Dummies guide to car detailing - Part 3

Wax or Polish? What is in a name?

Though both terms are used interchangeably, there is a fine difference between wax and polish.

In generally, Polish is a mild abrasive substance which will clear the paint surface of mild oxidation and smoothly micro sands the surface and gives the surface a wet, deep glow.

On the other hand, wax is a protective coating - it covers the micro pores in the paint and seals it and helps the paint to shine. A wax does not have cleaning properties, and applying a coat of wax on a non clean surface is not at all recommended because wax will seal the minor aberrations.

Though generally polishes are abrasive, there are exceptions. meguiars claims that they use a secret polishing oil and their 'pure polish' is non abrasive.

To Polish or not to polish?

As you may have already understood, most polishes are abrasive materials so naturally there will be doubts like why should we use abrasive materials on the paint. The answer is simple - to clean the paint surface and to remove swirl marks, to improve surface reflections and to improve the paint gloss.

Generally, if the car is not used in a heavy polluting environment, you should wax your car once in 3 ~6 months (depending on the wax) and should polish the car in once in a year.

The definition of polish is: "Polishing is the process of creating a smooth and shiny surface by rubbing it or using a chemical action" (from Wiki). Polish is the process of making it smooth by friction, but more often than not, it is not the heat which is produced using the friction which does the work, but the friction itself. Most polishes are emulsions of powered abrasive in a carrier. Heat causes paint dull, so wet polishes eliminate the heat induced by buffing action.

Different polishes have different cutting ability, and this cutting ability determines the amount of paint removed in each hand or machine stroke.

There are different kind of polishes available in market - we must choose a polish based on our needs.

Typically, based on technology, we can divide polishes into polishes which uses 'Diminishing Abrasives Technology' and those which uses 'Non-Diminishing Abrasives Technology'.

I am not going into detail of the difference between these two, but if any guys out there want to know more, feel free to ask.

The market have dime a dozen polishes claiming to work miracles on your car paint finish - we really need to know what we are buying before we try them on our paint surface. For example, the outcome of a coarse finish polish and a fine finish polish are way apart.

Some polishes are specially formulated for machine use, while some are for hand use. the difference between them is the way the abrasive materials in the polish 'breaks-down' during the use. As I said earlier, polish in an emulsion and the carrier act as lubricant too.

While polishing, the abrasive materials break down into finer particles to do the work. If you use a machine polish by hand, the particles may not break down, and may not buff out to give you the shine you are looking for. Same way, if you use a hand polish with a buffer, the particles may break down too easily and you will not get the cutting action.

the polishes are scaled on a grade of 0 to 1, 0 being non abrasive polish and 10 being the most abrasive. Most good polish compound use a mix of silica and aluminium oxide - they are hard materials and the kinetic energy during the polish action makes them abrasive.

For our general use, we do not need to go beyond 4. 1 is a Pre-wax cleaner polish, 2 is final finish polish, 3 is final cut compound, and 4 is heavy cut compound.

Polishes beyond scale 4 are generally called grit sanding materials, and we usually do not need so heavy stuff to work on our paint.

the new advancements in technology have helped many brands to manufacture what generically referred as single polish or single liquid polishing system. These are made with the help of advanced micro-abrasives and can be used for cut, polish and finish, depending on the buffing pads or materials used.

Dummies guide to car detailing - Part 2

surface preparation \ pre-wax cleaning

From the moment your car leaves the paint booth, the car surface gets affected by the pollution.

When the car leaves the paint booth, the paint is at its impenetrable best. It is like a smooth sheet without any pores. As the time goes by, the pollution in air, the regular contamination the car come across in daily life, daily wash with hard water etc open up micro pores on the paint and these contamination gets deposited and some times, a mild oxidation layer gets formed. Most of the times, a regular was is not enough to remove these contamination.

Before we start steps to enhance the shine of car paint, we need to clean the surface first. The cleaner the surface, the better the results are.

Usually paint cleaners are mildly abrasive in nature. The locally available rubbing compounds are a kind of paint cleaners, but personally, I prefer to call them paint killers.

It is very important to clean the paint from all the bonded surface contamination, oxidation layer, surface imperfections,stains,soot etc and a paint cleaner is one way of doing it, if the contamination level is high. How ever, please do keep in mind that the paint cleaner is abrasive in nature and should be used very carefully and sparingly.

If surface contamination is not much, but you feel that car already have wax coating, use good Pre-wax cleaners to strip off all the wax.

If the surface imperfection is not much, use clay bar to clean the surface. Clay bar is neither a substitute for any process nor a one-in-all solution for polishing\waxing. Clay bar is a tool which helps you to remove surface contamination easily and quickly.

It is not at all abrasive and is one of the most preferred method to condition the paint surface.

Let us Clay

Clay bar is a rectangular shaped bar, and is used after lubing it.

Clay is useful to remove metal contamination, paint contamination, soot, embedded micro contamination in the pores and is a very good glass cleaner.

How does the clay cleans the paint?

Now, that is an interesting question. Clay is an abrasive cleaner - but used properly, it is not abrasive to the car paint, but to the contamination. That is why we need to lube the clay before we apply it.

How do you know when it is time to clay your car?

Claying is preferred once or twice a year, unless the car gathers heavy contamination. Once you wash the car, gently slide your hand over the surface - if it is smooth, you are done - no need to do any thing further. If you feel teh surface is rough,grainy or bumpy, clay it.

Apply the lube and gently rub the paint using clay. Do not use much force - clay cleans the contamination by aberration, so you do not want it to do the same on your paint surface. Once the claying is done, you can see a thin film of dirt of it - you will not see dirt particles. that is because clay do not magically lift off the contamination, but cleans it by grinding it mildly.

Remember - Paint cleaners and clay are not your every month cleaning products. They are designed to clean aberrations and are mildly abrasive in nature. Compared to paint cleaner, we can safely say clay is not abrasive, but improper use of clay will mar the surface finish.

Pre-Wax Cleaners

Before we go to next step, let me add a bit more info on pre-wax cleaners.

Many people thinks clay bar is a replacement for pre-wax cleaners, but it is far from truth.

Clay removes surface contamination, while pre-wax cleaners strip old layers of wax, embedded stains and even gives surface a mild correction. They are a mixture of light polishing agents and cleaning solvents, but the cleaning ability is given by cleaning solvents - not by polishing agents. That is why you can use pre-wax cleaners almost monthly, with out affecting the paint thickness in a measurable level.

Claying should ideally followed by pre-wax cleaning so that the surface is ready for the next level of treatment.

I am not going deep into different kind of pre-wax cleaners.

Some points to remember:

Always work under a shade. A hot car surface is not a good place to do any detailing work.

Work on a small area, and buff off residues as you go. Pre wax cleaners usually do not need to dry before you can buff them off.

You can use micro fiber or soft cotton cloth folded like a pad to apply these pre-wax cleaners, but the best applicator is a foam applicator. Use a foam based applicator and use microfiber cloth to buff off. Do not use lot of pre-wax cleaner - a small amount is all you need.

Once you finish Paint cleaning \ claying \ Pre-wax cleaning, your paint surface should be smooth and should be clear of all contamination. Now, the car is ready for the next step.

Carburetor tuning - a detailed picture

Dont read it - it is nothing but some tech rant, which will go over your head unless you love your bike and love getting your hands dirty...

I am posting it here to preserve it.

Before I start, one word of friendly advice - more often than not, carburetor is best left untouched. If you really want to play around with your carb, make sure you have the required knowledge, and tools. Carb is a very vital part of your bike, and properly tuning it is no Childs play.

 

Unicorns use a Keihin CV carburetor - in a CV (Constant Velocity / constant vacuum) carburetor the throttle cable is linked not to the throttle slide as in a conventional carb, but it activates a butterfly valve, and when you open the throttle, the air pressure difference between the sealed chamber above the vacuum slid and inside carburetor venturi forces the slide up and down. the slide is located in front of the butterfly valve. A CV carb gives good mileage, and adjusts better to altitude changes, but the throttle response is not as fast as of a conventional carb.

In a CV carb, the amount of air is controlled by the butterfly valve and the amount of fuel is controlled by drop in pressure, and the jets.

 

In a nutshell, to tune a carburetor properly, you need most suitable main jet, proper needle height / clip position and optimum float height.

 

The carburetor has a number of different jets, passages and orifices to control the precise amount of fuel and air flow into engine. Engine idle, part throttle, full throttle and acceleration uses different passages, and are referred commonly as 'circuit'. Practically, more than one circuit will be functioning at a time.

 

the basic circuits are - choke, idle circuit, midrange/main, high-speed/power enrichment and accelerator pump. Though these circuits overlap, all of these have their primary functions.

 

Choke helps is cold start and warm up.

 

Idle circuit controls the idle speed and some low end throttle response. The main function of the idle circuit is to control the idle circuit. It is controlled by slow speed jet and air fuel mixture screw.

 

Midrange - as the throttle is progressively opened, the flow through idle circuit gets reduced. In this range, the most effective component is the jet needle. Midrange is characterized by steady throttle and light acceleration. Generally the throttle opening will be from a quarter to three quarter of the full range. If you feel your mixture is rich when you are at a quarter throttle, and as you open the throttle further, if you feel the mixture is becoming lean, then you need a jet needle with larger taper. If the feeling is the opposite, then what you need is a small taper jet needle. If the mixture is lean throughout the range, then you need to raise the jet needle by lowering the clip position, and vice versa. From the moment the throttle is opened, till you open it really wide, it is the jet need which controls the flow.

 

High-speed/power - it is controlled by main jet. A rich mixture will provide more power, and will keep the engine cool. If you have tuned your carburetor lean, then don’t ride with throttle wide open much - it is not good in long run. so, the safe practice is to install a main jet which is one size higher than the one which offers best performance - it will help the engine in long run.

 

Accelerator pump - usually, this needs no adjustment. If you feel a stumble (a temporary lean condition when you suddenly open the throttle), you can widen the gap on the pump linkage, to delay the timing.

 

The simple and best way of setting a carb is to set the different circuits with ideal conditions for their primary functions. So, set the air fuel mixture and idle jet for best idle, set the needle for cruising at a steady speed (midrange) and set the main jet for wide open throttle.

 

Remember - carburetor tuning is and art, compromising lot of experience, lot of science and a bit of black magic... :)

 

(I express my gratitude to many websites which taught me the basics of carburetor tuning.) 

DIY -1

I plan to start a DIY series for novices- something a i-love-my-hands-getting-dirty-but-how-do-i-start guy can use. I am sure there are lots of DIY guys/gals out there; so, feel free to add to what i write here from your experiences.

you are riding you bike - the scenery is perfect, and you are at peace with you - every thing is hunk dory and then snap goes the throttle cable. You stop the bike, rummage through your spare kit to realize that you don’t have a spare accelerator cable. Now, what is the next step? Hitch a ride to next town to get a mechanic? Or push it till the next town? What about riding your bike without the accelerator cable?

it is very easy. First, make the air-fuel mixture a bit rich, so that the bike starts and idles. Then hop on, pull the clutch lever and make the mixture super rich. Slot the gear to second, and slowly release the clutch so that the bike starts rolling (push the bike slowly with your legs – it will help the bike to get rolling). Once you get enough momentum, make the mixture a bit lean and slot the gear lever to third. now, just ride. keep playing with the air-fuel mixture screw and you should be able to ride to the next town without any hassle.