DSCINCE….2
Proper Care of Diamond Wheels
BEFORE SHARPENING A SQUEEGEE, consider the type, age, and cleanliness of the squeegee material.
1. Identify the type of material Different squeegee blades sharpen differently. Most polyurethane, neoprene, and
rubber blades sharpen well. A few, however, are made with special formulations that impart very high abrasion
resistance. Such blades may take a long time to sharpen and overheat during the process. Others have thermo-
plastic fillers added for ease of fabrication and sharpening. These may melt at relatively low temperatures. If you
have such problems or questions about your material, please call Encore Engineering.
2. Check the age of the material. Most polyurethane squeegees last 12-14 months before their physical properties
change enough to be unusable. Even new blades that are stored for a long time will show signs of aging including:
changed durometer, lost resilience, and lowered melting point. When this happens, the squeegee will tend to melt
onto the sharpening wheel or show a fractured edge after sharpening. To test to see if the material is too old for
printing and sharpening: Put one corner of the squeegee in a vise and tighten it until the squeegee is only 1/3 of
its original thickness. Leave it for 15 seconds and then release the pressure. The material should spring back to its
original form within 15 seconds. If the squeegee does not spring back, the material is old and should not be used
for printing or sharpening.
3. Make sure the squeegee is clean, dry, solvent-, and plasticizer-free. Squeegees with wet or dry ink on them
CANNOT BE SHARPENED! Nor can squeegees that come directly off the press and are still soft or swollen
from chemicals. Squeegees must rest a minimum of 6-12 hours (preferably 12 hours) between runs and should be
sharpened AFTER the rest NOT BEFORE.
DURING SHARPENING, pay attention to the amount of material that is left on the diamond wheel and the
temperature of the wheel.
1. If a heavy residue appears on the wheel, clean the wheel immediately with Encore cleaning sticks (furnished with
your unit and may be purchased from Encore). With a good quality squeegee, the diamond wheel should be free
of heavy deposits. The slight residue on the surface can be cleaned periodically (between 5-10 cycles).
2. While it is normal for the wheel to heat up during sharpening, it should not run hotter than 140-170° F (which is
far below the melting point of quality squeegee material). If you see any signs of melting, check both the wheel
temperature and the quality of the squeegee material. There are 3 reasons for the wheel to get hotter that 170° F:
a. If the wheel is not cleaned regularly, the squeegee shavings will "bake" onto the wheel’s surface will
generate extra frictional heat, which only coats the wheel further. Eventually, the wheel loses its grinding ability
because the diamonds are coated with baked plastic. Note: If your Kut/Kutronic series sharpener does not have an
access hole in the wheel housing for cleaning the wheel, upgrade by ordering DWC-KIT from Encore.
b. If the squeegee is not clean and solvent-free, it will hasten the particle deposit and baking process and will
leave an UNREMOVABLE ring on the wheel. Inked or solvent-laden squeegees can ruin a new wheel within the
first hour of use, especially if the wheel has a fine grit surface (e.g. 230-360).
c. If the wheel remains clean yet still heats up, chances are you are sharpening an abrasion-resistant
material that is not designed to be sharpened with abrasive wheels. If you use such material, call Encore
Engineering and we will advise you on your options.
d. If the wheel is being used continuously it may not have a chance to cool down, especially if the sharpening
unit has no vacuum. During continuous use, allow 2 minutes of cool down time between squeegees. Let the
grinding motor run during this time (on automatic equipment, set the transport motor speed to “0” while the
grinding motor is running).
AFTER SHARPENING always clean the wheel thoroughly, using a cleaning stick, and examine it for baked-on
deposits. If residue on the wheel resists the cleaning stick try to clean the affected areas with a strong paint remover
(polyurethane paint remover if possible). Remove the wheel from the machine, brush on the paint remover allowing
the residue to soften. Use a medium-stiff steel brush remove the residue, then rinse off the paint-remover and allow
the wheel to dry. Rub the diamond surface clean with the Cleaning Sticks. Note: 6” wheels are coated with high-temp
black paint to enhance heat dissipation. If the black paint -- on all-steel wheels -- is removed during cleaning, recoat
the wheel with a high –temp black paint, such as Rustoleum 7778 black. Make sure to mask off the diamond surface
during painting.)
