MICRO-MACHINING GETTING UP TO SPEED ON THE SMALL STUFF
Bumotec rental
wider industry what is achievable; that we
can work to an accuracy of 0.001 mm on
workpieces as small as 1.5 mm and make
use of these tiny cutters whilst still
maintaining detail.”
Parkin drew on the vast expertise from
across the AMRC to create the micromachined
portraits. “To get Her Majesty’s
face, we scanned a real coin, using a 3D
microscope that’s normally reserved for
detecting surface roughness of texture on a
material. It works by taking a series of
pictures that are then layered up to create a
3D image. We then gave that digital 3D
image to an engineer in the Design and
Prototyping Group – Valdis Krumins – who
was able to turn it into a le format I could
work with called STL, which is used in
stereolithography CAD software.
“We were able to take that STL le and
upload it into Siemens NX 12, which is a
CAD design software package. In this
environment, we were able to make a
program for the toolpaths – roughing; semiroughing;
“We require a high
degree of accuracy and
repeatability from our
toolpaths to avoid tool
failure. The software is
important, because the
dif culty with micromachining
the rst time.
“We started at 4 mm to remove the bulk
material and then went down in size. When
we got to the nishing operations with the
0.2 mm ballnose, we were doing micron
step overs, which is literally moving a micron
every time, back and forth.”
It is this high precision and ability to
achieve accuracies to one micron that is
increasingly important for modern micro,
ultra-precision and high value manufacturing,
across a broad range of applications from
automotive, aerospace and medical to
watchmaking, electronics, cryogenics and
“At a retail price
there around machine tool selection,
inspection, environmental considerations,
cutting strategies, tooling, tool run-out and
component metrology.
“The gain is that by adopting this best
practice, companies could potentially
increase productivity and manufacture in
house components that would normally be
deemed as too dif cult.”
Parkin is hoping the ‘coin’ demonstrator
will lead to further micro-machining R&D and
commercial projects for the AMRC, which is
part of the High Value Manufacturing (HVM)
Catapult network. “I just want people
to come and have a look at what
we’re doing. “At the moment,
when people come to the
AMRC, and here to Factory
of the Future, what they
see is aerospace, with
massive aerospace
components on display and
huge machines.
“I want people to think bigger
than that, by thinking smaller and walk
onto the shop oor, down to the Bumotec or
the Kern, and go ‘wow’, the AMRC can make
some really small parts. Let’s work with
them.”
Last year, Starrag UK announced a
machine rental scheme for its Bumotec
range of multi-axis mill-turn and
machining centres. The scheme allows
customers to avoid relatively high
upfront capital expenditure yet
immediately bene t from the machines’
ability to drastically reduce lead times
by completing a range of different tasks
in a single setting. The scheme applies
to the s191 and s181 Bumotec
machines.
roughing; semi- nishing; and nishing
– which is standard practice for
any high precision machining.
machining is that you can’t
hear the cutter’s health, so you
have to get the feeds and speeds right
space. That makes micro-machining
and micro-engineering big
business, with latest reports
(by IndustryARC) suggesting
a global market value of
$12.5 billion last year,
concentrated mainly in the
US and Europe.
upwards of £600,000, the
Bumotec machine is not
affordable for every SME, but what
we can do is get those best practices out
AMRC engineers Emma Parkin
and Joe Thickett show off
the tiny artworks they have
machined
32 April 2020 | www.machinery.co.uk | MachineryMagazine | @MachineryTweets
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