Silicone Helps Earplug Redesign
Engineers at McKeon Products Inc., Warren Mich., came up with a new design and 16-cavity slide mold that would let them manufacture silicone earplugs for swimmers.
Unfortunately, the mold
has significant undercuts,
making it difficult
to remove plugs
from the mold without
tearing them and
leaving pieces stuck in
the mold. And the mold’s
surface would get so dirty
with silicone, the mold had
to be removed every two
weeks for 8 hr of cleaning.
To avoid an expensive redesign of the tool, the
company used the KE2004-20 Series of silicones from
Shin-Etsu Silicones of America, Akron, Ohio, which
are said to have the highest tear strength of any silicone
on the market. The new silicone also has good release
properties, so earplugs could be removed from the mold
without tearing and still have a soft feel. Other benefits
include less maintenance on the mold tool and a 60%
drop in scrap, which explains a 100% improvement in
productivity.
McKeon invented silicone earplugs for swimmers in
1962. Mack’s Pillow Soft silicone earplugs have been a
top seller ever since.