I use lots and lots of Anderson PowerPoles and (mostly) West Mountain Radio distribution units.  I have different color codes for different voltages -- red/black for 12v, orange/black for 24v, green/black for 5v, etc.  Primary 12 and 24 volt sources are big AGM batteries across float chargers.

On Oct 4, 2019, 2:03 AM, at 2:03 AM, Bill Dailey docdailey@gmail.com wrote:

I want to recommend Anderson Powerpoles for DC distribution too. A trillion times better than all the incompatible molexes. And those West Mountain Radio multi fused splitters are exactly what you want for splitters.

In addition to the WMR splitters, bare PCBs for building up your own are available too. There are also some nice non-Anderson DC distribution fuseblocks in the marine and automotive shops.

Black and red is the ham convention for 12V. If you want to run +5 or -48 (ex-telco equipment) around, you could adopt a different color convention and/or Polarizing pins conventions.

Tim N3QE

On 10/3/19 6:58 PM, Bill Dailey wrote:

There's a variety of things out there with PowerPole connectors of
varying sophistication.  You might check West Mountain Radio or
PowerWerx. Or the amateur radio community in general - someone has
probably published a dual row PCB design if you want to fab it yourself.

there's also power distribution strips that have rows of banana
jacks/binding posts with the standard 3/4" spacing to mate with dual
banana plugs

At work, pretty much everything prototype-like uses stackable double
banana plugs, usually with a reverse biased diode across the terminals
(so if you plug it in backwards, the power supply current limits or
folds back). We use a lot of coax to dual banana adapters (just because
nobody makes twisted pair banana jack to plug as an off the shelf item).

Hi I am standardising on 4 pin XLR connectors for 12 Volts as used in the TV
industry Perhaps you could use the 6 pin for 5 volts
I do not recommend the 2 pin as this is for 240 V ac
Or the 3 pin as you could take out a microphone

I am going to be Using military connectors for 24 V DC and 400 Hz

-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@lists.febo.com] On Behalf Of John
Ackermann. N8UR
Sent: 04 October 2019 12:40
To: David Van Horn via time-nuts
Subject: Re: [time-nuts] DC distribution

I use lots and lots of Anderson PowerPoles and (mostly) West Mountain Radio
distribution units.  I have different color codes for different voltages --
red/black for 12v, orange/black for 24v, green/black for 5v, etc.  Primary
12 and 24 volt sources are big AGM batteries across float chargers.

On Oct 4, 2019, 2:03 AM, at 2:03 AM, Bill Dailey docdailey@gmail.com
wrote:

time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
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No virus found in this message.
Checked by AVG - www.avg.com
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Internal Virus Database is out of date.

Yes.  I am using 12v agm.  Good wmr for the connectors also?

Bill Dailey

Negativity always wins the short game. But positivity wins the long game. - Gary Vaynerchuk

Don’t be easy to understand,
Be impossible to misunderstand

• Steve Sims

Anderson Power Poles  / West Mountain Radio <— agree.  fantastic

avail 15A, 30 A, 45A, … 175A, and more

Blue Sea Systems marine products are great also

example: ammeters with shunt in positive rail

My .02

Scott W7SLS

West Mountain is a good source for all things PowerPole, but there are a bunch of other vendors as well.  And do youself a favor -- spend $30 on the three size 15/30/45 amp crimping tool.  It saves much aggravation.  But if you're using thin wire, soldering after crimping is a good precaution.

On Oct 4, 2019, 10:03 AM, at 10:03 AM, Bill Dailey docdailey@gmail.com wrote:

On Fri, Oct 4, 2019 at 2:01 PM John Ackermann. N8UR jra@febo.com wrote:

Our club has this tool and I approve this message!

Interestingly, there is a subset of the model railroading community
that builds modular layouts.  The N-scale group (N-Trak) has adopted
Power-Poles as their standard after decades of using Cinch connectors.
PowerPoles have their limits but in these applications (time nuttery,
amateur radio, model railroads) they are pretty darn convenient.  And
a crimper makes it more so.

I also have the little pick tool that Anderson sells that makes it
easy to "convince" reluctant contacts to seat properly in the plastic
shell and make it easier to remove the contact if you need to.  Saves
wear on my "jewelers screwdrivers".

--
Peter Laws | N5UWY | plaws plaws net | Travel by Train!

With audio signals, a soldered crimp is one of the worst possible
connections. I wouldn't think it would be different for anything else,
but may go undetected until failure. If you've used the correct size of
crimp and used a proper crimping tool, then you've got the proper
pressure for a solid reliable connection. If you then solder, the heat
expands the crimp lessening the crimp pressure, and when it cools it's
no longer at the correct crimp pressure (often the wire will pull right
out), and with iffy wicking of solder. The worst of both methods
combined in one.

Where the wire is too thin for the crimp I have available, I've cut a
piece of a correct thickness wire/cable, inserted that into the crimp
along with the signal wire/cable, so it's crimped between them. I don't
know if that is the best way of handling that, but it's worked for me.

On 04/10/2019 11:41 AM, John Ackermann. N8UR wrote:

Good advice.  Another way is to put in an extra wire (or fold over the thin wire) so as to “fill up” the power pole before you crimp it.

Scott
W7SLS

That's what I do too. I do use Power Pole for my ham stuff that draws high
current but for all the <2A 12V stuff the 5.1mm barrel connector with
positive center is hard to beat because I have so many power sources and
equipment already wired for it. I am not ready to rewire all the off the
shelf equipment that came with one of those.

Power Pole are convenient for batteries though because you can use the
connector to charge the battery or use it as a source.

Didier KO4BB

On Fri, Oct 4, 2019, 2:01 PM Taka Kamiya via time-nuts <
time-nuts@lists.febo.com> wrote:

In message 119811778.3750152.1570204871728@mail.yahoo.com, Taka Kamiya via ti
me-nuts writes:

Yes, I forgot to mention that too:

I have very few 5V devices, but I power them all using USB cables
and an "Industrial[1] USB Hub" which takes 10-30V input power.

As long as you don't plug the hub's upstream ("B") port into a
computer the noise-level seems fine.

Poul-Henning

[1]  = Metal case with mounting holes instead of oddly shaped plastic

--
Poul-Henning Kamp      | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG        | TCP/IP since RFC 956
FreeBSD committer      | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.

Perhaps piling on, but be sure to adopt the “ARES standard” (same as rig runner) for your 12 v power poles ( so you don’t blow up your or their equipment, when a friend visits

S

Sent from my iPhone

In message 5D979AC0.80304@rogers.com, MLewis writes:

Dabbling in audio-homoepathy are we ?

No, don't bother responding unless you have a reference to peer-reviewed
scientific documentation for you claim.

--
Poul-Henning Kamp      | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG        | TCP/IP since RFC 956
FreeBSD committer      | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.

On 10/4/19 8:41 AM, John Ackermann.  N8UR wrote:

+++10 -- the right crimping tool is a godsend.  There's also a little
tool that helps remove the contact.

https://powerwerx.com/ is another source that's done well for me.. Lots
of inexpensive distribution stuff without fancyness (basically big
clusters of connectors).

They also have watt/current/voltage meters that plug-in inline that
handle a wide range of voltages (5-60V). however "Only current from
source to load can be measured. Drawing current in reverse will cause
damage to the meter."

They also sell the west mountain gear.

It saves much aggravation.  But if you're using thin wire, soldering
after crimping is a good precaution.

On 10/4/19 12:17 PM, MLewis wrote:

I agree on not soldering - soldering makes for a stress concentration at
the end of the strands.  With a crimped connector, wiggling the wire
bends all the strands differently. And the solder does change the
"springyness" of the crimping.

With the right crimp tool, and the willingness to throw away marginal
crimps.

If you were to pot the wire into the connector, that would probably
solve the brittle solder problem. But that's yet another assembly step
to squirt the epoxy in.

The idea of using a short piece of thicker wire is a good one.  Thanks
for that!

On 10/4/19 3:17 PM, MLewis wrote:

I used to use power pole, too but they don't lock firmly enough for my liking.  So I don't use them anymore.  It would be perfect if there is an option to add positive locking mechanism of some kind.

(Mr.) Taka Kamiya
KB4EMF / ex JF2DKG

On Friday, October 4, 2019, 4:06:50 PM EDT, Didier Juges <shalimr9@gmail.com> wrote:  

That's what I do too. I do use Power Pole for my ham stuff that draws high
current but for all the <2A 12V stuff the 5.1mm barrel connector with
positive center is hard to beat because I have so many power sources and
equipment already wired for it. I am not ready to rewire all the off the
shelf equipment that came with one of those.

Power Pole are convenient for batteries though because you can use the
connector to charge the battery or use it as a source.

Didier KO4BB

On Fri, Oct 4, 2019, 2:01 PM Taka Kamiya via time-nuts <
time-nuts@lists.febo.com> wrote:

time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Thanks to all.  I know what to do now.  Appreciated. I am finally getting to the point where I can start playing again.  Work and life has been exceptionally busy.  I am excited to build a new bench right.

Anderson it is, powerwerx and or west mountain and stick to standards.  I will search for the industrial usb hub for 5V.

Bill Dailey

Negativity always wins the short game. But positivity wins the long game. - Gary Vaynerchuk

Don’t be easy to understand,
Be impossible to misunderstand

• Steve Sims

Wire Ferrules are the best way to use thin wire in a powerpole

http://www.ferrulesdirect.com/electrical/NonInsFerr2620.htm

On 10/4/2019 5:07 PM, John Ackermann N8UR wrote:

Hi where the wire is too thin for the crimp

I actually strip the wire to long and fold it half

One reason to crimp is so there is not a hard line for a fracture
IE a point for the cable to brake
By soldering the joint you actually introduce a potential fracture point

It's all my time playing with aircraft and destructive testing
Sorry it was suppose to be non destructive testing but things brake at times

Paul

-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@lists.febo.com] On Behalf Of John
Ackermann N8UR
Sent: 04 October 2019 22:08
To: time-nuts@lists.febo.com
Subject: Re: [time-nuts] DC distribution

The idea of using a short piece of thicker wire is a good one.  Thanks
for that!

On 10/4/19 3:17 PM, MLewis wrote:

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and follow the instructions there.

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.8048 / Virus Database: 4793/15886 - Release Date: 08/14/18
Internal Virus Database is out of date.

Long ago and far away, I did read that a large(60% or so) of failures in
ww2 style equipment was due to wire breakage right at the terminal, that
is solder wicking into stranded wire. The very careful wire wrap through
holes or around terminals did nothing.  Power pole connectors do not
have crimped insulation. Spade lug and rings very often do. Strain
relief is a must, especially in presence of higher frequecy vibration.
These facts are around, just cannot recall where.
Don

On 2019-10-04 14:41, Poul-Henning Kamp wrote:

--
Dr. Don Latham  AJ7LL
PO Box 404, Frenchtown, MT, 59834
VOX: 406-626-4304

It works, but note that folding the conductor over to fill the crimp
fails NASA's workmanship standards. I'd expect that trick with the
thicker wire would too.

On 04/10/2019 5:07 PM, John Ackermann N8UR wrote:

Many ways to lock them

Insert a small 3”? tie wrap from one hole to the other, or use those twist ties that usb and power cables ship with, or use the locking mechanisms from WMR, and/or ...

Good luck whatever you decide is right for your situation

Scott

Sent from my iPhone

There are locks you can get.  I saw them on Mountain West today.

Bill Dailey

Negativity always wins the short game. But positivity wins the long game. - Gary Vaynerchuk

Don’t be easy to understand,
Be impossible to misunderstand

• Steve Sims

+1 for powerpole connectors and purchasing a proper ratcheting crimper for the powerpoles.  AND being willing to discard marginal crimps.

Content by Scott
Typos by Siri

On Oct 4, 2019, at 5:38 PM, Bill Dailey docdailey@gmail.com wrote:

There are locks you can get.  I saw them on Mountain West today.

Bill Dailey

Negativity always wins the short game. But positivity wins the long game. - Gary Vaynerchuk

Don’t be easy to understand,
Be impossible to misunderstand

• Steve Sims

time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Not a perfect solution, but for semi-permanent connections you can run a small tie-wrap lengthwise so the ends pass through the space between where the wires on each end split and the body.  Cinch it tight and the connectors won't come apart without cutting the tie wrap.

On Oct 4, 2019, 7:04 PM, at 7:04 PM, Taka Kamiya via time-nuts time-nuts@lists.febo.com wrote:

I used powerpoles on a project and tried to use a crimping tool I had to
hand. Amphenol, I think. It appeared to be the right size but ended up
bending the terminal badly where it changes from circular to flat. The
results were unreliable and I ended up soldering (though adding sleeving,
which together with the natural bend-restriction on the shell has mostly
avoided stiffening the wire where it's most vulnerable).

I know some crimp terminal are very fussy about the tool used but it's
usually the miniature ones like JST. Does the powerpole terminal need a
powerpole-specific crimp tool ? I note that the West Mountain tool seems to
be branded by themselves rather than Anderson, but I can't tell if it's
generic or made to their specs.

On Sat, Oct 5, 2019 at 2:00 AM John Ackermann N8UR jra@febo.com wrote:

On 10/4/19 1:41 PM, Poul-Henning Kamp wrote:

well..
https://nepp.nasa.gov/files/27631/NSTD87394A.pdf

doesn't give why, and doesn't explicitly say "don't crimp and solder"
but does basically say "crimp crimp connectors and solder solder connectors"

TE "Crimp Theory Fundamentals; Advanced" - explanation of what makes a
good crimp, doesn't discuss solder
https://www.youtube.com/watch?v=bAO9eCS65jw

There are actually splices designed to be crimped and soldered - but I
suspect their applicability is for specific applications.

On Monday, I will try to find one of the connector reliability people
for some references.  One challenge is that these practices ("don't
solder crimped connectors") have been around for a long time (at least
70 years), so there may not be recent published information on it.
(recent papers I found on solder joint reliability are all about PWB
connections - esp BGA, CGA, etc.)

And, to be honest, materials have changed.

There is great resistance to changing any assembly and workmanship
standard - nobody wants to be the person who says "we don't need to do
that anymore" and then a disaster happens, and one of the potential
causes is "you didn't do that"

It is entirely possible that the original rationale and explanation is
no longer valid.

There is no question that in a vibration environment, solder is
deprecated (it's hard, brittle, work hardens, etc), not to mention all
the issues with RoHS.  That said they do use solder joints in high
reliability systems - just with attention to the support of the wire.

https://www.tandfonline.com/doi/full/10.1080/14686996.2019.1640072
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100029736.pdf

In message 9e07d884-3d64-1b3a-f753-233cac34710d@earthlink.net, jimlux writes:

But it doesn't say anything about "with audio signals" at all,
which is the part that triggers my bullshit filter...

--
Poul-Henning Kamp      | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG        | TCP/IP since RFC 956
FreeBSD committer      | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.

One thing the PowerPole tool does is provide a little cavity for the
blade to go, so it keeps the depth of the crimp and also the angle where
they should be.

On 10/5/19 7:24 AM, Adrian Godwin wrote:

The Tri-Crimp (purchased from WMR of Powerwerx) has worked for me for hundreds of crimps (of the 15-30-45 amp power poles)

The WMR crimper for AWG 6 and 8 works well for the 75 A connectors

Crimping the larger (e.g. 175 Amp) Power Poles is “interesting”, in that readily available (sub US$ 150) crimpers seem to be metric.  Sometimes it takes a couple of crimps with different dies (sizes) to get it right

Good luck
S

Sent from my iPhone

On 10/4/2019 12:17 PM, MLewis wrote:

 Please explain.

I seem to recall being involved in a project where a PEng called for certain connectors to be soldered and crimped.  I expect there were specific reasons why that was specified for that particular project.  My memory is a bit hazy about the specific details of the connectors.

Re power poles..  I'm not a huge fan of them for my hobby used but I seem to recall commenting re this a few years ago and won't take up any more bandwidth re this.  I do own some equipment that uses them, and  a number of friends of mine seem quite happy with them for amateur radio use.

All the best
Mark S

mark@alignedsolutions.com
604 762 4099

A solid crimp is, I believe, generally held to be more than a solder joint
but this is in no way specific to audio cables.

On Saturday, October 5, 2019, jimlux jimlux@earthlink.net wrote:

--
Homo sum humani a me nihil alienum puto.

Hi

The biggest “issue” I’ve seen with Power Poles is that after being mated for 20 to 30
years they start to loose the spring force that holds them together.

Bob

The bulk of my wiring experience is with residential electrical (VAC)
and audio signal cables & speaker cables, with some VDC in amplifiers.
Most of the computer cables I needed I could order, so I wasn't usually
terminating them myself.

With audio, it's pretty straight forward. A number of people figure
they'll save some money and avoid the snake-oil cable sellers and make
their own cables. So they buy the materials that others have found work
well, they'd make some cables, and report they don't sound good. The
sound simply isn't clear. Many don't seem to be able to make a quality
solder joint. When they get their friend who knows how to solder to redo
the connections, and the sound is clear. Others get steered to the
crimping connectors, but use pliers or cheap crimping tools. Again,
despite quality materials, not a clear sound. They're just not a quality
connection. So they can learn to solder properly, and be at risk of the
typical stress failures of soldered connections, or the more robust and
much easier to learn path, buy a proper quality crimping tool and learn
to use it. Great connection and repeatable.

Then there's the soldered crimp. It's astounding the number of times
such a connection fails and the wire: moves back and forth, turns in
place or pulls out. The heat from soldering expands the crimp, lowering
its crimping pressure, for a poor crimp connection, but it's still tight
enough while heated that the solder can't wick in. You end up with the
combination of a poor crimp connection and a poor solder connection. I'd
guess that with a poor enough crimping, there could be enough space to
wick solder in...

An engineer told me what was up, and I cut open some connections that
seemed solid to check. In each case there was a gob of solder at the
end, but only some trace solder within the first part of the strands,
with minimal contact between the wire and the crimp. I've cut one open a
number of times over the years since, to show such to people. (Note:
NASA will not accept crimped connections of tinned stranded or tinned
solid wire. I've no idea why, but I figure it's a given that they know a
lot more about terminations and connections than I ever will.)

So my first-hand personal experience is that I've seen dozens upon
dozens of examples over four+ decades where an audio cable terminated
with soldered crimps that did not sound clear, but replacing the
terminations with properly soldered or properly crimped connections and
the sound was then clear. Not a subtle difference, but at minimum a
strong improvement, and usually a night and day difference. Now for
quality consistency, I only use crimps for audio connections and choose
connectors accordingly.

I've heard a lot of speculation over the years as to why this difference
in clarity, but nothing that seems completely credible. The closest to
credible speculation I've heard is:

• a poor connection results in multiple signal paths resulting in a
  sightly overlapped signal so the signal is no longer clear, or
• a poor connection has multiple connections and combined with eddy
  currents in the connector you can get tiny RC paths instead of a single
  long connection, so you've got multiple re-injections of a delayed
  signal that smooths tiny changes in voltage, which is your signal.
  Causation is clear. The explanation? No idea.

I've heard people say that all this analogue cable stuff doesn't matter
for digital signals because it's digital. Except that if one reads the
specs, the "digital" signal is really an digitally encoded analogue
signal. Back in the main-frame era, a number of times I was able to
correct throughput degradation or outright failure by addressing cable
issues (poor connections, shielding grounding, co-located cables of
identical length so they're sometimes surprisingly effective as
sending/receiving antennas, etc.) that techs thought would only apply in
analogue signals.

So where someone is transferring a timing signal down a cable, depending
on the frequency a quality termination/connection may be important, not
only to the longevity of the cable, but to the quality of the signal,
hence the ease, speed or consistency with which it drives and triggers
what is reading it.

And for power connections, you don't want to hope you detect the signs
of a failing loose connection due to heat, arc smells, etc. (like the
mushroom-cap screw heads on terminations for containment & detection),
before it outright fails, nor a conductor that comes free if the
wire-to-solder connection breaks. The welded connection is new to me,
but sounds like it could befit in some applications. If you've enough
power and the connection is not tight, I have seem some conductors weld
themselves to a terminal, often with a thin connection; but usually it's
material gets blown away and the conductor is now loose. Lithium battery
packs can deliver some surprising current.

So again, I don't think doing a proper (or poor) crimp connection, then
expanding it with heat to try and wick some solder into gaps that would
have been reduced by crimping and then with heating, is a very good way
to go, along with taking on the risk of the stress failures of soldered
wires.

On 05/10/2019 2:10 PM, Wes wrote:

As to crimping tools it’s important to use the correct power pole tooling as the alignment of the crimp is critical to contact insertion.

Ive found the West Mountain Radio tool to be good for the smaller powerpoles  I’ve got the Anderson crimper for the 75 amp powerpoles.

Anything larger - i use a local assembly house which has hydraulic crimpers for Anderson connectors.

On Oct 5, 2019, at 7:24 AM, Adrian Godwin artgodwin@gmail.com wrote:

I used powerpoles on a project and tried to use a crimping tool I had to
hand. Amphenol, I think. It appeared to be the right size but ended up
bending the terminal badly where it changes from circular to flat. The
results were unreliable and I ended up soldering (though adding sleeving,
which together with the natural bend-restriction on the shell has mostly
avoided stiffening the wire where it's most vulnerable).

I know some crimp terminal are very fussy about the tool used but it's
usually the miniature ones like JST. Does the powerpole terminal need a
powerpole-specific crimp tool ? I note that the West Mountain tool seems to
be branded by themselves rather than Anderson, but I can't tell if it's
generic or made to their specs.

time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

For a connection that remains undisturbed for 20 to 30 years, could you get
by with no connector at all?

On Sat, Oct 5, 2019 at 6:03 PM Bob kb8tq kb8tq@n1k.org wrote:

--
Jeremy Nichols
Sent from my iPad 6.

I've used Power-Pole connectors for many years successfully and I've
always crimped them with appropriate Power-Pole crimp tools. I never,
never solder crimped connections! Heating a crimped connection to
soldering temperature will relax the crimp force in the crimp zone and,
if properly crimped, there is no gap among the wire strands for solder
to flow into. The result is always a loss of connection quality.

Stranded wire can be tinned or coated with solder by the wire
manufacturer and crimped successfully so long as the wire is
"non-fused-tin-coated." But, much stranded tinned wire is fused to
keep the strands together after removing the insulation; this type of
stranded wire should not be crimped. Much MIL Spec wire is silver
coated, inherently non-fused and crimps well.

Professionally (in both aerospace and high-rel automotive air bag
applications), I've had the "crimp zone" of very many crimped connector
contacts metallurgically mounted, cross-sectioned and examined
microscopically after polishing and etching to reveal the individual
strands even in the crimp zone. This is the ultimate method to "qualify"
a crimped connection. A "gas-tight" crimp shows under microscopic
examination no air gaps within the crimp zone--the crimped wire bundle
has gone solid and is "gas tight."

"Crimp pull force" is another, production level, crimp quality control
method but the proper method requires making numerous crimps at various
"crimp heights" (how reduced in dimension is the height of the crimp
zone) and pull force testing the resultant crimps. The requires crimping
by a machine or qualified hand crimp tool that is adjustable. The pull
force values are plotted against crimp height and the shape of the curve
examined. A crimp height resulting in a pull force just as the pull
force begins to decrease after reaching a peak value is selected. A
"looser" crimp is not "gas tight" and a "tighter" crimp reduces the
cross-section area of the wire bundle enough to weaken the crimped
connection. Crimped connections have to be crimped within a narrow zone
of compression and only the appropriate crimp tool, appropriately
calibrated, can provide this. Forget about all types of "crimp pliers;"
these are worthless tools.

Larry McDavid
40 years experience in electronic packaging and formerly engineering
manager for a well-know connector manufacturer.

On 10/5/2019 3:03 PM, MLewis wrote:

--
Best wishes,

Larry McDavid W6FUB
Anaheim, California  (SE of Los Angeles, near Disneyland)

On Sat, 5 Oct 2019 18:03:33 -0400, MLewis wrote:

Snip

The engineer failed to explain why this is an electrical problem.

(Note:

I know why....  They don't like diodes/rectifiers in connections.
Crimped connections can produce point contact junctions thru the
tinning layer resulting in rectification.

Snip

To create a multipath error of 1 electrical degree at 20KHz (inaudible) requires a path
error of about 30m.  Not going to happen in a cm connector.

No eddy currents

For R<~1ohm, C<~1pF the time constant is <~10e-12sec.  Not in the audio domain.

Not clear!

The explination:  A poor connection rectifies.  For 1% difference between forward
and reverse conduction expect to hear about 1% THD.  To make matters worse the
rectification will likely be nonlinear with current thru the connection further increasing THD.

Snip

Regards

Bill Beam
NL7F

On 5/10/19 8:17 AM, MLewis wrote:

"If you then solder, the heat expands the crimp lessening the crimp
pressure, and when it cools it's no longer at the correct crimp pressure"

Usually crimp contacts are made of copper (PowerPole certainly are). The
wire is copper. If the crimped joint is heated for soldering, both
contact and wire will expand equally (they have the same coefficient of
expansion), so crimp pressure will remain constant.

Crimping was developed to allow fast reliable joints during production
using automation or lower skilled operators. Solder can produce very
reliable joints but is time consuming and needs skilled workers.

My experience during over 40 years of mainly repair & maintenance is
that crimping is fine when the correct tooling is available and both
contacts and wire are in as new condition (that is there must be no
tarnishing or discolouration, the first NASA link from jimlux gives that
as a reason for prohibition of contacts). In low volume or one off
situations such as the OP's request, where materials might be what's on
hand and tooling is the generic type, then flowing solder into the joint
is necessary for reliability. Heatshrink sleeving applied over the joint
and extending beyond where solder may have wicked to provides good
stress relief to prevent fracture. I've never had such a joint fail
after a repair, whereas the original crimp only joint had failed.

In message 38B5000D-C878-4470-943C-089153B156D2@alignedsolutions.com, Mark Spencer writes:

I use those, they work fine.

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On 10/5/19 5:37 PM, Scott McGrath wrote:

a sort of generic question, not specifically aimed at this application

• there's a lot of specialized operations that are better left to
  someone that knows how to do it. How does one find such assembly houses?

It's not like the "yellow pages" are useful (or maybe they are, I've not
looked recently).

Some of them I could figure out - if I needed big crimp lugs on 2/0 fine
strand wire, I'd call around to welding supply places like airgas, and
ask them.  But that is specialized knowledge in itself - I happen to
know that Airgas is a welding supply place (as well as a supplier of
bottled gases).

For instance, I'm, in the background, looking for companies that are
interested in doing runs of qty:100-200 for a combined RF/digital
device, including the RF test, etc. (see recent comment about swarms of
satellites) There's plenty of board houses that will make boards (and
assemblies), but they don't necessarily have RF expertise - and they're
busy doing what they do, they aren't interested in setting up several
hundred thousand dollars worth of test equipment and training people to
use it.

So how does one find these companies?

On 10/5/19 8:16 PM, Larry McDavid wrote:

interesting...

And I assume, then, that the degree of compression (set by the dies and
their position in the crimper) is wire gauge dependent - that is, the
crimper doesn't crimp to a specific force, it crimps to a particular
mechanical dimension, so if the number and size of strands is different,
then the degree of crush is different.

That sort of makes the "crimping a tiny wire by folding it back on
itself" or "crimping a tinywire by putting it with a big wire" a tricky
operation.