On 11/04/2010 10:32 PM, Wild_Bill wrote:
The typical sub-D contacts that I'm familiar with use a different
crimper than described, Tim.

Typical contacts for commercial grade sub-D connectors are similar to
Molex contacts, but much smaller.. but they also have two sets of tabs
that form U shapes, one where the stripped wire gets crimped, and the
second set for gripping the wire's insulation.

The cross-section of the crimp area for the wire looks like the tabs
rolled in to form someting like a 3 with a radius at the opening of the 3.
The better quality crimpers will be compound-action types with
ratcheting mechanisms to insure a full cycle, and numerous brands are
good ones.. AMP, Black Box, Sargent, etc (all made in U.S.A.).

A simple scissor-type crimp tool will likely produce inconsistent
crimps.. some may be OK, others may separate from the wire or be loosely
crimped to the wire strands.

The crimper you described is generally for (fully round) machined
contacts with heavier wall thicknesses, as used in high reliability
avionics-type or aircraft circular connectors, but also used in higher
quality sub-D connectors.
Those crimpers sorta resemble a Buchanan splice crimper with an
extension tube protruding from one side (Daniels tool, etc).
The higher quality contacts are much better quality that typical
commercial grade contacts which are stamped and formed from thin sheet
brass.

You're definitely correct about not crushing the crimp areas with an
incorrect tool, as the widening of the contact will interfere with
proper installation, and the contacts are supposed to somewhat float in
the connector bodies, but have good alignment.

For myself, soldering pre-assembled connectors is quicker than crimping,
and a proper soldering job should be more reliable than crimping for
someone that doesn't have some crimping experience, and definitely more
reliable than trying to improvise a good crimp without the proper crimp
tool.

Heh -- I was unaware of the other option, most of the time that I've
spent in the presence of crimped connections has been at an aerospace
company.

Soldering is the way to go if you don't want to sign up for proper
tools. I think if I were doing the job all day, and had the right set
up, that I'd be faster crimping than soldering. But you need all those
special tools.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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"Applied Control Theory for Embedded Systems" was written for you.
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