What do the experts say about wiring: crimp, solder, then heat shrink, or ?!?!?

Luxblue,
You always seem to make me laugh. Now you got me thinking about how to get proper sealing to shoot a car out of a cannon. Good point about the loop being down. I call a drip loop just for that reason.
Another little tip I have used to make things all nicey nice is when routing.Use a piece of welding rod and run it in your bundle. Keeps it stiff enough to do some really nice routing and it will help support the bundle.
And as Bob pointed out, a loop clamp or adel clamp in the right place is a must.
This is a good thread. I will see about adding some examples via pics.
Fitysix

 

Fitysix,
Nice tip on the welding rod to stiffen a bundle of wires. Never thought of that. Thanks.

 

Seems to me that the "traditional" way to make an electrical connection would be to twist the wires together and then wrap them with electrical tape. At least that is the way we did it when I started building cars in the 60's. I am sure glad we do not do it that way today.

John

 

If you can do it without it becoming an abrasion point, go for it. This of course violates any military or commercial wiring practice that I've seen.

Bob

 

What? No wire nuts?

 

I have 37 years of broadcast electronic tech work experience. I use both and solder is the most reliable. I have never had a solder joint fail for any reason. I have had some crimps work loose. This was due to using the wrong wire size crimp for the wire. I say it is a matter of preference and skill level. Word of caution though, if you are soldering make sure you really know how to properly make a solder joint. If crimping make sure you use the proper size terminal for the wire gauge you are working with. When stripping the end of the wire don't undercut the strands or exert to much pressure when making your crimp this can also lead to failure by cutting into the wire.

 

yup, and I've seen a few that had wire nuts instead of tape!

It's traditional for your electrical system to give you trouble, guys....

 

i just crimped everything and heat shrink as well... have had no problems in 10 years

 

About the welding wire. No it is not a practice used in military or commercial practices but, it works. If you use a little common sense and not put the end of the wire in the radius of the bend it will not be a factor. I usually double back the ends into a loop and cover the loop with shrink tube or tape. They do make a product used in commercial apps that work on the same principle.
Shadetreerodder....you are correct in that there are correct ways and incorrect ways to solder. Just like with anything else it comes with practice. Cold solder joints are the most common mistake I find with beginners.
Fitysix

 

I don't want to argue with this spec or that spec, but for me so far, every single time I had to track down the source for a flickering light, or scratchy speaker sound, or a new fuse that acts like a bad one, it seems it has always been tracked down to a bad connection at an old unsoldered crimp, or a dirty rivet holding a lug to a fuse connector.

I like crimp-then-solder for my projects because of the greatly increased contact area for p***ing current, and great corrosion resistance.

I hate tracking down slowly failing connections due to crimp-only connectors with increasingly higher and higher resistances resulting from two deteriorating surfaces touching each other.

I am not an engineer. It's just my preference. I solder for my own peace of mind.

 

The newer crimping pliers that ratchet the crimp to a preset amount are much better than the older pliers that you just squeeze until it felt right or until it was all you could do. In addition to making a wider crimp, they crimp the insulated barrel to prevent the wire from moving back and forth. Most crimps fail at the end of the metal crimp inside the insulated barrel. Thus if you crimp the plastic insulated barrel it keeps the wire from moving. I gave about $50 for mine but I recently bought a set for my brother at Harbor Freight for $14. His look identical to mine.

I use a lot of crimps and I buy the good ones. Most of the time I heat shrink over the top of them but that is mostly so that I do not have to look at the ugly crimp connector. One thing to look for in a better connector is that the inner part of the crimping barrel will have serations, while the cheaper ones are smooth. I still solder some critical connections because it makes me feel like I am doing a better job but I am not sure that it is true.

My last thought is that everyone should throw away all those little blue wire splicers. The ones that people use to tap into another wire. Most of the time they are used on tail light circuits when someone splices into the circuit for trailer wiring. These things are junk and have caused me many hours of work over the years sorting out someone elses electrical problem that I finally traced back to these connectors. They are absolute junk.

John

 

I crimp only with a Stacon tool--use bare connectors and heat shrink. Have done alot of cars with no issues. For battery cables (1/0) I use a compression tool usually used for high voltage overhead line splices. Most if not all overhead connections are compression-whether it be house services or 500KV transmission lines-these see tremendous vibration and constant load/heat changes.

 

When I rewired my 49 I pretty much followed the advice from MAD Electrical since I was a complete novice. I read most of the tech section on his website and ordered much of my early stuff from him.

I used non-insulated connectors and if I couldn't find the non-insulated ones, I heated the plastic on the insulated ones with a heat gun and pulled off the plastic. Then Crimped using a Klein 1006 crimper about $24 (not the cheap striper/crimper from a hardware store) these crimps are super tight. Then soldered using a Weller soldering gun (got the deluxe kit from Menards which comes with a plastic carry case and a 2 heat gun) Then 1 layer of electrical tape followed by shrink wrap.

The wires are wrapped with high temp wire loom available from Wiring Products. I also used wire from Rebel Wire a HAMB Alliance vendor-the wire is American made SXL wire and it was great.

 

The minions of Satan You speak of are called scotch locks. They are the second biggist peice of **** invention to ever make it off of 3m's production floor.

Thier entire premise for use and installation is LAZINESS. The biggist peice of **** beyond them is a term-Lock. that combines the ****ty scotch lock with a spade terminal to not only ***ure 1 ****py connection, but 2.

I hate these things with Venom and avarice. Here in Texas, everything short of big bottomed women has a Trailer hitch on it. seemingly every bit of trailer hitch wiring was done with scotch locks. Next time You see a truck with no trailer lights at all, or 1 really dim taillight, and 1 bright one, look for the trailer hitch. guaranteed, The wiring to it is attached with scotch locks. every stero that clips out that some dingus had installed by the "pros" over at circut city (who were surely there part time from MDonalds) is scotch locked into place.

God, I hate those things so much.....

 

funny, just learned that last night.

 

if you can get a hold of him that is. But I guess you got to get in line to talk to the best.

 

Couldn't agree more. Doesn't get any better than that.

 

For the lugs that get screwed down, I use crimped insulated lugs, but I solder them from the terminal end. If you hold the soldering iron (gun type) at the opening where the wire strands are poking through the crimped metal part inside, it's easy to get solder to flow in there. I also usually put a length of heat shrink over the wire first and then slide it over the insulator and shrink it so that it completely covers the insulator. That works like a strain relief and it also looks nicer I think. I use a pocket knife to scratch any of the rosin core flux that might wind up on the surface of the lugs where they get screwed down.

For connections that are exposed to the weather, I use that heat shrink that has another layer inside that melts to seal everything up hermetically.

For **** connections, I usually just twist the wires together and solder them and put two layers of heat shrink to give the connection area some extra strength. Make sure there are not sharp strands sticking out from the soldered joint that might poke through the heat shrink.

If you use the bullet style inline connectors you have to be careful if you use heat shrink over the female bullet connector. If you heat up the insulated barrel around the female part, the barrel shrinks, making it almost impossible to stick the male end into it. If you use heat shrink on the female side, just keep the heat gun out at the wire end of the connector only.

I've never had an electrical wiring problem in any of my cars that I put together, so I guess it pays to go to the extra effort to make good solid soldered connections.

Most people who I've seen have problems -- it always turned out to be a poorly crimped joint that wiggled around and got corroded inside the connector, or a wire that just plain fell out of the connector, or a wire going through a sharp hole in sheet metal where there should have been a rubber grommet.

Another mistake people make is using connectors that are the wrong size for the wire they're using. Like using a connector made for 10-12 gauge for a 20 gauge wire.

If you need to put a smaller wire into a larger connector, sometimes you can fold the end of the wire back onto itself and smash it so it fits into the connector. Like folding over an 18 gauge wire makes it fit okay into a 14-16 gauge connector.

If you put multiple wires into one crimp connector, twist all the wires together tightly before pushing it into the connector. Make sure ALL of the strands of the wires are going through the metal part of the terminal.

 

Use alcohol to clean flux off the soldered joint (not rubbing alcohol).

 

For circuit repairs in the ***embly plants, we instruct the repairman to ALWAYS solder and heat-shrink. When it comes to connectors and terminals, it's the same thing.
When the electrical harnesses comes from the supplier its terminals are just crimped to the wire and the terminal is insterted into a connector shell. Sometimes we end up with a cold-crimp (the terminal is crimped to the insulation but makes no contact with the wire core).
All ground lugs are soldered and crimped.
I hope this helps.
Now... practice, practice, practice!