Polish / Compound
[: Polishing is the process of creating
a smooth and shiny surface by rubbing it or using a chemical action, leaving a
surface with significant specular reflection and minimal diffuse reflection.
When the surface is magnified thousands of times, it usually looks like
mountains and valleys. By repeated abrasion, those "mountains" are
worn down until they are flat or just small "hills." The process of
polishing with abrasives starts with coarse ones and graduates to fine ones.]
What polish should I use?
Where do you start with this
question and as much as I dislike answering with a question; a little more
information is required in order to give an even half-way correct answer. Answering
this question with ‘use a compound, a rotary action machine and a wool pad, is
like the proverbial ‘use an acid on it’, which is probably overkill.
The most obvious
one is ‘what did the test panel show you’?
It takes many years of
experience to be able to judge with any accuracy the abrasive / pad type/
machine action without utilizing the ‘Test panel method’ that will remove the
scratches. One of the things I was taught many years ago was to always use the
least aggressive / invasive product first.
I’ve spent many hours
meeting and speaking with Engineers, paint chemists, product formulators, and
abrasive manufacturers and polishing pad manufacturers and have gained insights
into paint surface polishing that has afforded me an understanding of how all
these things interact to form a process, on a scientific level paint polishing
is the sum of all these parts.
Polish a paint surface
correctly (regardless of the machine we are using) the goal is leave a series
of scratching that is so fine that it becomes imperceptible to the naked eye.
The following ingredients are formulated in a polish;
·
Water - the more water there is in a compound, the softer it
will be
·
Solvent - act as a carrier system and to make the other
ingredients soluble. By adjusting the type of solvent, you will determine how
long it takes the product to dry.
·
Abrasives - used to remove surface swirls and marring Abrasives
can be soft or hard; the most common abrasive used is silica however; many
formulators are also using aluminium oxide.
·
Diminishing abrasives - break-down due to friction and then go
on to burnish the paint to a bright shine
·
Non-diminishing abrasives - you polish until the defects are
removed, not until the polish has diminished
·
Surfactants - defined as a material that can greatly reduce the
surface tension of liquids
·
Colouring - is used strictly for customer appeal, traditionally
compounds are tan or olive in colour, so most manufacturers colour their
compounds accordingly.
·
Fragrance - is only for customer appeal
·
Waxes - a small amount is used to produce gloss and fill small
imperfections. And is sometimes used for surface lubrication
Emulsifiers - an oil/water emulsion is used
to stabilize the product and make it easier to use a polish or compound is a specially
formulated emulsion of materials designed to remove paint surface imperfections
such as scratches, oxidation, stains, and acid rain etching. Compounds are
formulated in both liquid and paste form, and generally contain more aggressive
abrasives than are found in polishes. The compound step is usually followed a
polish and then a polymer sealant, or a glaze, or and/or a Carnauba wax.
Whether liquids or a paste,
an apt description of a compound (800 -1500 grit); is ‘liquid sandpaper’ they
are formulated from a few basic components: water, oil, and solvent,
diminishing abrasives, surfactants, colouring and fragrance. Placing a small
amount between your finger tips will no longer give an indication of compounds
abrasiveness; this is due to the particles being emulsified in oil and not
released until subjected to friction
The main ingredient in a
polish or compound is the abrasive; wither diminishing or non-diminishing, the
type of abrasive, their size, hardness and shape. The abrasive ability of a
polish / compound is also affected by the type of lubrication (polymer, mineral
oil, etc) used Some very abrasive compound polishes don’t feel abrasive to the
touch because the particles are formulated in a water-in-oil emulsion for the
cooling-lubricating process and are not released without friction or pressure /
time.
These factors will determine
what that polish will ultimately do to the paint surface, the larger the
abrasive, the more aggressive it will be on the paint surface. The most common
abrasive used is silica, which is much, much harder than aluminium oxide;
however, many formulators are also using aluminium oxide.
Most good quality compounds
and polishes contain abrasives and are either silica or aluminium oxide, or a
combination of both. Think of them as liquid sandpaper, buffered or cushioned
in lubricating oils that are formulated with solvents, water and 0.3 –0.4µ
(micron) abrasive particles, in an emulsion that enables both cooling and
surface lubrication, that spreads and tumbles the abrasives that diminishes
with friction, or breakdown with pressure.
The paint film surface also
requires occasional polishing to maintain a pristine paint film surface and to
ensure that any accumulated microscopic contamination in the paint surface
crevices does not cause paint staining and that this dirt is not sealed into
the paint by the application of wax or sealant.
The use of abrasive type
polish / cleaners should always be restricted to specific problems. Most
original paint finishes are tougher on the outer surface than the layers
underneath. The outer layer (which contains the paints UVR protection) should
be preserved as far as possible.
Water
The more water there is in a
compound, the softer it will be. That is the difference between a liquid and a
paste compound. Neither is better than the other in terms of performance. It
really comes down to what the detailer prefers.
Solvents
There are basically three
solvents that can be used: mineral
spirits; kerosene; and naphtha. Mineral spirits are usually a quick-drying
solvent that will make the compound dry quickly, speeding up the job. However,
it will also increase the possibility of burning the paint if used incorrectly.
Kerosene, on the other hand, is a slower-drying solvent that reduces the
tendency to burn paint. It will, however, increase the work time with the
compound.
What happens when the
solvents evaporate? Polish and many
surface protection products are formulated with oils to enhance the surface or
to nourish leather surfaces, neither of which is necessary
The purpose of oils is to
provide lubrication, the amount used will determine the working time of the
compound. Oils provide surface lubrication to help it spread; it is made into
an emulsion with solvents that make the product into a pliable liquid. The
emulsion of oil and its catalyst, a solvent, only require air to outgas as the
oil/solvent solution will vaporise, sometimes a very thin film of oil is left
on the surface, which is usually removed when the surface is wiped with
isopropyl alcohol (IPA) this is important if the following product is a polymer
as it won’t bond as an oil film acts as a buffer to the cross-linking process.
Oil-in-Water
Emulsion
[: a dispersion of small globules of one liquid in a
second liquid with which the first will not mix, i.e. an emulsion of oil in
water]
Synthetic
polymers manufacturers are getting away from using petroleum distillate based
silicones and are now using Polydimethylsiloxane silicones to produce a mild
oil-in-water emulsion. Being primarily water based these are safe for all types
of pant and are biodegradable.
Chemists
also use these water-in-oil emulsions to reduce emulsion particle size, to
stabilize the emulsions, and to improve spreading and coverage of the polymers
products. Emulsion polymerisation takes place in an emulsion typically incorporating
water, monomer, and a surfactant. The most common type of emulsion is an
oil-in-water emulsion, in which droplets of monomer (the oil) are emulsified
(with surfactants) in a continuous phase of water.
If
the polymerisation is carried out in the absence of surfactants, it is
generally known as a suspension polymerisation. The advantages of emulsion
polymerisation include: more complete surface coverage to prevent contact
between unprotected areas, viscosity remains close to that of water and is not
dependent on Covalent (molecular) weight and the final product can be used as
is and does not generally need to be altered or processed.
Emulsions
Emulsifiers and emulsions
can seem like mysterious concepts but actually are very common. Milk is an emulsion
of milk fats and solids held in suspension by an emulsifier called casein. Oils
and polymers are often suspended in an emulsion and used as a carrier system in
waxes and polymer sealants.
Oil will not spontaneously
mix with water, but the presence of a surfactant provides a decrease in surface
tension that allows the formation of small droplets of oil in the bulk of water
(or vice versa) Compounds, polishes, waxes and sealants are most commonly
comprised of very tiny droplets (emulsion) of solvents, abrasives and active
ingredients held in suspension in a water solution by emulsifiers
Surface Filling / Masking
Abilities
Every polish that uses oils
or polymers for lubrication will fill
surface marks that are not removed and mask defects. If you don’t remove the
lubricating oils (Anhydrous Isopropyl (99%) Alcohol (AIPA) wipe-down, then you
are by passing the post polish inspection and the oils left behind will mask
the defects.
Note – some polishes contain specific
products (i.e. Kaolin (China clay) or Diatomaceous earth) to mask surface
marks, this type of filler will also be removed by the IPA wipe-down process.
Polishing
Abrasives are made from
chromium oxide, aluminium silicate, zirconium silicate and carbides; their
abrasive ability depends on the shape of its particles, not necessarily its
size. A medium size, spiked abrasive will tumble and dig. However, a large
round crystal won't leave a deep scratch.
A large hard abrasive may
also be brittle. It will cut once and lose its edge, while a softer small
abrasive will hold its edge and keep on cutting. Many smaller abrasives have
wedge shaped edges protruding from triangular crystals. These can easily slice
through an oxidized layer of paint
Polishes are a very essential product
for the overall appearance and condition of the paint finish.
There are
abrasive polishes formulated to remove paint finish issues such as oxidation or
other paint surface imperfections such as surface scratches. Light polishes
contain either mild abrasives and / or a chemical cleaner (solvent) most mild
abrasive polishes will remove medium scratches or surface imperfections,
whereas a strong abrasive compound polish rely both on a chemical cleaner
(solvent) l and mechanical abrasives to rectify more serious paintwork issues.
Proper washing and drying
techniques are the best way to avoid the need for polishing. Using a chemical
paint cleanser versus polishing on a clean finish to simply remove old
wax/sealant is another. And always follow the rule of using the least abrasive
polish and pad combination (working smarter not harder)
Polish and Wax are very
different and should not be confused, although the retail industry has blurred
them together in marketing. This is not generally
possible because the substances perform separate functions; in general terms a
wax is used for protection and a polish is abrasive and used for surface
correction. The word ‘polish’ is used because when you apply wax to a vehicle
you are ‘polishing the car’
[Detailers]
A polish is an abrasive product
that removes imperfections and levels a surface to enable the light to reflect
evenly.
[General
public] The word shine is
also used in the context "I polished with a wax to make it shine" hence the confusion between
the two.
Paint Polishes and Protective
Coatings
·
Compound
– an aggressive grade of polish used to remove deeper scratches
and for paint renovation
·
Polish
– an abrasive compound that removes surface scratches and
impurities, it provides shine and prepares it for a wax or sealant protection.
·
Paint
Cleaner (pre-wax cleaner) – a chemical cleaner that contains mild
abrasives (i.e. Kaolin (China clay) or Diatomaceous earth) that is used to
clean a paint surface but they will remove wax residues, embedded dirt and light stains from your paint, but they will not remove ingrained
surface scratches. Use paint cleaner after detailing clay and before
waxing.
·
All
in One) – very
similar formulation to a paint cleaner, the main difference is that an AIO type
product provides limited surface protection
·
Glaze –
used by detailers for show car to obtain maximum light reflection. They produce
a “wet" look to the surface with oils to maximize surface gloss and may
contain fillers (Kaolin or China clay) to hide minor defects not removed by
polishing or for use when the paint is thin and you don't want to remove any
more, even if it is microns. A glaze is a very fine (usually) non-abrasive
polish. Some glazes are safe to use on fresh paint, as they allow fresh paint
to outgas. They will provide little if any surface protection.
·
Wax – an
organic or synthetic protective coating that is applied to the exterior surface
of an automobile to improve shine and prevent oxidation
·
Sealant – a
polymer sealant comprises an open linked molecule, which forms a bond with the
paint, this is the main reason for their durability; these open linked polymer
molecules join together to create an elongated mesh like effect that reflects
light efficiently due to their inherent flat surface. Because they are usually
very transparent they transmit the surface colour faithfully, but they have
very little depth resulting in what is perceived as a very bright, flat silver
glow
·
Quick
Detailer - Detailers spray (QD) have many uses; to aid in final drying to
remove water spots, used with Zaino (Z6) to help ‘smooth-out’ finish between
coats of sealants, it also removes smearing from the over-use of product. Use a
1:1 solution of a detailing spray and distilled water as it makes them easier
to apply and more economical. To remove heavy dust use Optimum No Rinse (ONR) a
waterless wash as it will provide a lubricant that a detail spray doesn’t.
Waxing or applying a polymer
sealant to a surface that has not been properly cleaned will only result in a
shiny layer over dull, dirty paint - not the deep smooth, optically perfect
crystalline shine that is obtainable.
Abrasives
The ability for a polish to
"cut" depends on the shape of its crystals or particles, not
necessarily its size. A medium size, spiked abrasive will tumble and dig.
However, a large round crystal won't leave a deep scratch.
Aluminium oxide has a
hardness factor MOHS 9 and will not break down during polishing. Rather the
larger clusters of aluminium oxide reduce in size.
A large hard abrasive may
also be brittle. It will cut once and lose its edge, while a softer small
abrasive will hold its edge and keep on cutting. Many smaller abrasives have
wedge shaped edges protruding from triangular crystals. These can easily slice
through an oxidized layer of paint
Types (Grades) of Polishes
A surface scratch that will
`catch' your fingernail is approximately 0.04 Mil (1.0 µ Microns) deep will
usually require wet sanding and refinishing. Other than that > 1000 grit
scratches can be removed with a polish/compound and a machine polisher.
The ability for a polish to
"cut" depends on the shape of its crystals or particles, not
necessarily its size. A medium size, spiked abrasive will tumble and dig.
However, a large round crystal won't leave a deep scratch.
A large hard abrasive may also be
brittle. It will cut once and lose its edge, while a softer small abrasive will
hold its edge and keep on cutting. Many smaller abrasives have wedge shaped
edges protruding from triangular crystals. These can easily slice through an
oxidized layer of metal.
Liquid polishes tend to perform
better than pastes because they allow you to use the oxidation you're removing
as an abrasive. The oxidation will be no coarser than the abrasive in the
polish, and since aluminium oxide is second only to a diamond abrasive, it makes
an ideal cutting compound.
1.
Compounds
- are the most aggressive,
most abrasive type of polish and will remove the largest amount of clear coat
in the shortest period of time. Compounds are commonly used on severely
neglected vehicles and to clean up wet sanding marks. Compounds will almost
always leave behind some marring, hazing, or holograms and should always be
followed up with a finer polish or multiple polishes.
2.
3.
Abrasive
Polishes – the most polishes that correct moderate paint imperfections fall
into the category of an abrasive polish. They are a step below compounds in
terms of aggressiveness and usually do not finish down as well as a finishing
polish. On most paints, it is recommended to follow up an abrasive polish with
a finishing polish to remove any micro-marring, hazing or holograms as well as
increase the depth and gloss. Some abrasive polishes are capable of finishing
on certain paint.
4.
5.
Finishing
Polishes - will remove very minor imperfections in the paint, such as
micro-marring, hazing and holograms. A finishing polish is formulated with a
very mild abrasive that finely polishes the paint surface and effectively
enhances light refraction and reflectivity. They are also used to burnish
(jewelling) the paint to achieve an exceptional level of gloss and depth.
6.
7.
Paint
Cleaners - are designed to enhance the depth and gloss while properly
preparing the paint for a sealant or wax. Sometimes paint cleaners can have
micro abrasives or they can be non-abrasive. They typically will not remove imperfections
that require levelling the clear coat, but can remove some oxidation and
mineral deposits.
Always choose the least intrusive product, it is preferable to
polish 2-3 times to restore the paint film surface than to use an unnecessarily
abrasive machine polish / foam pad combination. Before commencing polishing do
a test panel on the car, once you have achieved the desired results with the
chosen polish / pad combination proceed
Difference between
Diminishing and Standard Abrasive Polishes
Diminishing Abrasives Technology
A non-linear abrasive that
require kinetic (or dynamic) friction - while the majority of polishes on the
market use a form of diminishing (non- linear) abrasive, which you polish to a
‘haze’ (when a polish "flashes" from a liquid paste to a light
semi-dry haze, much like a coating of Vaseline®) the diminishing polish has
then broken down and is ready for removal. Diminishing abrasives, as the name
suggests; t he abrasives become smaller with friction, and therefore go from
removing paint defects to polishing the paint, which produces the shine.
If you don't break them down
sufficiently, you are just grinding those abrasive particles into your paint,
without polishing it, which can leave behind marring and other paint surface
imperfections. So it’s important to know when a polish has broken down because
if you take it too far you will re-introduce surface marring. During the
polishing process, trace amounts of paint and / or oxidation is removed; this
can cause the debris and the polish to “clump” together. This can cause a haze
to the paint surface, a wipe-down or a paint cleaning product will eliminate
this.
Pros - Menzerna diminishing
abrasive polishes are formulated with a long lasting lubricant. The abrasives
break down before the lubricating oils dry out, thereby giving polish a longer
working time and producing less abrasive dust and avoiding dry buffing.
Cons - Menzerna lubrication
oils can be really resistant to removal; it may take 2-3 IPA wipe-downs.
Non- Diminishing Abrasives Technology
A linear abrasive that
require time and pressure - unlike diminishing abrasives, which require kinetic
(or dynamic) friction to enable the abrasives to 'break-down to obtain the best
possible finish (and avoid holograms) non-diminishing abrasives react very
differently. It will be as abrasive as you want it to be, time and pressure
applied (linear abrasive) being its working criteria.
Linear abrasive polishes /
compounds provide a constant cutting abrasive, as the abrasives remains uniform
in size throughout the polishing process, so you need to check the surface
often. They should be used with a cutting foam or wool pad until the defects
are removed (1200 – 1500 RPM) but do not allow the polish too completely dry
(as this will also produce holograms) and ensure that pad surface is cleaned by
removing paint / polish debris regularly This type of compound / polish process
usually requires subsequent polishing step(s) to further refine the finish and
to produce a shine
Cons - the lubricating oils
dry out, thereby providing a shorter working time, producing more abrasive dust
and the possibility of dry buffing
Amount of Polish
Place a small amount (approx
3 x 1/16th-inch diameter or a 1 ½ x 1 ½ -inch X) of polish onto the centre of a
clean primed pad. Approximately 1.5 – 2 oz for a mid-sized vehicle
Polish / Compound
Application
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 and ensure it is absorbed
into the foam, apply some pressure to the surface and scrape any excess product
from the pad
Apply the compound or polish
to the surface and spread the polish using the foam pad with the (Orbital
Polisher) machine off. This coats the pad and the surface being polished with
product to prevent scratching or hazing the finish, then place the foam pad
flat on the surface and turn the machine on. Do no, under any circumstances,
turn the polisher on with any portion of the foam pad dry as this will produce
hazing.
Most polishes are formulated
by emulsifying a powdered abrasive in a carrier system (oil / solvent) the
right amount of pressure / friction heat is vital to allow the polish /
compound abrasives to level the paint surface and remove surface scratches /
marring
Dry buffing
Dry buffing (polishing)
refers to when the polishes lubricants run out; non-diminishing abrasives will
start to emits a white dust, diminishing abrasives start to become translucent
(similar to Vaseline on a paint surface). Once you polish much beyond these
points is when friction from dry-buffing can lead to you creating fine
scratches and dullness or even burning the paint.
Polish Methodology (polishes
and pad selection)
Diagnosis is the key; not
guesswork; examine the vehicles bodywork, a ‘bag-test will ascertain the
need for detailer’s clay, and a 3M Sun Gun or a Brinkman light will help you
find any evidence of surface blemishes i.e. swirl marks and scratches.
The most important first
step in the process of paint surface detailing is diagnosing the paint surface;
density of clear coat (hard or soft) or single stage paint, surface condition;
ascertain the severity of the surface blemishes with an inspection light and
the paint thickness available. The paintwork should be evaluated with a paint
thickness gauge to see what thickness of clear coat remains before you decide
how much paint renovation can be safely carried or wither paint preservation
would be the appropriate option, before you proceed, measuring with a paint
thickness gauge will dictate the choice and abrasiveness of polish / compound
for correction or renovation level required or indeed possible
Always follow the rule of
starting with the least abrasive combination, i.e. a machine polish and the least
aggressive foam or wool pad (working smarter not harder) The most important
first step in the process of paint surface detailing is diagnosing the paint
surface; density of clear coat (hard or soft) or single stage paint, surface
condition; ascertain the severity of the surface blemishes with an inspection
light and the paint thickness available.
Measuring with a paint
thickness gauge will dictate the choice and abrasiveness of polish / compound
for correction or renovation level required or indeed possible. Assess the
correction level working through the range of polishes from the lightest
abrasive upwards until the desired level of correction is reached. Selecting
the correct pad / polish combination for the vehicles paint / defects can take
just as long as the paint correction process
Test Panel
When removing defects from
the paint surface, consider not only which polish / compound you'll be using,
but how you'll be using it. Your choice of machine speed, pad construction, pad
size and applied pressure will all impact the abrasive abilities of the
polishing liquid.
Decide on a one, two or
three step polishing routine and select a suitable pad. After testing a section
to confirm this method, select an area of 18 x 18-inches and tape it off with
painter’s tape, as this is an optimal working section to perform a product test
spot; this will help establish a process that will produce the best possible
finish, once this is established repeat the process over the entire paint
surface.
Select
a ‘typical’ area - (one that represents the type of defects that you want to
remove) and starting with the least abrasive polish and / pad combination and
then proceed until the defects are removed. This is the polish / pad
combination you’ll need to use
Current Information
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 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.
About the author - http://togwt1980.blogspot.co.uk/2015/05/about-author.html
This is not a product vendor’s
catalogue, nor am I a vendor pretending to be an educator, as there are a lot
of companies that are now sponsoring detailing forums, giving advice and
preaching that only the product they sell or manufacture are suitable. In reality
they are just advertisements, with the appearance of educators, mere salesman.
Those who have something to sell can be very persuasive, often using marketing
pseudo-science (i.e. blurring the
distinction between science and fiction) to make a great case while completely
ignoring meaningful facts, like their product adds nothing of real value.
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 box" 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 I have found that they will perform the task more than adequately, hence
the personal recommendation, 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
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