Contact us
You can contact us using any
of the methods below.
Unit 3 Durham Lane
Armthorpe
Doncaster
South Yorkshire DN3 3FE
England
+44 (0)1302 836010
+44 (0)1302 831555
sales@npfasteners.com
All rights reserved
© Northern Precision Ltd.
NORTHERN PRECISION LTD
Accreditations
Northern Precision Ltd operate a quality management
system in accordance with ISO 9001.
The ISO 9001 standard is recognised worldwide and
you can be assured of the benefits of working with a
certified company knowing that our management
systems are constantly assessed and improved.
Registered in England & Wales
Company number 3275391
V.A.T Registration number
GB 684 1384 17
NORTHERN PRECISION LTD
Specialist Fasteners
for Sheet Metal
+44 (0) 1302 836010
+44 (0) 1302 831555
Tel:
Fax:
sales@npfasteners.com
Quality
Service
Reliability
5.4M3
0.33
Aluminium
Steel
0.44
0.55
7.5
7.5
7.5
15.0
15.0
0.55
0.44
1350
1350
1350
1860
1860
2.85
2.85
2.85
3.95
3.95
825
1100
830
1700
1350
Aluminium
Steel
Stainless
Steel
Stainless
All performance figures are averages obtained over a range of installations and should be used as an indicator
only. Panel material, hole preparation, installation tooling and method can affect part performance. We always
recommend that you carry out your own tests in the actual application. Please call our sales team and we will be
happy to provide you with samples as well as offering technical assistance.
First punch or drill the correct size hole. Do not deburr or chamfer the hole prior to installation as this will
remove material required during the clinching process. It is preferable to install the fastener from the punch
side of the panel.
Place the fastener in the prepared hole in the panel and then locate the fastener in the anvil.
With the panel held level, apply a parallel squeezing force until the hexagon head is installed flush to the
panel surface. Do not over squeeze the fastener into the panel as this will result in panel deformation.
When installing Self-Clinching fasteners, please pay attention to the minimum hole centreline to edge and
parent material hardness limitations.
5.50 +0.8
Length of standoff
+6.35mm min.
Do not remove any extra material or
chamfer the hole as this could result in
improper installation or reduced
performance.
HRB (ROCKWELL HARDNESS B SCALE)
Ensure that you are installing into a
panel that is ductile and at or below the
published maximum recommended
hardness for the fastener.
Ensure that attention is paid to the
minimum hole centreline to edge
dimension for each fastener. Installing
too close to an edge or bend could result
in improper installation or reduced
performance. Minimum centreline to
edge dimensions shown for each
fastener apply to one edge only. If this
distance is applied on multiple sides
there will be significant panel distortion
unless the panel edges are supported
during installation.
Electro Zinc Plated Steel (ZI) parts are suitable for installation in ductile panels with a
maximum recommended hardness of 80 HRB.
300 Series Stainless Steel (A2) parts are suitable for installation in ductile panels with a
maximum recommended hardness of 70 HRB.
Aluminium (AL) parts are suitable for installation in ductile panels with a maximum
recommended hardness of 50 HRB.
Part number is made up as follows:
(Type)-(Thread code)-(Length)-(Material/Finish code)
For example:
NSOG-5.4M3-8-A2 (Thru-threaded grounding standoff-M3 thread (larger body)-8mm
long-stainless steel)
NSOG-5.4M3-12-ZI (Thru-threaded grounding standoff-M3 thread (larger body)-12mm
long-electro zinc plated steel)
NSOG-5.4M3-6-AL (Thru-threaded grounding standoff-M3 thread (larger body)-6mm
long-aluminium)
Self-Clinching Grounding Standoffs provide strong captivated reusable female threads in a spacer format in panels
as thin as 1.0mm.
Utilising a hexagon head and a special proven clinch feature, this fastener has excellent torque-out, pull-through
and push-out characteristics whilst providing a flush finish on the underside of the panel, meaning that minimal
surface finishing is required after installation.
This thru-threaded standoff is ideal for use in applications with chassis-to-ground printed circuit boards, featuring
projecting teeth that ensure strong electrical conductivity with the board’s circuitry, thereby eliminating the need for
additional loose hardware such as serrated or star washers for example.
Self-Clinching Grounding Standoffs are available in a range of thread sizes and lengths. Manufactured from electro
zinc plated carbon steel, 300 series stainless steel, aluminium and are suitable for installation in ductile panels with
a recommended maximum hardness of 80 HRB for steel parts, 70 HRB for 300 series stainless steel parts and 50
HRB for aluminium parts.
Test panel held
firmly in vice.
Applied torque
from dial measuring
torque wrench.
Flat washer
2 pitch min.
Bolt (Grade 5 min.) Ensure
full thread engagement
(min. 6 threads
recommended).
Torque-out testing of Self-Clinching Standoffs should be performed by the gradual application of torque as shown, while
the test panel is securely held in a vice. The bolt must be of a sufficient grade to resist thread stripping.
Torque must be gradually applied until failure is observed and a maximum applied torque reading is recorded. Failure
mode is the standoff turning in the panel or cam-out.
Pull-through test for Self-Clinching Standoffs should be performed by the gradual application of an axial load as
shown.
A hardened bushing with a through-hole 0.5mm greater than the diameter of the thread should be centred over
the hexagon head and inserted into the test rig lower link. A hardened bushing should be inserted into the test rig
upper link and a bolt screwed down into the standoff. An axial load is then gradually applied on a tensile testing
machine to separate the links until a failure point is reached.
Please note that the pull-through values obtained during this test do not indicate the axial strength of the threads.
Pull-through values pertain only to the amount of force required to pull the hexagon head through the panel or for
head failure.
Tensile testing rig
upper link
Tensile testing Rig
lower link
Hardened bushing
Hardened bushing.
Applied Load.
Bolt (Grade 5 min.)
Ensure full thread
engagement (min. 6
threads recommended).
Hardened bushing with
sufficient wall thickness
to withstand applied
compression load.
Head Dia.
+ 1.6mm
Test panel.
Applied Load from
compression gauge.
Compression rig base.
Push-out testing of Self-Clinching Standoffs should be performed by the gradual application of a load as shown above.
Bushing height should be sufficient to allow free downward movement of the standoff during testing. The bushing bore
must be centred on the hexagon head of the standoff.