Would you trust Crimp Connectors

For mains connections?

I have some nice insulated 1/4" blade type crimp connectors. Even though I can get a heckuva good crimp on them, some little part of me feels like I should solder these guys. That would mean getting non-insulated ones, soldering them, and then using heat-shrink over them. Or, just soldering the wires directly to the terminals and be done with the quick connects. I just like the idea of being able to easily plug/unplug things for maintenance, etc.

What do you think?

can you add heatshrink afterwards?

i dont. especially not for anything critical as they are often a more resistive connection.
and not where safety is concerned, earth wires etc.

also not on speakers, this could be especially bad news if they fail when to be used with your valve amps

A good gas tight crimp should be as good as solder. A bad crimp is as bad as bad solder.

JR

Thanks guys; good points all.

Yes I could add heatshrink; in fact I can get non-insulated versions, crimp AND solder the wires to them, and heatshrink them after...this may be what I'll do.

Thanks for your perspectives,

Mike

What John says.

A _controlled_ crimp is an incredibly good joint. 400-Ampere and larger feeder cables are often terminated with a hydraulic press, with proper dies and lugs for the wire used.

At this power level, solder is "dangerous" because in a fault it will melt and spray sooner than copper.

I have a suspicion that the chassis ground wire must NOT be a solder joint, or at least not ONLY a solder-joint, for this reason. I always see a crimp lug, possibly because solder could let-go just when you need it most. A crimp lug can carry about 4 times the energy before it blows.

The usual hand-crimper (without full-cycle lock) in the wrong hands, or the wrong crimps for the wire, is as bad as any other bad connection.

Billions of contacts large and small are crimped, and very few fail.

IMHO, there are better connectors than 1/4" blade. They have worked OK for 60+ years, true, but I've also seen a fair share fail to hold the blade well. If you are using legacy parts which are supplied as 1/4" blade, OK. If you have free choice, even the awful thing used on IDE hard-drives is IMHO better.

Don't use Honda ABS/EVAC connectors (not that you would be likely to!). Twice now I have dodged $160 ABS sensor replacement by simply opening, glaring-at, and re-plugging the connector.

PRR said:

Twice now I have dodged $160 ABS sensor replacement by simply opening, glaring-at, and re-plugging the connector.

Click to expand...

I have repaired outdoors AC units and laundry dryers the same way.  Quite a few modern Ampeg amps with efx loop jacks, too. 

'clean and tight'
and some corrosion inhibiting compound
for the big crimp connections (#2awg-750mcm) I do at work.

for little diy stuff I'll tin the stranded wire before crimping the lug

shabtek said:

for little diy stuff I'll tin the stranded wire before crimping the lug

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omg. stop that right now! that's one of my biggest pet peeves..
take a tinned stranded wire and crush it with your pliers. see what you get?
pre-tinning does nothing more than include broken bits of solder inside your crimp. and solder is softer than copper, so you now have soft metal in there that will allow more movement over time.

Respectfully,
Jason

by lug I mean ring terminal or contact pin (DL, edac, molex, etc.) tin it right up to the insulation, makes for least strain. and/or add heatshrink/ expandable neoprene sleeving if there is likelihood it will wiggle loose.
and use a real ratcheting crimper if you can, for spade/ring terminals it is not too spendy, other tooling is not always in da diy budget

well, if a jobs worth doing...

Just wanted to add my distaste for Molex connectors (like the kind used for power in desktop PCs). My console is all terminated to Molex and crimping to very narrow gauge snake wire is unreliable and a pain in the ass. Crimping the connector can often cut right through the wire, and it is also easy to crimp thoroughly and still not make a solid connection. Regardless of the wire gauge, the pins are almost always ruined if you need to remove them from the housing. It works ok for larger gauge wires (<24 or so).

Best, Ben

The red -blue-yellow ring,spade,pin crimps are used extensively in all electrical industries .
Used tens of thousands when I was a control panel engineer ..and properly implemented.never fail !.
Only use a ratchet type tool....the cheap car/auto strip and crimp types are a waste of time !


http://wiki.diyfaq.org.uk/index.php?title=Cable_crimping

BTW  I dont like the BUTT type cable joints unless totally nessasary  :

plumsolly said:

Just wanted to add my distaste for Molex connectors .......  and crimping to very narrow gauge snake wire is unreliable and a pain in the ass........

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I use Molex pins at work all the time and they're great. It costs a fortune to buy all the right dies but that's the key, having the right die. We use Molex pins for DS1 drain wires on wire wrap terminals and larger Molex pins on 129VDC control systems without issue. I tried using the smaller of our crimpers on a Molex pin meant for even smaller gauge wire/pins for my Hairball Audio 1176 and got myself into trouble. The crimper must be used properly to ensure that one part of the die crimps the wire and the other part wraps the grips of the crimp around the insulation.

By the way, I work for a power company and a soldered connection is a very rare thing to see around here. Everything from 22AWG to 4/0AWG that I've worked with is crimped. Anything smaller is punched.

wow, subjective or what...
this is almost as bad as a 'which capacitor is best?' thread

I see a number of people sharing personal experience. While this may not be pure scientific method, it doesn't sound as subjective as most discussions about things audio.

A great deal of purely objective research has gone into proving the reliability of crimp connections for industry. So I trust them when done properly.

JR

hey JR, i didnt mean anything by it, dont get me wrong, much respect. and i see the benefits and arguments from both sides.
i was just making a comparison i thought was fair given the varying opinions.

as the exact parameters and conditions/use was already deviated from anyway, it just turned into lots of opinions and personal experience as you say. merely an observation.

obviously it is possible to feed enough juice through most types of terminals to melt them if you really wanted.
so again, obviously, solder may not be the best choice in high current applications so i made assumptions about the OP 'mains power' being purely what you would expect through a household socket with a fuse in series.
just learning from you, and adding my personal experience too.

although i'm not up to the level of many here, yourself included, but in my limited experience i have seen quite a few loose crimp connectors on pcbs, speaker terminals and mains connections.

the one thing i think it is fair to say about all this, is that its easy to crimp badly.
maybe even easier than to solder badly. especially with inferior tools.

I'll throw in my own experience.

Same as anything else. If not done properly it is as bad as a bad solder. As said, having the right tool is the key. However, even if you  have an average tool it still can be reliably executed.

Pick correct size crimp for the type of wire you are using. Or both at the same time.

There are times you can rush things. Crimping is not one of them. It won't forgive you. I once designed a control system for an industrial dishwasher.There was an intermittent problem on signal wires and it was one of the crimps. It looked fine when you looked at it but obviously I squeezed it too far as I used a cheap radioshack crimp tool. It was not the tool's fault by the way. I still use it and it is great. There were actually ten dishwashers which were prototypes operating in different stores to give us the feedback. Because so much grease was involved after firm crimping I also applied a touch of solder which proved to be much more reliable. However, this was only because of the environment that it was operating in. In normal, dry environment such as audio, regular crimping will be greatly sufficient.

I use idc connectors almost exclusively in my stuff now and i love them. Fast, easy to use and done properly there's no issue...