Ensure stone flooring shines on
April 1st 2011 Keith Robertson considers some of the challenges associated with polishing stone flooring
Not all stone will polish. Not all stone will shine. Normally, the stones
we will most likely want to polish would be marble. It is possible
to polish some limestones although in many cases coating
with an impregnator to protect is what would be expected. It is also
possible to use a high-speed rotary on a smooth honed slate tile to
produce a sheen,but as always care is needed not to create a slip hazard.
Generally, however, when we talk about polishing we are referring
to diamond or powder polishing to produce a natural and long
lasting finish. We may have heard the expression 'diamond polishing'
but do we know exactly what it is and can we do it ourselves?
Simply put, to diamond polish is to scratch the surface of the stone
with tiny diamonds. It is a process similar to sanding wood. To
remove the scratches on a floor you have to scratch them out and
then scratch out the scratches you have caused with ever-finer
diamonds until they are no longer visible to the naked eye and as
you do so the floor will become shinier.
The diamonds are imbedded in pads and come in a large range of
grits starting anywhere from thirty to sixty grit (depending on the
supplier) for grinding the surface flat right up to eight thousand grit to
produce the highest polished finish.
It is possible to purchase rotary machines specifically designed for
diamond polishing. These are usually equipped with planetary base
plates to prevent tracking marks. They are heavier than normal single
disc rotary machines and have additional weights to make them ideal
for handling the cutting or grinding of lippage from irregular
surfaces. If you are interested in levelling irregular floors or likely to
work on large areas it is certainly well worth looking at what
equipment is available and investing in whichever one you believe
most appropriate.There are also single disc hand held machines (as
with wood sanding) for finishing edges or steps.
If on the other hand you are only interested in seeking smaller jobs, it
is quite logical to use one of your existing standard rotary polishers and
purchase a plastic plate with Velcro holders to secure the diamond discs.
These discs are used in sets of usually between three and five, the
higher the number, the more likely you are to find them easier to use
and obtain good results when you first start out. There are now pads
for dry working although it is much more likely you will work wet. If
you add some stone soap to your water you will quickly produce a
nice slurry which both makes the job easier and it is claimed adds
extra life to the diamonds.
It is important to mention that after you have completed using
each grade you should thoroughly and carefully clean the floor
surface as it is all too easy to pick up a chip of stone or a loosened
diamond grain and it will mark the floor if it gets under the drive
plate. Protect the whole work area as it is quite easy to mark skirtingboards
and lower wall surfaces.
It is feasible to keep using successive grades until the required shine
is reached although it is alternatively possible to move after using the
four hundred or eight hundred grit to a honing powder and or straight
on to a polishing powder. These are powdered abrasives usually
containing superfine crystals of aluminium oxide or tin oxide.
These powders can allow you to tackle some marble maintenance
even if you don't have a full kit to diamond grind or polish. They can
be used to minimise the scratches on a floor, even removing many of
the smallest scratches and restoring the shine to the surface.
To crystallise or not to crystallise?
I hear it said,"I can get a higher shine if I crystallise marble." I don't
dispute this, but from my own experience a crystallised shine does
not last as long."Ah, but I do it every week, every two weeks or every
month" I'm told ... H'mm.
That leads to another major consideration and that is, what does the
process do to the floor and should you ever use a crystallisation process
in the first place?
Proponents of crystallisation state that the process not only brings
out the shine, but can also create a protective layer, which will reduce
scratching by hardening the surface. The chemical in the crystallising
agent certainly causes a change in the surface. It is said that the
chemical reaction changes the surface material from Calcium carbonate
to crystal carbonate. The lime present in the stone is transformed into
calcium fluoride and the micro-crystals, which are formed,adhere to the
surface of the stone causing the surface to condense and harden.
Opponents to crystallisation state that long term the stone will
probably become damaged. I just don't know whether you should take
a serious stand against crystallisation. I do know from observation that
some floors, which have been regularly crystallised, take on an unnatural
and frankly unpleasant plastic appearance or become dimpled and the
only solution then is to regrind the floor.
Personally, I mainly use diamonds to carry out full restoration including
removing lippage and also partial restoration where the surface has been
heavily scratched or taken on an unacceptable appearance. I use honing
and polishing powders to finish the job and sometimes I use them on
their own when I am employed to tidy up the floor or to remove small
scratches. There are still times when I do crystallise,when customers are
insistent that shine is the first and only priority,but I never carry out the
process week after week on the same floor.
Ah yes, and if you have done everything you can think of, including
impregnator sealing the floor, and the final result just isn't good
enough for a customer, crystallising can often save the day.
Final thought; if you are already rotary buffing marble and are having
problems bringing out a good shine, consider trying a high speed
buffing pad instead of a normal white pad. If that still doesn't give you
what you are looking for consider what we have previously mentioned
and make use of a marble polishing powder. It will take more time
and effort, but will be worth it because the result will be better.
Oh yes, don't forget that if you are sealing with an impregnator the
better quality products do last longer.
Keith Robertson is the marketing director for the NCCA (National
Carpet Cleaners Association). More articles from National Carpet Cleaners Association: | 
