Electrical Crimp Connectors

[Highlander40]

Now I know why it costs so much to fly in space.
98 pages on soldering wires. Over 100 pages on crimping.

This is also the reason why, when my partner hears me talking to a potential customer about building parts for space flight, he says "just hang up, it's not worth it!"

[Wotname]

If your are serious about crimping (and I am ), then you use use the same manufacturer of crimp tool as the crimp itself, i.e. if using AMP crimps, use a AMP crimping tool etc and have it re-calibrated every year or so (if using say weekly).

Otherwise just use whatever takes your fancy and take your chances - if you don't want to use best practice then a simple test is to give the crimped wire a good tug!

[Maine Sail]

Originally Posted by Ziggy

Yes. You can use a "lineman splice" (google it or see the attached photos). Don't forget to put shrink tubing over the splice.

.

Ziggy,

Just as a point of clarification that the Western Union or Lineman's Splice was initially intended for solid conductor wire. NASA does not allow the use of WU splices on stranded wire and neither does the ABYC. I have personally asked John Adey, ABYC's technical director, for clarification on their definition of ""mechanical connection" and wire twisting, WU splices etc. do not meet the definition.

For those of us who still do this for a living, even when only part time, and have to put our name on our work, it is best that we wire as close to the currently available standards as possible. I am going to guess Bill T. and others do the same or similar to what I do when it comes to standards compliance,even when not required to do so on used boats. You should see the boat I am currently working on for new electronics.. Just glad I charge by the hour cause what I thought I could re-use I really can't/won't.

For DIY boat owners you can do whatever you want, ABYC standards are NOT mandatory for you, but should keep your insurance company in mind. You may also want to keep in mind re-sale or insurance surveys. Many a good surveyor will note unsafe, or what they may deem as unsafe, connections whether or not they actually are. If an insurance survey, your insurer may require the noted items be fixed or changed.

I find nothing wrong with properly done crimp and solder joints which always includes proper strain relief, the right solder, and a heat sink tor technique to prevent solder creep. The key phrase is "properly done". There are a few here that know how to do it right, but the vast majority do not, hence the ABYC guidelines around solder. I still solder PL-259 pins etc. but most everything else is crimp with factory made adhesive lined heat shrink crimp connectors, which are waterproof.

For those of use who have been on board and worked on many, many vessels it becomes quite clear why the guidelines are what they are as I am going to guess we've all seen it.

When you are a DIY with an N=1 or N=2 vessels, you may never see a problem but when you've worked on hundreds of vessels N=300, N=500 etc. it becomes apparent that the large majority of people attempting solder joints should not have and the failure rates are rather surprising, mostly from improper technique. I admit that I don't recall seeing a properly done solder joint fail, but then again I can perhaps count on one hand the number of properly done solder connections I have actually seen..

Improper technique is just as bad with crimps as it is with solder. Both methods should really be done correctly, and with the right tools, but neither is completely 100% infallible. With proper techniques and methods though you can get darn close to 100% with either method.

[Ziggy]

Originally Posted by Maine Sail

Just as a point of clarification that the Western Union or Lineman's Splice was initially intended for solid conductor wire. NASA does not allow the use of WU splices on stranded wire and neither does the ABYC. I have personally asked John Adey, ABYC's technical director, for clarification on their definition of ""mechanical connection" and wire twisting, WU splices etc. do not meet the definition.

I agree with everything you said. However, when you need to splice 20 AWG or smaller stranded wires, a soldered lineman splice covered with adhesive shrink tubing will work OK in most cases. It is important to mechanically stabilize the cable at both ends of the splice to keep it from flexing. I would use this method only with wires that are too small to crimp, or when crimping is otherwise not possible.

Also, with the right tools, crimping requires less skill to execute properly than soldering.

[DeepFrz]

I took a 3 week soldering course taught by a former employer, a "Large Scale" computer manufacturer. When I finished the course I was a marginally (my personal evaluation) good solderer. However, I would not now attempt to solder anything that could be done using a crimp on connector using the proper tools. For one thing, my hands are to shaky to ensure a good solder connection. But even if my hands didn't shake I wouldn't do it for reasons mentioned earlier in the thread.

As was previously noted, the "Linesman's splice" was meant for solid wire, which really has no place on a boat. I have joined stranded wire using the Linesman's splice and it worked. Not very pretty. I did make sure it was well supported by several shrink wrap layers and extended them well beyond the hardness of the solder joint. The adhesive type of shrink wrap is best, IMO.

[Rick]

Main Sail is correct! Wire crimp failures are due to using the wrong crimper with the terminal and/or the wrong terminal with the wire size!

If you use wrong brand terminal with a good tool you might not get a good crimp. Keep in mind that there is no valid argument for soldering in comparison with good crimping in boating applications.

Check out the following;
Improper crimping procedures eventually cause terminal failure

[GordMay]

The far right column of my Wire Sizing Chart indicates a minimum pull-out pressure for a crimp terminations.
Any termination that won’t withstand the indicated tension, is inadequate, and must be re-done.
➥ Wire Size Chart.1 - Read /w "Ohm's Law & You" Cruisers & Sailing Photo Gallery

[barnakiel]

For bilge connections (if cannot be avoided altogether) - keep them as high above the water as you can, crimp on vaseline and cover with glued shink, then paint over with the magic black goo from Starbrite (what was its name?).

If connection is permanently under water: slide a piece of pvc tube over the wires and fill it with polyurethane, slide it over the connection, leave to dry. Nearly bullet-proof (but I am not sure how good if exposed to oil).

barnie

[David M]

Originally Posted by GordMay

NASA’s Terminating Standards

Soldered ➥ http://www.hq.nasa.gov/office/codeq/doctree/NS87393.pdf

Crimped ➥ http://www.hq.nasa.gov/office/codeq/doctree/87394.pdf

Good stuff Gord. Its worth a read. But remember, spiral wrap is not allowed in your space craft or launch vehicle.

In places where you want to displace water, use silicon grease instead of Vaseline. Its best not to use petroleum based products such as Vaseline with wire insulation. In some cases, especially with rubber, Vaseline can cause insulation to swell or weaken. Vaseline also eventually washes away.

[Strygaldwir]

I was taught a long time ago, crimping is for a physical connection, soldering is for an electrical connection. Since that instruction, I have done both on all terminal connection on-board. I crimp the terminal to the wire, then solder the crimped connection, then put silicon dielectric grease on the connection followed up by heat shrinking. The heat shrinking is nowhere near hot enough, or sustained enough to cause the solder to re-flow.

Have not had a failure in that type of joint, yet. There was some discussion about whether the soldering will introduce brittleness for the length of the soldered connection. I continue to be of the opinion that the wire is stronger more flexible than the lead/tin solder and would possibly break first. I MIGHT not do it this way for a space shuttle, but, it has been very successful for me to date. i.e. no failures on any of these joints.

[goboatingnow]

When I was designing equipment for the car industry you could get fired for two things soldering crimps and using insulating tape

crimps provide a gas tight joint. Howver the junk that's out there pretending to be crimps is a joke. Do not crimp using pre insulated crimps use a proper crimp and crimp tool Nd then provide strain relief

Don't solder it weakens the connection And in large crimps it's difficult to get enough heat into the joint. People who can't crimp solder.

Dave

[thinwater]

... all threads on...

* crimp vs. solder
* anchors
* chain
* wax
* GPS
* multihull vs. half boats (could help myself)


... are intended to boost the hit count. It couldn't be anything else. Should we move these (and a few I've missed) to the "fight club"?

[Wotname]

Originally Posted by goboatingnow

..... Do not crimp using pre insulated crimps use a proper crimp and crimp tool .......

Perhaps a bit over-stated....for instance, AMP pre insulated diamond grip crimps meet the requirements of MIL-T-7928, Type II, Class 1 and 2 and are widely used in commercial, marine, aerospace and military applications.

See Ring and Spade Tongue Terminals Product Line Information - Tyco Electronics

However I agree with you in that there are plenty of very dodgy pre insulated crimps around to trap the novice.

[Maine Sail]

Originally Posted by Wotname

Perhaps a bit over-stated....for instance, AMP pre insulated diamond grip crimps meet the requirements of MIL-T-7928, Type II, Class 1 and 2 and are widely used in commercial, marine, aerospace and military applications.

See Ring and Spade Tongue Terminals Product Line Information - Tyco Electronics

However I agree with you in that there are plenty of very dodgy pre insulated crimps around to trap the novice.

I agree. I used AMP PIDG terminals for a number of years before I made the switch to heat shrink crimp. FTZ and a few other companies make terminals with the same specs as the AMP PIDG terminals that will work in the AMP T-Head crimpers to but don't expect to find them at an autoparts store or WalMart.. There are literally millions of insulated PIDG type terminals in aircraft flying passengers & cargo around the world every day...

[Chief Engineer]

After I check My GPS, I wax poetic as I let out the anchor and chain from my monohull....I keep my sidearm handy to ward off Crimps, Pirates and "soldiers".

Originally Posted by thinwater

... all threads on...

* crimp vs. solder
* anchors
* chain
* wax
* GPS
* multihull vs. half boats (could help myself)


... are intended to boost the hit count. It couldn't be anything else. Should we move these (and a few I've missed) to the "fight club"?