Prep/Master PM200 Operating Manual page 25

the way they were designed, the diamond tool stops cutting or keeps cutting but lifespan is
reduced drastically. The best indicator that a diamond tool is operating outside its required
temperature range is when the diamond tool cannot be held in a bare hand.
9.5 Super-Abrasive Applications
When a diamond tool is used on a surface that is softer than that which it was created to cut,
the productivity will be high but so will the diamond cost per square foot.
Examples of super-abrasive applications – thin-set mortar, cementitious, or gypsum based
underlayment, epoxy coatings containing silica, soft concrete (carbonized or rain slab) and
soft natural stone such as limestone.
9.6 Recommended Speed Settings
Any given tool has a safe operating range with regard to speed. As a rule, no tool is to be run
at less than 30 Hz or more than 90 Hz. To determine the best speed, it is best to start slow
(+/-45Hz) and monitor the tools performance. For all tools listed in this guide, appropriate
speeds follow each product description.
9.7 Importance of Concrete Densifiers
Whether an unsealed concrete surface is polished or unpolished, that surface will deteriorate
if a densifier is not used. Concrete densifiers offer protection to a concrete floor by a chemical
process in which the densifier reacts with the Calcium Hydroxide (Free Lime) present in all
cured concrete.
During hydration, the process by which cement dries, the compound Calcium Hydroxide is
formed. This compound is a weak by-product of hydration and contributes nothing to the
abrasion resistance or overall strength of the concrete. This weak material can be very easily
abraded from the surface of the concrete which leads to small voids as the particles are
pulled out.
Over time, these voids collapse which make them larger and lead to dulling of the concrete
surface or in extreme cases de-lamination. The chemical densifier fills the voids with crystal
growth created by its reaction with the Calcium Hydroxide and essentially 'glues' the cement
particles together.
The result is a surface that exhibits increased abrasion resistance which prevents dusting,
de-lamination or loss of shine if polished. We think it's important to mention densifiers
here, because if a densifier is omitted from a polishing process, that surface will NOT be
permanent.
Operating Manual PM200
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