Hot Rods Soldering electrical connections 101

And when a line did get knocked down, it was rarely a splice connector failure. Winter power outages from fallen trees are common where I live, and it's not uncommon to see a length of line between poles to have multiple butt splices, each one denoting a separate incident. I've seen as many as ten splices between two poles... LOL!

 

But we can take advantage of 25 years of progress to '65, right? LOL...

 

I like solder. I like when I see the good old lead rosin core at garage sales. buy it all. never buy new at the hardware store...fake solder

 

I'm working on something from 1953 right now....I crimped several connections on it today, because I was too lazy to get out the soldering gun. So there.

 

Here in the swamp, crimped connections are green the next time you look at them

 

I solder, there I said it!, ah feels good to come out of the closet! I admit it, I solder!

My plans are always to have the wires clipped or to have brackets holding them in place in a harness this way I don't have to worry about them flapping around in the breeze and breaking the joint and with them secured in clips, brackets and harnesses I don't expect them to see a lot of excess vibration either.

But that's just me

 

Your are correct about proper crimps. When I first started with Freightliner most of the terminals were Packard. The wiring kits the dealers had all the proper crimping tools. Now the repair terminals come pre-crimped on a length of the proper wire and are spliced into the harness.

 

You reminded me that I needed to say thankyou.

I grew up in a house of "insulated terminals, mashed-flat, no heatshrink". I made many repairs that way over the years, and wired my avatar the same. Thought I was a pro, as instead of using the el-cheapo auto store crimpers that come with the terminals I bought a ratchet crimper.

Got the avatar near complete, and drove myself nuts with crappy terminals that either came loose, or broke altogether.

Read the Crazy Steve tutorial, threw out the mash-flat crimpers, and imported a pair of Thomas and Betts. Reterminated the entire wiring harness, and used heat shrink. The crimps are now damn strong, and robust. The Thomas and Betts tool will last a lifetime.

Thankyou for teaching me better (and probably from breaking down in the middle of nowhere).

Cheers,
Harv

 

For more than 40 years I worked in the automotive repair industry. I mostly worked on vehicles built between the mid to late '50s and as new as 2010, 11, 12ish. We live in an area where salt is poured on the roads all winter. I've spent a lot of time over those years fixing wiring under the rear of vehicles that has already been fixed at least once, likely more often than that. Crimp connectors were often used and the repair invariably failed at a crimp where the wire turned green and fell apart. The connector didn't fail but the repair job did.

I always fixed these by replacing any oxidized wire and soldering my splices and using heat shrink to keep the weather out. Of course the harness needed to be supported to help prevent movement and vibration. Obviously my work pre-dates the availability of heat shrink so yes, electrical tape was used to insulate and keep the weather out. I'm betting some of those early repairs didn't live forever, but very probably a lot longer than the quickie crimp jobs done before me.

Soldering is time consuming and if not done correctly, problematic. The correct terminal and crimp tool in the right conditions does an excellent job. I think there is the right time and place for both methods to meet the demands of the job at hand. Both methods need to be done correctly though. If not you may as well just twist the wires together and tape them up. It makes it easier when you have to go back later and fix it right.

 

I represented a company , selling their product, and that was exactly how the factory wired the components! Strip the new wire about an inch each , twist tightly, fold back against the wire and tape! Oddly enough I never had any problems in that area!
Now I am not recommending this method! I was just surprised at how good it actually worked!
I am in the crimp, (or twist) , solder, heat shrink crowd! I used this method successfully for 33 years on the job. But I also supported my wires!
And talk about vibration…… a Fire truck with a Diesel engine , idling for hours at a time will give you a ton of vibration over the years! Never once in that 33 years could I find any failures in my soldered connections!







Bones

 

I can't solder worth a crap and my results have always been similar to yours, which is why I bought a good, ratcheting crimping tool and never looked back. Have wired dozens of vehicles and haven't had an issue with bad connections. I only use non-insulated terminals and cover them in shrink tube that has the glue inside for a weather-proof seal. Works well for me.

I had a conversation with one of the industry-standard wiring company founder's about this exact topic and his opinion was that most people would do more damage trying to solder a connection than what could result in a poorly crimped connection.

 

Use the method you are most comfortable wirh!

The KEY to soldering is flux - dip the wire(s), connector in the flux, also your solder. Use as little solder as you can to coat the connection.

The KEY to crimping is a quality tool - don't go cheap! 30+ years ago, Dad blessed me with a Blue Point crimping tool (off the Snap-On truck) that does everything well - cuts, strips, crimps everything from small-gauge to spark plug wires. KLINE is another excellent brand, sold at better home and hardware stores.

NON-insulated connectors are tricky to find, more-so for good quality commercial grade, in small quanties. I'm always on the lookout for vendors at swap meets, then make up my own assortment with a Harbor Fright box. Worst case, is I pull the insulation off a terminal, replace with heat-shrink tubing for a clean finish.

 

On spark plug wires, most crimpers now are advertised to do 7 and 8mm wire.
8mm dies don’t seem to do a satisfactory crimp on 7mm wire ends , just an observation.

 

By the amount it seems most people actually drive their old cars I really don’t think lifespan of a connection is a factor. Neither will fall apart sitting in a garage.

 

I was in the defense business for almost 40 years. The only thing we really soldered was for satellite work, which fell back on what was called "heritage" methods.

Black boxes, bomb racks, missile launchers, everything was solder sleeves or crimped contacts and terminals. Multi-pin connectors were almost always crimps, outside of solder-cup connectors.

Anything military had to have traceable crimp tooling, which has a certification schedule. On some critical work, we had to list the serial number of the crimp tool and cert date on the traveler. All operators were trained at least once a year.

Even crazier was wire wrap on backplanes. We used to do full-auto wire wrap, semi-auto and by hand. Each job, you'd have to do a sample lot which had to be inspected and pull tested.

 

Make sure you use the wire nuts with "wings". You can screw them on a lot tighter.

 

In my lifetime I can only remember two times a wire came loose from a terminal on a hot rod, stranding the cars. One was my brother's car and one was my Dad's car. Each was a crimped terminal with no solder. One was even a connection applied by a very well known wiring kit vendor.

So, when I wired my car from scratch by myself, I soldered every connection and covered each with shrink tube. I haven't had any come loose yet in the last 15 years.

 

Ahhh...good olde T & B connectors. ‍

 

I've had some failed crimps on a repop harness, as well. I guess they didn't have the tooling set properly. Took years to figure out why one or the other headlight would would blink off occasionally.

Like I said before, soldering and crimping both work great on old cars, if done properly. I didn't start soldering every connection after my bad crimp experience...instead, I learned to give them all the tug test.

 

Yup, I bought a decent ratcheting crimp tool with the die set to fold the end over into that M shape you see in commercial crimps.
Inside the car that's usually where it ends. In an area that sees a lot of moisture (turn signal housings etc) I'll solder them to stop the individual wire strands from wicking the moisture up, rather than to create an electrical connection.

I've had smash-flat crimps fail- they don't cold-weld properly.
I like square-post wire wrap but those are uncommon in most automotive work due to the limited wire size.

The only place I'll solder without mechanical connection is in electronics where the connections aren't subject to any additional stress (push in connectors that aren't supported etc), most of the electronics in my Pontiac are peg to peg construction, with the legs wrapped to form a mechanical bond. The components themselves are more likely to fail before the joints.

So yes, to echo, to do soldering right begins with determining if it is correct to solder the joint, first.
Then, clean, clean, CLEAN. Mechanically clean with sandpaper, then flux. Tinned joint if at all possible to protect the wire surface and aid in soldering. Then, enough heat to flow the solder in and held absolutely still until it cools and solidifies.

Otherwise, a decent crimp will work just as well, if not better, particularly in high current/high heat situations (headlight bulbs and the like).

Phil

 

interesting...it's been about 20 years since I've done any wire wrapping. Worked good for prototyping electronic circuits back when 0.1" DIPs were common.

 

@squirrel nailed it. Proper technique, youtube if needed. Learned to solder in shop class then learned to solder circuit boards in the army.

Buying replacement tips for soldering iron is a great place to start if anyone is having trouble. They won't tin or transfer heat correctly if they're burnt.

I love it when the electrical gurus jump on and explain why soldering is horrible and I must use XYZ solderless joints and the equipment is at least several hundred dollars. These findings are usually based on their experience in a very specific industry that has to meet a very specific specification, usually aircraft or military related. Interesting discussion, but not enough for me to "invest"

 

Rosin-core solder is much easier to use than the new, lead-free solders, and so is more likely to produce a robust joint.

Tin each wire first; then solder them together.

A flux pen ($10 from Amazon) helps the solder flow when the wires have minor corrosion.

 

That reminds me, somewhere I have one of the old, high quality, squeeze type hand wire wrap tools. I wonder if I can find it? I did find my good Panduit wire tie tighten and cut tool.

 

That would be the issue bones, finding a decent pro crimping tool. Feel free to post a good one (Christmas hint for Mrs. Nochop)

 

You'll never convince some people of the superiority of crimps over solder, but truth be told there's no measurable difference in electrical performance as long as the method used is done right. Where the difference shows up is when the connection is stressed. Soldering does change the heat-treat on copper, making it more prone to vibration breakage but good strain relief can eliminate that. But heat is where solder falls down and is where crimping shines. I have NEVER seen a properly done indent-type crimp fail under heat, and I've seen some pretty extreme examples. And if you're having crimp failures, something wasn't done right, it's as simple as that.

I DON'T like the OEM-style 'open' crimps as crimp tool compatibility can vary too much between crimps brands and tool suppliers. While these are the favored type with the OEMs, they also spend the big money for precision crimpers designed specifically for the crimps they use, not a viable option for most of us. You won't have that issue with closed barrel-type crimps and a 'universal' crimper designed for them.

 

A small soldering iron, soldering gun, and propane torch will handle just about any soldering job. I have half a dozen crimp tools, and still struggle with some of them....yeah, there is the tooling issue, too.

 

Lol, hey Steve, that wouldn’t be me your talking about, would it? Lol You have changed my mind…..somewhat! You are right about the “ factory” crimps I had trouble with! They were not done properly! But I still had trouble with them, that is why I still have a little trouble with just crimping alone! I don’t advise soldering anymore…..unless some other folks mention it first!
My method was successful for 33+ years and I was not aware that soldering was unacceptable in some places.
Like I said, with me old habits die hard. But I also make a mechanical connection before I solder, and I have the right tools and skill to solder, so maybe that is why I have been successful all these years!
I still testify , solder, just don’t preach it any more!






Bones

 

The one I use is one that I have used for years.I don’t think I have a picture of it, can’t get to it right now. But it’s made by several tool makers, Thomas and Betts (?), Klein and several others. Maybe someone here could post a picture of them.
Crazy Steve uses aa old one but they are hard to find. See the thread “ Wiring 101”.
The trick to using one of these crimper s is to use the right size and make sure the dimple is on the solid side of the terminal. I use uninsulated terminals and then insulate after connecting if necessary.








Bones

 

Wrong way


Right way