Power Floating Technique

A power float is a
concrete finishing machine designed to smooth and to
some degree level the surface of the concrete to an
exceptionally high tolerance.
For the best results a
power float, can finish your concrete to an
exceptionally flat, hard and durable surface.
Slight low and high spots
can be levelled by the operation of the float, but the
concrete should be laid, levelled and compacted using
vibration before a float is used. The vibration provides
removal of air, which is essential for concrete to
achieve full strength and therefore durability.
Power float Options
A key requirement for a
power float is its ability to operate reliably and be
perfectly balanced. Powerfloats provide a simple
method of ensuring that the blades are level and a quick
and easy method of adjustment if they become out of
line. Floats with poorly aligned blades become unstable,
and will make it impossible for the operator to achieve
a high tolerance finish.
Our Power floats are
available as either petrol or the new diesel option.
Engine options vary depending on the size of the float
and fuel option. Typically engine sizes vary between
5-10 HP for pedestrian floats to 20-25HP for the larger
ride on models.
Floats are available in
various sizes. The most popular sizes are:
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diameter
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suitable for
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24” / 0.6 mtr
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Edging float used for working through tight
areas i.e. doorways in finished buildings
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36” / 09 mtr
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Standard float used in typical applications
such as factories, warehouses, airport
hangars, etc
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46” / 1.2 mtr
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large floor areas such as warehouses where
high quality finish is required
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BS and European safety
standards are becoming ever tighter and regulate a
multitude of features available on the float. Triple
guard rings, engine cutout switches, and electrical
protection are fitted as standard and
Speedcrete are committed in providing safe and reliable
machines.
Blade Selection
Floats can be fitted with
a variety of blades or pans depending upon the
application.
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Floating:
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float blades
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used first for floating
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float pan
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alternative to float blades
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Finishing:
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finish blades
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used for two or more passes for final finish
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Combined:
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combination blades
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one side used for floating, the other side
for finishing
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Typically, a
pan is used
as this simply locks under the finish blades and then is
removed for final floating.
Combination blades are
normally only used on small contracts where a high
quality finish is required but not ‘super flat’ finish
would be needed. Using two types of blade usually ends
up cheaper.
Timing & Methods
It is essential that the
floating is started at the correct time. The operator
must wait until the concrete is hard enough to hold the
weight of the float and the operator.
A useful mark when
considering when to begin is when the operator leaves
about 3mm footprints when standing upon the surface.
This is because if the concrete is too wet the machine
will simply tear up the surface and indeed if it is too
dry the machine will not be able to trim high spots and
fill lows effectively.
As discussed in the blade
choice there are typically two stages to a complete job.
Stage 1: Floating
The float is
fitted with either float blades or a float pan. In the
example below floating starts at the top of the slab and
moves top to bottom. The operator walks backwards and
thus the float removes any footprints of the operator.
The slab should be given an initial pass and the speed
should be consistent and slow.
The float blades for this
stage should be flat to create suction between float
blade and concrete surface. At this stage circular marks
will be left on the surface. These should not be light
marks, and will be removed on the second stage. The
float should pass over any form work in place to ensure level
joints.
Stage 2: Finishing
Once the surface
has been 'floated', the blades of the float are changed
or the floating pan is simply removed to reveal the
finishing blades. The finishing stage should be started
when the surface has dried, and walking over the surface
leaves no indents. A good gauge is when the operator can
place his hand on the concrete surface and cement is not
left on his hand.
For the finishing pass the
blades are angled to suit the concrete, increasing the
angle after each pass - an angle of around 5-10º is
usual, the steeper the angle the harder the finish.
Several passes with the finish blades may be required to
achieve the specified finish.
Caution!
Extreme care must be taken
at both stages of floating to ensure that all areas of
the concrete are covered by the float. In most cases
hand floating the edges, joints around obstructions and
at walls should be done prior to floating. Speedcrete
provides a variety of tools for this purpose. This
ensures that no large high spots are evident as the power
float will not take off excessively large high points is the bay.
Where tolerance is
critical, either our lightweight or heavy duty
Bumpcutter should be passed over the surface to trim
high spots and to aid quicker completion of the job.
A warmish dry day with slight wind yields an ideal
curing environment. As you are probably aware a cold wet
day is not recommended for laying concrete but sometimes
unavoidable!
There is no substitute for
good quality concrete, care in preparing the formwork,
correct compaction, initial levelling and care and
patience in the final finishing of all the surface area.
Please browse our products
section for details of tools that perform these jobs.
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