An Approach to Heavy Cleaning, Usually With d-Limonene

Hello Folks,

Introduction

Modern times have introduced modern, and usually safer. cleaning methods and
potions. Immediately the word "safer" pops up, the first reaction is that this
means it's completely safe. As this missive will describe, it's all very much a
question of degree.

Another phenomenon of modern times is the seeming invention of a potion for
almost every conceivable aspect of detailing. In reality, it can be the very same
basic product given a different smell and / or colour. The impulse behind these
are clever marketers, rather than detailers, so be warned.

All I'm trying to do with this article is make you aware of the potential damage
that can be caused and how to avoid any longer-term problems. Some detailing
potions based around d-Limonene can have their place in anyone's armoury and
very useful they are too.

The Basics

I can remember an afternoon when a friend with water-spotting on his P+J came
round. We began with a simple wash, which removed a small percentage of them.
Next came a clay-cloth clean which disposed of many more. The next stage was
to locally clean with a pre-wax cleaner. This then left very few rather more
stubborn marks for which we had to resort to a mild polish.

Watching the polish see off the marks in short order, my friend exclaimed that
we should have started out with the polish. Just how wrong could he be?(!) The
very progression of cleaning processes had more than likely done most of the
work along the way, making the polishing process very much easier than it might
otherwise have been.

So, in detailing, your immediate mantra should be to always start with the least
aggressive method or technique first. This applies to every aspect, whether it's
maintenance washing at one end of the scale or scratch treatment at the other.

Your choice of APC, and the dilutions you use should also follow this mantra.
For cars of a certain age, there's one major component of APCs and many other
cleaning fluids that we need to be a bit wary of. It's called d-Limonene.

What Is d-Limonene?

d-Limonene (d-L) is a by-product of the juicing process from citrus fruits.
Its process has its own by-product, industrial molasses, which until fairly
recently was the goal. There are two grades, food grade is not of interest to
us, but the "technical grade" is.

There is a full and concise description of d-Limonene here...

It's Described as Safe, So Where Is the Concern?

The phrase "not soluble in water" is the aspect that I want to draw attention
to mostly. Another aspect of concern is its interaction with plastics and some
rubber fittings.

Without getting too technical, the only way it is soluble in water is by the
addition of other chemicals, called surfactants. These can help make water
"wetter" or they can help make solvents "miscible" (dissolvable in water).
What they cannot do is reduce the potency of the solvent. Every last particle
is still at full strength!

So, as the surfactants help the liquid reach into every tiny crevice, it then
follows that your rinsing must be absolutely thorough. Your drying must be just
as thorough. Left to its own devices, the oils from d-L can form a film under
which water can become stagnant and eventually lead to corrosion.

Quite often, you'll hear that the best way to remove wax is to use washing-up
liquids. Well, their lovely citrus smells come from the d-L content, so there is
only a half-truth in the claim. It might degrade the oils that were present, but
entirely remove it, that's doubtful.

Then you'll hear a totally contrary claim, that a citrus based cleaner is "wax
safe". Errrrr?? Now, do you see what I mean about some marketers?

When it comes to strength, it'll be traffic film removers (TFRs) and most tar
removers that contain d-Limonene at heavy concentration. Most snow-foams
contain TFR and all cleaners in this category will have clear MSDS advice that
neither the product nor its run-off must reach natural water courses or public
drains.

The stuff is lethal to worms in the soil and almost everything alive in a river.
Its progression up the food chain just makes it more concentrated than ever!

A Safer Approach

Following our mantra, the choice of cleaner we use needs to be recognised for
its potency scale. If you have an APC, then having it in several dilutions is
the best advice. Some will still be effective at 200:1 dilution. This in turn
means you've got to be wary of it at full strength, despite the marketing!

Be aware of the effects on plastics; you will need chemical resistant bottles
and spray heads. If you're working with stonger dilutions, try to limit the area
to as local as you can get it and try and trap any liquid that might stray into
hidden crevices. If you spray high concentrations eye protection is vital! I
view anything below 100:1 to be that risky.

Keep all of these cleaners well away from 1980s plastics. For cleaning of very
dirty plastics use a polymer based potion like Finish Kare #350, which you can
dilute down quite thinly for this purpose. It'll protect the plastic as it dries.

Always have an immediate source of sufficient plain water, ready to dilute any
spills and or to fully rinse your work area. At almost every dilution, protect
your hands with nitrile gloves and immediately rinse off any splashes. Keep
children away, even if the foam or suds look like good fun, they aren't!

The most important aspect after rinsing is drying. Be aware that drying is the
most risky part of any cleaning process in terms of marring. Use of a cleaning
QD or drying aid is recommended.

Conclusions

As I have gone around detailing friends' classic cars, the one statement that
has sent shivers down my spine is reference to washing up liquids. This usually
involving the cleaning of quite vulnerable parts, particularly plastics and vinyl of
a certain age. The purpose of this missive has been to demonstrate that some
of these potent cleaners do have their place in our armoury, and others
definitely do not!

The whole point of detailing as a hobby is for you to enjoy the process almost
as much as you enjoy the results. After a fair while of being led by the crowd
all because of some hype or other, I have settled on a core list of products.

I've described how I got there in another thread, but my reliance on what can be
hazardous products is minimal. I have a few in cupboard in the rare case when I
cannot find another solution. As a person with gammy hands, I can only implore
you to look after yours and the materials that they care for.

Regards,
Steve