Why the Insulation on Wire Connectors?

[SSTJ]

Many wire connectors come with color-coded insulation, like in the picture below. I find that they just seem to get in the way when crimping. They prevent me from seeing the quality of the crimp I've made, and they make the connection a bit bulky and clunky (especially when several wires are being crimped right next to each other), and they make it more difficult to choose a heat shrink that will fit the insulated connector while still fitting snugly on the wire.

I've gotten into the habit of removing the insulation, or buying non-insulated connectors altogether. But I'm surprised by how much less common they are. Am I missing something? Or do most people just not use heat shrink and rely on these as their only insulation?

 

[P man]

I personally hate the connectors like that. I use bare terminals that are crimped properly with quality pliers and shrink wrap.

 

[freedom_in_4low]

I think most people that use those don't heat shrink them. It's basically equivalent to a residential wire nut at that point but I don't like using them because i like my wiring looking factory.

 

[g.hayduke]

I use terminals that have semi-transparent colored heat shrink for insulation and strain relief.

 

[MikeE024]

I think most people that use those don't heat shrink them. It's basically equivalent to a residential wire nut at that point but I don't like using them because i like my wiring looking factory.

I don’t like that they could break and allow for corrosion. I use heat-shrink crimps for almost everything. Keeps stress off the crimped strands and better incapsulates the copper. This is why I typically use butt connectors instead of bullet or spade connectors.

 

[freedom_in_4low]

I don’t like that they could break and allow for corrosion. I use heat-shrink crimps for almost everything. Keeps stress off the crimped strands and better incapsulates the copper. This is why I typically use butt connectors instead of bullet or spade connectors.

Same, I use the ones with heat shrink already on them.

I don't think I've ever used spades where I'm connecting two wires...only the female ends where it's connecting to a spade pin on a switch or relay. I have used bullets as a substitute for a connector where being skinny was advantageous for how big of a hole I had to drill. But again, they were the heat shrink type.

 

[SSTJ]

I don’t like that they could break and allow for corrosion. I use heat-shrink crimps for almost everything. Keeps stress off the crimped strands and better incapsulates the copper. This is why I typically use butt connectors instead of bullet or spade connectors.

Could you say more about this? Stress on the strands is what holds the connector in place, so do you mean there such a thing as too much stress on the strands?

 

[MikeE024]

Could you say more about this? Stress on the strands is what holds the connector in place, so do you mean there such a thing as too much stress on the strands?

Vibration/stress can lead to the individual strands breaking, which I’ve seen happen countless times (on vehicles and fighter jets). If you heat shrink it, the glue grips on the insulation not just the small little strands that can break. This preserves the mechanical connection at the strands bc they won’t be yanked on.

If you throw a more pliable heat shrink tubing over the splice that will relieve things even more (I only do this when necessary)

 

[SSTJ]

Vibration/stress can lead to the individual strands breaking, which I’ve seen happen countless times (on vehicles and fighter jets). If you heat shrink it, the glue grips on the insulation not just the small little strands that can break. This preserves the mechanical connection at the strands bc they won’t be yanked on.

If you throw a more pliable heat shrink tubing over the splice that will relieve things even more (I only do this when necessary)

Understood. So you do still use a crimp, without the nylon insulation, and you use adhesive heat shrink over the crimps. Right?

Got a recommendation for the adhesive heat shrink?

 

[MikeE024]

Understood. So you do still use a crimp, without the nylon insulation, and you use adhesive heat shrink over the crimps. Right?

Got a recommendation for the adhesive heat shrink?

I prefer heat shrink butt connectors…used them hundreds of times with no issues. You just crimp for the mechanical connection and then melt. I’m also a fan of using wire loom to protect the wiring and cleaning up the appearance.

 

[mrblaine]

Understood. So you do still use a crimp, without the nylon insulation, and you use adhesive heat shrink over the crimps. Right?

Got a recommendation for the adhesive heat shrink?

You picked the very worst possible group of terminals to judge all the alternate methods by and skipped a whole bunch inbetween to jump to a good but not univeral answer.

There are lots of translucent nylon insulated terminals that are used with a crimper that gets the wire and then a separate barrel gets the insulation on the wire to provide strain relief. The see-through nature allows you to view the crimp. The funnel entry is also very useful.

https://www.elecdirect.com/crimp-wire-terminals/ring-crimp-terminals/nylon-ring-terminals

We use a lot of those with the proper crimper and we've never had a single failure. There is no need to add the bulk and time for heat shrinking every terminal for something like a row of switches and gauge in the dash.

These crimpers are specifically made for those terminals. They crimp on the wire and then secondarily on the insulation.

https://www.elecdirect.com/tools/crimp-tools/ratchet-tool-for-nylon-terminals-22-10-awg

The other issue that arises is you may not want the wire to stay straight and unbendable inside a heatshrink terminal which also tends to be bulky.

I'm a big fan of and use tons of brazed or solid barrel butt connectors with adhesive lined heat shrink. Sherco has some nice translucent stuff, the only problem with it and any of the other stuff in that style is the size. We use the red in place of blue and blue in place of yellow.

Economically, Wirefy has some stuff on Amazon. The 3-1 is good, very good actually. I like that it is thin and the adhesive has a lower melt temp so you don't affect the wire insulation. Regardless of what you use, get a good heat gun to shrink it with.

https://wirefyshop.com/

I don't have much experience with other than their adhesive lined heat shrink in 3-1. I see a lot of stuff that looks tempting to try, I just haven't.

 

[mrblaine]

I prefer heat shrink butt connectors…used them hundreds of times with no issues. You just crimp for the mechanical connection and then melt. I’m also a fan of using wire loom to protect the wiring and cleaning up the appearance.

I prefer to apply heat shrink to solid or brazed barrel uninsulated butt connectors. The heat shrink versions while good for a lot of things, are pretty bulky and sometimes that matters a bunch.

That and the step down heat shrink connectors are not very economical.

 

[SSTJ]

There are lots of translucent nylon insulated terminals that are used with a crimper that gets the wire and then a separate barrel gets the insulation on the wire to provide strain relief. The see-through nature allows you to view the crimp. The funnel entry is also very useful.

https://www.elecdirect.com/crimp-wire-terminals/ring-crimp-terminals/nylon-ring-terminals

I had forgotten about the translucent nylon. Thanks.

We use a lot of those with the proper crimper and we've never had a single failure. There is no need to add the bulk and time for heat shrinking every terminal for something like a row of switches and gauge in the dash.

These crimpers are specifically made for those terminals. They crimp on the wire and then secondarily on the insulation.

https://www.elecdirect.com/tools/crimp-tools/ratchet-tool-for-nylon-terminals-22-10-awg

Yes, I have one of those. This is a good reminder that the design of those 'jaws' is to perform both tasks: setting the terminal on the wire strands, and setting the insulation on the wire sheath.

The other issue that arises is you may not want the wire to stay straight and unbendable inside a heatshrink terminal which also tends to be bulky.

I'm a big fan of and use tons of brazed or solid barrel butt connectors with adhesive lined heat shrink. Sherco has some nice translucent stuff, the only problem with it and any of the other stuff in that style is the size. We use the red in place of blue and blue in place of yellow.

Thanks. Yes, we covered that in another thread, I remember now.

Economically, Wirefy has some stuff on Amazon. The 3-1 is good, very good actually. I like that it is thin and the adhesive has a lower melt temp so you don't affect the wire insulation. Regardless of what you use, get a good heat gun to shrink it with.

https://wirefyshop.com/

I don't have much experience with other than their adhesive lined heat shrink in 3-1. I see a lot of stuff that looks tempting to try, I just haven't.

Good to know about. I'l pick some up for the occasions in which I use a non-insulated terminal. I'll also add it to the other thread I mentioned above, here.

 

[MikeE024]

You picked the very worst possible group of terminals to judge all the alternate methods by and skipped a whole bunch inbetween to jump to a good but not univeral answer.

There are lots of translucent nylon insulated terminals that are used with a crimper that gets the wire and then a separate barrel gets the insulation on the wire to provide strain relief. The see-through nature allows you to view the crimp. The funnel entry is also very useful.

https://www.elecdirect.com/crimp-wire-terminals/ring-crimp-terminals/nylon-ring-terminals

We use a lot of those with the proper crimper and we've never had a single failure. There is no need to add the bulk and time for heat shrinking every terminal for something like a row of switches and gauge in the dash.

These crimpers are specifically made for those terminals. They crimp on the wire and then secondarily on the insulation.

https://www.elecdirect.com/tools/crimp-tools/ratchet-tool-for-nylon-terminals-22-10-awg

The other issue that arises is you may not want the wire to stay straight and unbendable inside a heatshrink terminal which also tends to be bulky.

I'm a big fan of and use tons of brazed or solid barrel butt connectors with adhesive lined heat shrink. Sherco has some nice translucent stuff, the only problem with it and any of the other stuff in that style is the size. We use the red in place of blue and blue in place of yellow.

Economically, Wirefy has some stuff on Amazon. The 3-1 is good, very good actually. I like that it is thin and the adhesive has a lower melt temp so you don't affect the wire insulation. Regardless of what you use, get a good heat gun to shrink it with.

https://wirefyshop.com/

I don't have much experience with other than their adhesive lined heat shrink in 3-1. I see a lot of stuff that looks tempting to try, I just haven't.

Regarding your first paragraph, I think we are talking about similar butt connectors. I use these 99% of the time. Just pulled them from my kit that goes with me on adventures.

I have the same style for ring connectors, bullet, and spade connectors but I rarely use them and will likely have them for decades due to non-use. I got the bullet style for my friend’s horse trailer since that’s what his market lights take. That trailer’s wiring was jacket so I gutted it all, and helped him get a $800 charge back bc the wiring job he paid for was exposed and shorting out on the trailer (lazy ignorant dudes getting paid hourly like they are experts).

Regarding my preference for a heat-shrink crimped butt connector, I’m game to use something different the second they fail or won’t work for a task, but that’s not been an issue so far. But, I basically refuse to use a crimp butt connector that does not have heat-shrink insulation. I prefer the connection to be sealed up and better stress relieved. I also I capsulate my diodes using the same butt connector to stress relieve them.

I just got to PHX so I can’t nerd out on this as much as I’d like to. I’ll catch up with everyone later on this.

 

[SSTJ]

Regarding your first paragraph, I think we are talking about similar butt connectors. I use these 99% of the time. Just pulled them from my kit that goes with me on adventures.

View attachment 504554

View attachment 504555

I have the same style for ring connectors, bullet, and spade connectors but I rarely use them and will likely have them for decades due to non-use. I got the bullet style for my friend’s horse trailer since that’s what his market lights take. That trailer’s wiring was jacket so I gutted it all, and helped him get a $800 charge back bc the wiring job he paid for was exposed and shorting out on the trailer (lazy ignorant dudes getting paid hourly like they are experts).

Regarding my preference for a heat-shrink crimped butt connector, I’m game to use something different the second they fail or won’t work for a task, but that’s not been an issue so far. But, I basically refuse to use a crimp butt connector that does not have heat-shrink insulation. I prefer the connection to be sealed up and better stress relieved. I also I capsulate my diodes using the same butt connector to stress relieve them.

I just got to PHX so I can’t nerd out on this as much as I’d like to. I’ll catch up with everyone later on this.

Thanks for this. Might be helpful to post this over here, where we have some recommendations on best connectors.

In this thread, I was mainly wondering why the nylon insulation was so common, and whether I was missing some reason to consider using that style.

 

[PCO6]

The colour coded plastic insulation is handy for knowing what gauge wire they are for but I always pull them off and use heat shrinks. You can buy connectors without the insulation but the ones with it are so commonly available that's what I go with. The insulation on colour coded butt connectors is not easy to remove so I stock up on uninsulated ones and use heat shrinks.

 

[mrblaine]

Thanks for this. Might be helpful to post this over here, where we have some recommendations on best connectors.

In this thread, I was mainly wondering why the nylon insulation was so common, and whether I was missing some reason to consider using that style.

I think if you dig into it further, that very common crap style are vinyl insulated, not nylon. Nylon, especially in the translucent styles makes for a very good connector.

 

[mrblaine]

Regarding your first paragraph, I think we are talking about similar butt connectors. I use these 99% of the time. Just pulled them from my kit that goes with me on adventures.

Had you gone to the link I posted, you would have discovered that we are in fact not talking about the same thing at all. I referenced the dual zone crimp that gets the wire strands and then another section over the insulation for strain relief along with funnel entry for easier wire insertion.

View attachment 504554

View attachment 504555


Regarding my preference for a heat-shrink crimped butt connector, I’m game to use something different the second they fail or won’t work for a task, but that’s not been an issue so far. But, I basically refuse to use a crimp butt connector that does not have heat-shrink insulation. I prefer the connection to be sealed up and better stress relieved. I also I capsulate my diodes using the same butt connector to stress relieve them.

I just got to PHX so I can’t nerd out on this as much as I’d like to. I’ll catch up with everyone later on this.

I have and use a lot of that style butt connector. I also have and use a ton of the solid and brazed barrel non insulated style with separately applied adhesive lined heat shrink in 3-1 ratio. They both have their place. The combo style is faster but bulkier. The other one is far less bulky which matters when you're trying to get a harness through a grommet or you don't want your loom to resemble a python that just ate your neighbor's dog.

 

[SSTJ]

I think if you dig into it further, that very common crap style are vinyl insulated, not nylon. Nylon, especially in the translucent styles makes for a very good connector.

Aha, thank you.

 

[mrblaine]

Aha, thank you.

If you pay attention, they will show it as PVC or polyvinyl chloride.

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