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Started by SteamGene, February 13, 2007, 10:25:27 PM

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SteamGene

An accident caused a large USRA tender to fall from its engine.  When it did the small plug and its wires came loose.  It appears to me that the wires were not soldered together, but just held next to each other by shrink wrap. 
This does not seem to be the best way in insure solid electrical conductivity.
Gene
Chief Brass Hat
Virginia Tidewater and Piedmont Railroad
"Only coal fired steam locomotives"

Bill Baker

Maybe the NTSB should look into this.  Who was the manufacturer?
Bill

r.cprmier

Gene;
To solder in close proximity to that nylon plug wouldn't be the wisest thing I ever heard of.  I might think that they are somehow crimped.  My thought further would be that there is some sort of "molex"@ type termination on the end of that wire, and then pushed into its respective position in the plug.  Logic  tells me that the factory would tend to be more prudent than to just be casual about its workmanship as if a standard.  If it were me, I might be mightily concerned about things like reputation, suit from my customers, etc.  Take a good look at that plug-or better yet, another plug on another engine with a like connecting facility-not just similar.

Rich   
Rich

NEW YORK NEW HAVEN & HARTFORD RR. CO.
-GONE, BUT NOT FORGOTTEN!

SteamGene

Rich, I can open another one, but this one has the wires to the two prong plug joined about half way between plug and board.  There was absolutely no evidence of solder on either end of either wire.  The only connection I could see was the shrink wrap. 
Gene
Chief Brass Hat
Virginia Tidewater and Piedmont Railroad
"Only coal fired steam locomotives"

r.cprmier

Gene;
A company called "Molex" makes myriad connecing devices, of all sizes.  my guess is that the actual plug block itself-which is nylon-wouldn't have been put near soldering heat; but that the tiny connectors that would be crimp- terminated onto the ends of the conductors, are then just shoved into the connector from the wire side, and they (usually) would catch on a moulded "detent".  As far as the shrink-wrap, there wouldn't be any reason that I could think of that a mfgr would go through the trouble of doing an in-line splce that would especially have to have a shrink-wrap operation now inserted into the whole process.  To my way of thinking, there has to have been connecting pins-whether male or female-inserted onto the wires, and then "rammed" home.

A pretty fair example of what I am talking about is the M/F plug system that the auto manufacturers use on their harness terminations.

The only other thing-and this is contingent of my possibly misinterpreting what you described-would be if the wires were just "harnessed" together by some kind of shrink-wrap; and, upon the pressure of the pull, the wires just ruptured and came apart, in-line.  In short, the wires just broke upon the sudden tension of the fall, and the wrap just happened to be where it all happened.

Rich
Rich

NEW YORK NEW HAVEN & HARTFORD RR. CO.
-GONE, BUT NOT FORGOTTEN!

ddellacca

Gene,

Were the wires apparently individually shrink wrapped at the point of
joining?
If so, was there possibly a ring of solder inside the shrink wrap?

Many computer manufacturers in the past have joined wires between
connecters using what are called solder sleeves. These are made by
molding shrink wrap material over small ring of low temp solder. The wires
are inserted into the sleeve and then hot air (sufficient to melt the solder)
is passed over the shrink wrap, shrinking the wrap as well as melting the
solder.
I've made quite a number of these connections myself during field repairs.

If the two questions above can be answered yes, then your wires were
simply missed in production, somehow, and it becomes a quality control
issue.

Dick


HOplasserem80c

ok first of all (nice one you crashed a train and almost broke it) ok and lionel HO makes a special kind of conductivity tape

brad

Quote from: HOplasserem80c on February 15, 2007, 05:56:01 PM
ok first of all (nice one you crashed a train and almost broke it) ok and lionel HO makes a special kind of conductivity tape

And again I say HUH???? Do you read your posts before submitting them?

   Anyways, it seems the wires may have pulled out of their crimped connectors. Soldering is great for wires that do not move around a lot, but for wires that need to flex and move, crimping is the way to go. I recently read an article on race car wiring and they were dead set against soldering wires  to terminals and connectors as it forms a  brittle joint that can break with movement and vibration (very prevalant in race cars). Although on a MUCH smaller scale the wires in a tender/loco lash up do have to move quite a bit.
I've used solder sleeves quite a bit in repairing car wiring except in doors where I always use crimp connectors. Hope you're back on the rails soon.

brad
I drempt, I planned, I'm building

Jim Banner

Quote from: SteamGene on February 14, 2007, 05:39:24 PM
... this one has the wires to the two prong plug joined about half way between plug and board ...

Gene, the picture I am getting is of the wiring inside the tender, not between the tender and the locomotive.  If this is the case, I wonder if there was an error in manufacture, such as accidentally reversing the two wires between locomotive and tender. I further wonder if the fault was repaired by cutting the two wires, interchanging them, and splicing them back together.   Twisting bare wires together and insulating them works, for a while at least.  But as you said, not the best way to insure solid electrical conductivity.

If I am seeing this wrong, my apologies.

And Brad!  Shame on you for expecting what's his name to use a Canadian Spell Checker on his posting!  Although I must admit I suspect that there are others of our friends from south of the border that do it too.  You just can't trust anybody any more.  I mean rereading posts to check spelling and grammar is strictly a Canadian thing, isn't it?  Isn't that why they call it a Canadian Spell Checker?  ;D ;D   
Growing older is mandatory but growing up is optional.

brad

It's not the spelling so much (although it is HORRID). The posts seem to alternate between utter jibberish with no real point or regard to the topic.and somewhat clear thought.  Somewhat like me before 10am ;D :P

brad


















I drempt, I planned, I'm building

SteamGene

Let's see, to correct some errors.  No "train" broke.  Locomotive and tender were on a work bench for DCC upside down when the rolled over and headed for the floor.  I caught the locomotive but the tender separated. 
The wires in question are the two wires, power wires I believe.  They parted inside the tender and each wire was in a separate heat shrink tubing.  There was no evidence of any solder on any of the four wire ends. 
BTW, because the tender actually stopped in mid-air before separation, there was no damage to the tender when it hit the floor.

Oh, the really ironic thing about this whole thing is that the tender in question is one of the tenders swapped by the Great Eastern and the Virginia Tidewater and Piedmont.   :o
Chief Brass Hat
Virginia Tidewater and Piedmont Railroad
"Only coal fired steam locomotives"

HOplasserem80c

make sure the decoder hasn't move in the tender

ps sorry about mt typing i am a fast typer

Andy Fekete

Quote from: HOplasserem80c on February 17, 2007, 10:46:16 AM
make sure the decoder hasn't move in the tender

ps sorry about mt typing i am a fast typer
i honestly think you need to slow down because most of you posts make no sense whatsoever

you've been hit by...
you've been struck by...
a smooth criminal

Guilford Guy

Quote from: HOplasserem80c on February 15, 2007, 05:56:01 PM
ok first of all (nice one you crashed a train and almost broke it) ok and lionel HO makes a special kind of conductivity tape

Uh when did he say he crashed his train and nobody is talking about lionel?
Alex


HOplasserem80c

i am gilford guy i am talking about lionel so get used to it!!!!!!!