Medical Manufacturing and Outsourcing Special Report - November 2021 - 27

grooves, slots, or internal holes can
be tedious and time consuming.
Despite the challenges, the removal
of burrs from the production process
for medical devices is an absolute must
for high-quality, precision parts. In
many ap plications, cross-drilled holes
act as conduits for fluids, lubricants,
and gases. Failing to remove burrs
can cause blockage of these critical
passages or create turbulence in
the flow. Burrs can also lead to part
misalignments, affect dimensional
tolerances, and limit the overall
efficiency of machined components.
" Eliminating burrs is critical because
if any loose material gets dislodged
during use, there can be serious
consequences, " says Janos Garaczi,
president of Delta Machine Company.
For such applications, Garaczi
selected the Flex-Hone from Los
Angeles-based Brush Research
Manufacturing (BRM). Characterized
by the small, abrasive globules that
are permanently mounted to flexible
filaments, the product is a flexible, lowcost
tool utilized for sophisticated crosshole
deburring, honing, surfacing, and
edge blending. The hones are available
in a variety of abrasive types, sizes, and
grit selections. Flexible hones are ideal
because the tools are a cost-effective
solution to smooth edges and produce a
blended radius for cross-hole deburring.
" In terms of accessibility, I haven't
found any other tools that can do
what a Flex-Hone can, whether for
multiple cross holes or internal grooves,
says Garaczi. " There is really no way
to effectively reach those areas with
any sort of other tool. Right now, we
are making more and more complex
parts, especially when it comes to
housings with ports all over the part. "
For best results for medical devices,
the deburring tool is typically rotated
into the main bore into which the cross
holes break. After a few clockwise
strokes, the tool is removed, and the
spindle reversed to rotate and stroke
the flexible hone in a counterclockwise
direction for a few more strokes. The
forward and reverse rotation creates a
symmetrical deburring pattern. Coolant
Before
After
Medical devices often have precision components that utilize through holes that must be cross-hole
deburred. (Credit: Brush Research Manufacturing)
should be used to keep metal cuttings
and deburred metal in suspension.
According to Garaczi, removing
burrs can be particularly problematic
when dealing with machined
superalloys, such as titanium, Monel,
Inconel, Incoloy, Invar, Rene, and
Hasteloy, which are some of the most
difficult materials to machine.
" The burrs are one of the biggest
problems, particularly when machining
superalloys, " says Garaczi. " Even during
'grooving,' if you cut the material from
one side, it just pushes the burr to the
edge; and if you approach it from the
other side, it just pushes it back. It
doesn't want to break off the material
cleanly. As soon as the tool gets a bit
dull it gets a lot worse. So, sharp tools
with the right geometry are key. "
Garaczi notes that the Flex-Hone is
available with a premium nickel-coated
Flexible hones enable deburring and honing
of complex parts with cross-drilled holes and
other difficult-to-access features at less cost.
(Credit: Brush Research Manufacturing)
MEDICAL MANUFACTURING AND OUTSOURCING SPECIAL REPORT
Flexible hones are ideal for cross-hole
deburring. (Credit: Brush Research
Manufacturing)
NOVEMBER 2021 27

Medical Manufacturing and Outsourcing Special Report - November 2021

Table of Contents for the Digital Edition of Medical Manufacturing and Outsourcing Special Report - November 2021