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Re: solder vs crimp Re: MOT supply construction question



Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Jonathan,

Since I work in the electronics industry, I see this stuff all the time.
"Good" solder wire connections just don't fail.  If the metals are
solderable, the solder is good, and the skill is there, the connections are
fine.  Of course, the average guy off the street with a cheap soldering
iron, little skill....  mileage may vary.

Crimp connections fail about 30X more.  Bad tool, didn't insert wire far
enough, crimped on insulation, pulled loose...  A lot "happens" with crimp
connections.  Stranded wire can also move around in there and loosen things
up too (big problem with screw clamp connections).  In general, in the
industrial electronics world, I would say crimp connection failures are way
up there in the charts compared to solder wire connections.  Connections
that get moved around a lot can also fail a crimp easily.

If one crimps a connection and then goes back and flows solder into it
(kind of tricky) the connection will never fail.  I often do that on really
important connections like grounds.  The wire will tear and break long
before the connection fails there.  That is often done on test probes and
such were it gets a lot of rough use.

Cheers,
	
	Terry



At 08:43 AM 10/13/2002 -0700, you wrote:
>Jim,
>
>I have seen this debate  before, but it seems as if the discussion centers
>on solder VS crimping. What are the drawbacks of crimping AND soldering? I
>have seen solder only connections "eject" the wire, I have seen many crimp
>connectors "lose" the wire, but I have never seen a crimp and solder joint
>fail for any reason other than extreme mechanical damage or heat, which
>would have ruined things regardless of the nature of their connection.
>
>Anyway, is there a failure mode that occurs only (or more often) when
>soldered and crimped?
>
>Regards,
>
>Jonathan Peakall
>
>----- Original Message -----
>From: "Tesla list" <tesla-at-pupman-dot-com>
>To: <tesla-at-pupman-dot-com>
>Sent: Saturday, October 12, 2002 11:00 AM
>Subject: solder vs crimp Re: MOT supply construction question
>
>
>> Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>"
><jimlux-at-earthlink-dot-net>
>>
>> A couple interesting things to note about soldering vs crimping...
>>
>> crimping, properly done, produces a gas tight seal (important to prevent
>> corrosion) between the conductors as well as good mechanical connection.
>A
>> good crimped connection deforms the metal sufficiently past the yield
>point,
>> but not too much, so that the "spring back" keeps the connection secure,
>> even under thermal cycling (the coefficient of expansion of the two metals
>> might be different) and vibration. I might add that casually getting the
>$5
>> crimpers out and cranking down on the connector is probably not "properly
>> done".. you need fairly well machined tooling, the right equipment, and
>raw
>> connectors that are consistently manufactured.
>>
>> Soldering certainly does the gas tight seal (if done right), but,
>remember,
>> "solder is not structural".  It is quite brittle and work hardens.  If
>> you're in an environment that has lots of thermal cycling and/or
>vibration,
>> soldered joints are more likely to fail, unless efforts are made to remove
>> the stress from the solder joint (i.e. the wire is mechanically attached
>> some other way).  There is also a fair amount of art and science in the
>> selection of the particular solder alloy, the flux, and the cleaning
>> process.
>>
>> One certainly can't say that, universally, solder or crimp is a better way
>> to go.  One can bungle either..
>>
>> For the original question, I'd go with good quality crimp on spade lugs.
>>
>> ----- Original Message -----
>> From: "Tesla list" <tesla-at-pupman-dot-com>
>> To: <tesla-at-pupman-dot-com>
>> Sent: Friday, October 11, 2002 5:55 PM
>> Subject: Re: MOT supply construction question
>>
>>
>> > Original poster: "Jonathan Peakall by way of Terry Fritz
>> <twftesla-at-qwest-dot-net>" <jpeakall-at-madlabs.info>
>> >
>> > Mike,
>> >
>> > I should have mentioned, I crimp *and* solder. Good physical connection
>is
>> > important.
>> >
>> > Regards,
>> >
>> > Jonathan Peakall
>> >
>> > ----- Original Message -----
>> > From: "Tesla list" <tesla-at-pupman-dot-com>
>> > To: <tesla-at-pupman-dot-com>
>> > Sent: Friday, October 11, 2002 2:55 PM
>> > Subject: MOT supply construction question
>> >
>> >
>> > > Original poster: "Michael Strube by way of Terry Fritz
>> > <twftesla-at-qwest-dot-net>" <mjstrube-at-earthlink-dot-net>
>> > >
>> > >
>> > > I m in the process of constructing a MOT-based supply that will be
>> > immersed in
>> > > oil. I ve not tried this before, so here is a naïve question do the
>> > connections
>> > > that will be under oil need to be soldered? Up to this point, all my
>dry
>> > > transformers have just used the quick connects that are available on
>> MOTs.
>> > I m
>> > > guessing that I need to solder those now if they will be in oil.
>Thanks
>> in
>> > > advance for any help.
>> > >
>> > > Mike
>> > >
>> > >
>>
>>
>>
>>
>