compared to water sheeting

The beads have a very small surface area, so the sun will increase the surface temperature very rapidly; many chemical compounds react to slight heating and an oxidizing process. Now you have acid + water + oxygen + ozone + heat; all of which equates to reactivity, which produces a highly concentrated acidic solution, causing concave indentations (acid etching) to the paint surface

Any product can be reformulated with active surface agents (surfactants) either ionic (sheeting) or non-ionic (beading) that alters the surface tension and causes water to sheet or bead to satisfy consumer demand.

But if a product beads on initial application and after a period of time starts to sheet water (or vice-versa) it is normally indicates that the wax/sealant protection has diminished.

The beads sitting on the surface can cause spotting or etching, whether in the coating or the paint. If there are contaminants in the water like acid rain or other stuff, it can work its way to etch all the way to the paint.


We have established that both surface energy and contact angle are crucial to the efficiency of a paint protection product (ignore surface pencil hardness as they are a very minor factor) Determining the surface energy can be achieved by measuring contact angle or by use of Surface Energy Test Liquids or Pens (Dyne level testing).

This form of measurement is based on the ISO method for measuring the surface energy. Surface energy may be defined as the excess energy at the surface of a material compared to the bulk. Every solid surface has a specific and measurable surface energy. 

The unit of measurement used is the Dyne/cm² or mN/m.

When the Dyne level test liquid is applied to the surface, the liquid will either form a continuous film on the surface or pull back into small droplets.surface or pull back into small droplets. If the Dyne test fluid remains as a film for 3 seconds, the substrate will have a minimum surface energy of that Dyne Pen liquid value (Dyne Test Pen fluids are available in values from 30 to 70 mN/m. Should the Dyne test liquid reticulate or draw back into droplets in less than 1 second then the surface energy of the substrate is lower than that of the Dyne Test Pen liquid itself. 

The exact surface energy (Dyne level) can be determined by applying a range of increasing or decreasing values of Dyne test pens.
To test the viability of a coating requires measuring the surface energy (surface tension).
One of the first steps to ensure a paint coatings viability is to determine the dyne level. Dyne Marker pens can be used to measure the surface energy of coatings and films and other non-absorptive substrates, this method parallels ASTM Std. D25781

A Dyne marker pen is an accurate tool to measure the surface tension level or Wetting Tension of a paint protection coating surfaces. There are different ranges of dyne kits based on your requirements covering the specified range of dyne levels in two dyne increments.
In general, the ability of a substrate to anchor a coating, or adhesives is directly related to its surface energy. If the substrate surface energy does not significantly exceed the surface tension of the fluid which is to cover it, wetting will be impeded and a poor bond will result. Thus, for most paint protection coatings need to be treated to 36 to 40 dynes/cm (see Note 1)

Test Methodology

For the results of this test to be meaningful, the following four points are absolutely essential and must be followed:
a) Do not touch or in any way contaminate the surface to be tested. Dirty surfaces lose their wettability.
b) Do not use contaminated or outdated marker pens.
c) Never retest the same location on a sample; move along the sample, or pull a new one.
d) Store and use marker pens at room temperature.

2.0 Method
a) Pull test sample. Be sure to pull a good specimen; surface aberrations cause poor results. For an extruded film, one entire web cross-section should suffice. Do not touch the surface.
b) Place the sample on a clean, level surface. If necessary, anchor the edges to avoid curling or other deformation.
c) Record ambient temperature and relative humidity. If sample temperature differs from ambient, allow it to stabilize.
d) Test at least three points across the sample; 1/4, 1/2, and 3/4 across the film section. It is good practice to test the outer edges as well. For non-film materials, test locations must be determined in-house.

Determination of Wetting

1. Choose a marker pen at a dyne level you believe is slightly lower than that of the test sample.
2. Press applicator tip firmly down on subject material until the tip is saturated with ink.
3. Use a light touch to draw the pen across the test sample in two or three parallel passes. Disregard the first pass(es); to flush any contamination from the tip, and to ensure that the test fluid layer is thin enough for accurate measurement, evaluate only the last pass.
4. If the last ink swath remains wetted out on the test sample for three seconds or more, repeat steps 2 and 3 with the next higher dyne level marker. If the last ink swath beads up, tears apart, or shrinks into a thin line within one second or less, repeat steps 2 and 3 with the next lower dyne level marker. If the ink swath holds for one to three seconds before losing its integrity, the dyne level of the marker closely matches that of the sample.

Finally, a few qualifying words. Surface energy is critically important to many converting operations. Unfortunately, it is not the sole determinant of product suitability. Other factors, such as surface topography, coating rheology, and chemical incompatibility, must also be considered.


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