Anyone ever shorten their scale cables?

pontiac428 said:
They make use of DB9 connectors because they are cheap, have lapsed patents, and come in a number of formats from solder cup to quicky ribbon punch-thru jobbers.

I think 10 years ago, I would have said to solder everything, all the time. Now, I'm not so sure, crimps have so much going for them and don't break at the solder joints from movement and vibration. There is one thing to watch out for when soldering those connectors- the pin order reverses when you change the "gender" (oh jeez) of the connectors, so check twice, solder once.
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I thought the joint breakage issue was mostly due to the newer lead free solder?

Through various workshop clean outs of deceased family members and the parents of friends I have amassed enough old school. 60/40 to solder a joint from here to the moon.

M.O.O.N. That spells solder!

Yeah, the pin swap……

I had a sheet of velum with the pin outs on it for the 27 pin connectors with male/female on either side I could hold up to the light with the proper side facing me if I got confused.

I had r r/w r/b y y/b etc and the associated pins running through my dreams.
 
RaisedByWolves said:
I thought the joint breakage issue was mostly due to the newer lead free solder?
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Nah, it's because the copper strands have to move extra to make up for the stiff joint. Wires move, even if they are run well, daily temperature changes force a little movement on a glacier slow scale. Okay, glaciers move faster these days than they used to, I need a new analogy. Anyway, copper work hardens and the strands start to break eventually, leading to buggy connections. That's the theory, anyway. In reality, it's hard to tell what caused failure, things are dirty and oxidized by then. A solder joint is better than a bad crimp in some ways, so who knows.

On a solder cup DB connector, putting a zip tie around the bundle for strain relief probaby negates the weak joint argument. It isn't very strong case against solder. Good 3-layer glue lined shrink boot over solder joints does work, I've got joints in vehicle service that are ok after 20 years thanks to the shrink boot. Stuff I used to find in Army trucks with carpy black tape would turn to caca in a few months. The bottom line is I've switched to aviation/millspec type crimps and use solder less in things that see a lot of movement on my own equipment.
 
pontiac428 said:
Nah, it's because the copper strands have to move extra to make up for the stiff joint. Wires move, even if they are run well, daily temperature changes force a little movement on a glacier slow scale. Okay, glaciers move faster these days than they used to, I need a new analogy. Anyway, copper work hardens and the strands start to break eventually, leading to buggy connections. That's the theory, anyway. In reality, it's hard to tell what caused failure, things are dirty and oxidized by then. A solder joint is better than a bad crimp in some ways, so who knows.

On a solder cup DB connector, putting a zip tie around the bundle for strain relief probaby negates the weak joint argument. It isn't very strong case against solder. Good 3-layer glue lined shrink boot over solder joints does work, I've got joints in vehicle service that are ok after 20 years thanks to the shrink boot. Stuff I used to find in Army trucks with carpy black tape would turn to caca in a few months. The bottom line is I've switched to aviation/millspec type crimps and use solder less in things that see a lot of movement on my own equipment.
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I’ve argued crimped/soldered numerous times and get what you’re saying.

The big question is let solder wick up under the jacket or keep it from doing so?

In aviation it seems like they want to keep it from wicking for inspection purposes.

In other applications, boating, automotive and such people want the extra strain relief of the jacket supporting the soldered joint.

I was taught the latter but can understand the former.

Will either way ever affect me in a meaningful way in what I do?

Probably not.
 
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Probably not is probably right.

I prefer not to wick the wire, because that is precisely the region that breaks when you do. Wicking means the wire got hot, and it's the outer extent of the stiffness caused by the solder that bends and breaks the copper strands. Makes for some tight bends that don't like much movement. When wicking is only slight, the joints hold better.

Ground shorts happen in vehicles for a lot of reasons. When they do, I want the fuse to pop. If the solder joint has more resistance from losing strands, the solder can soften, melt, and come apart. I'd rather chase my faults at the fuse box than to prove wire runs with a meter, especially when it's dark and raining and the flashlight is held in my teeth. But that's just me, I've learned to think like that.

The wisdom comes from aviation. I'm not any type of aviation mechanic, but MIL-STD wiring is something I trained and worked on, got the t-shirt and the special tools. And I doubt there's anyone here who has never un-foobed another person's chitty wiring, so it's easy to appreciate.

Here's some info that makes me feel all rosy-cheeked to read:
 

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I de-soldered mine, cut the cables, then re-soldered.

Melted a little plastic in the back of the connector on a couple spots because I was too lazy to switch to a small tip, but it's pretty straight forward if you've done any electrical soldering.
 
Looking to shorten this cable, but the metal ferrule is locked tight. Any suggestions on how to remove it?

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try a heat gun. I'll bet they used loctite. If that doesn't work, cut it off right before it, and take a pair of pliers and pull it out it will unwind itself as you pull possibly breaking the connection. you may need to make a holder for it.. use that groove in the holder, and split the holder for clamping in a vise.
 
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As noted earlier. Super easy.
 
I really like that breakout connector, but I could never use it knowing it takes the same amount of time and zero cost to re-use the solder cup DB-9. It's kind of what makes them nice in the first place.
 
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