Tap Testing is enabling Productive Machines Optimization
Tap testing, enhanced by Productive Machines technology,
brings precision and efficiency to manufacturing. It
empowers operators to optimize machine tool performance,
reduce waste, and enhance product quality.
What is tap testing in CNC machining?
Tap testing, also known as impact testing, identifies
structural dynamics by impacting a structure and
measuring its response, in other words, tap testing
tells us how flexible a machine tool assembly is.
In CNC milling, the tip of the milling tool is excited
with a hammer to induce vibrations while collecting the
measurement with an accelerometer.
The relationship between the force (input) and
acceleration data (output) is the transfer function of
the structure which is also called Frequency Response
FRF represents the dynamic stiffness of the structure
across the frequency spectrum and is used as an input
for spindle speed calculator to calculate recommended
spindle speed and depth of cut.
How to perform a tap test?
Productive Machines has partnered with
Kistler, a lead supplier of a Tap Test equipment, to offer a
complete hardware tap test kit. We have also partnered
with Research Centres to provide tap test services or
on-site/remote training for companies unfamiliar with
the tap testing method.
What do we do with FRF data?
DigiTap, our tap test standalone software, calculates the
FRF data from the tap test. FRF data includes natural
frequencies, stiffness and damping ratios of the machine
FRF data feeds into the Spindle Speed Calculator to
generate a stability lobe diagram. The user then
knows to select a stable spindle speed and depth of cut
under the stability boundary.