solder vs crimp

[Colin]

When i started SAE i was responsible for the Electrical system, from my electrical background i always thought that solder was the go, when our ECU supplier saw all my solder joints they were not impressed, their theory was that solder wicks down the wire and makes the connection more susceptible to vibration, after this spiel they then offered to sell me their crimp tool for a huge amount of money. http://fsae.com/groupee_common/emoticons/icon_wink.gif
The next year I bought the tool and crimped every connection on the car, also did the same for the data-logging loom. I'm now sold on the crimp theory and don't solder anything on the car anymore unless I have to.
I'd be interested to know what other teams do in this area?

[Colin]

When i started SAE i was responsible for the Electrical system, from my electrical background i always thought that solder was the go, when our ECU supplier saw all my solder joints they were not impressed, their theory was that solder wicks down the wire and makes the connection more susceptible to vibration, after this spiel they then offered to sell me their crimp tool for a huge amount of money. http://fsae.com/groupee_common/emoticons/icon_wink.gif
The next year I bought the tool and crimped every connection on the car, also did the same for the data-logging loom. I'm now sold on the crimp theory and don't solder anything on the car anymore unless I have to.
I'd be interested to know what other teams do in this area?

[Garbo]

Last year, our electrical guy crimped every connection... and they all came loose. I (a chassis guy) re-wired the car completely, soldering every connection and we never had another problem for that year. Since then, we've soldered with no more electrical problems. But, the crimped connections took us out of the competition in 2003.

Garbo

[Storbeck]

For what it's worth, The Motec guy at the Claude Roulle seminar said almost exactly the same thing about solder vs. crimp. (might have been the same guy)

[Bob T]

We crimped every electrical connection both this year and last. If you are still really concerned coat the crimped connections with the solder to reinforce it. When crimping always make sure to tug on the wire(s) a bit after you crimp just to make sure it's crimped well. We got about 8 potentially loose connections that way while making the wiring harness last year.

Bob

[Dan Deussen @ Weber Motor]

First crimp....
Then solder....

This makes it almost foolproof. I would especially suggest this if you don't have the exact crimping tool that is recommended by the pin manufacturer.

[Igor]

A proper crimp will not need any soldering at all. I would even say that the difference in thermal expansion between the solder, copper and terminal will work the wire loose over time.
As Dan said, you will need the proper ratchet tool from the pin manufacturer (which will set you back about $100-200). If you see anyone using the $5 one that looks like a flat pair of pliers, crimp some battery terminals on all their extremities. Trying to remove those should convince them on the quality of crimping :-)

Think about it; aerospace - no solder, military - no solder, medical - no solder, automotive - no solder, mechanical engineering dude at FSAE - messing around with solder....
If you insist on using a generic crimping tool, tug on the result to test them for durability and think about some kind of strain relief.
I know it's hard to explain to all the mechanical engineers why you need a $100 pair of pliers for some connectors, but just remind them you didn't complain when they bought a $200 torque wrench and didn't even do an engine rebuild :-)

Ok, end of rant. Happy crimping.
Igor

[Chris Boyden]

Crimping is the way to go. But, here's the deal, it has to be done right. Like Igor said, If you're gonna crimp, you have to have the ratcheting crimping tool designed for the connectors that you are using. Don't skimp on the electrical system. The 100 to $200 spent on that crimper is a great investment. The Deutsch crimper for solid contacts provides an airtight and corrosion proof crimp with 8 pressure points. I love that tool, I only wish that I had found it sooner http://fsae.com/groupee_common/emoticons/icon_biggrin.gif. Without a solid electrical system, you don't have a solid car.

Soldering hardens the wire, making it more susceptible to work hardening from vibration, which ultimately leads to failure.

A good pair of wire strippers is gonna be my next investment. If the wire is cut because the strippers suck, that also comprimises the connection.

[Sam Zimmerman]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Igor:

Think about it; aerospace - no solder, military - no solder, medical - no solder, automotive - no solder, mechanical engineering dude at FSAE - messing around with solder....
If you insist on using a generic crimping tool, tug on the result to test them for durability and think about some kind of strain relief.
<HR></BLOCKQUOTE>

I don't know about aerospace or medical but I do know that milspec connectors are soldered amp connectors, used on everything from B-57's to ships. I have also seen the same connectors on Bridgeport mills and lathes, nearly every piece of equiptment in GM's powertrain plant, and even a F1 wiring harness. I am a big fan of solder over crimping, I just need to watch closely to make sure people do it right. If I see an F1 wiring harness with crimp-on connectors I might change my mind.

[BryanH]

"milspec" connectors that you see on race cars use solid pins crimped with Deutsch crimper,a truly beautiful bit of gear. Bosch terminals and similar are done with AMP crimper. By the way, Over here the AMP is A$330 and Deutsch is over A$500! but I consider worth every cent
I do EFI install/mapping for a living so what would I know?

[BryanH]

that milspec connectors are soldered amp connectors, used on everything from B-57's to ships.

P.S. If they had soldered every pin on every plane/ship they would still be building the frigging things

[Igor]

Ok, there might be a mil-spec for soldering connectors that have solder buckets. Mil-spec does come in many varieties.
The Deutsch connectors on our Le Mans cars are all crimped. I think there would be ass-whooping if someone tried to mess about with a soldering iron.

I once visited with a company that make wafer fab equipment, they sent their crimp tools back to the factory for re-calibration every month. Talking about being anal.

Igor

[IsheeM]

Where are you guys getting these crimp tools from? A standard supply house or just the same place you buy your wiring and other connectors?

[Chris Boyden]

Try Ladd Industries for a really nice Deutsch crimper and connectors. These connectors are really nice. They are the easiest connectors I've ever used. You can actually take them apart without damaging them with a set of needle nose and a small flat blade screwdriver.
Plus they are waterproof to 3 feet underwater(haven't tested that, but that's the spec). They come in a bunch of styles and have silicone seals to keep em clean and dry.
We paid 180 bucks for the crimper HDT48-00 field tool for solid contacts.

www.laddinc.com (http://www.laddinc.com)

[Charlie]

Our electrical guy this year was incredibly anal and did a fantastic job on our electronics systems. He soldered everything. Talking to MoTec, they recommend crimping for the reason stated earlier: solder can wick down the wire and cause a vibration failure.

My opinion is this:

Best choice is to buy the high $$$$ crimping tool for every connector you use, and use no solder.

Good choice is to crimp each connector with the $10 crimp tool, and solder the connection, using solder sparingly.

Worst choice is to use the $10 crimp tool alone.

We've had lots of failures from crimps in the past. Never a solder failure, and we have lots of solder joints. I don't doubt there is a good reason to use a (proper) crimp with no solder, but I would be willing to bet that the failure rate od solder joints due to vibration is much, much much less than the failure rate of a standard crimp.

[Chris Boyden]

Agreed,well put Charlie.

[Sam Zimmerman]

Nicely put, Charlie. Since I have never seen a solder connection fail but have seen many, many crimped connectors fail, we will stick to soldering the connectors (with a bit more oversight than before.)

Halfast, I never suggested that every pin on every plane and ship is soldered but that was a nice attempt at taking a statement, turning it into an absolute, and using it to try and prove a point. You must have a future in politics.

[Denny Trimble]

We've had a couple solder joints fail, but usually because something else was done poorly, i.e. zip-tying a wire to the frame with a connector dangling off it, which fatigued the solder joint going into the connector. Now we make sure to zip-tie the connectors themselves to the frame, not the wires leading into them.

[Chris Boyden]

Yep, strain relief is important no matter how you do the connections. Several of the connectors have plastic and metal mounting bracket options that would be pretty cool....but zip ties work well too. It's definitely something I wanna improve on.

Another thing to look at as far as connectors and wiring is the number of plug/unplug cycles a connector can take without crapping out on you. The AMP connector on the '03 car TEC3 computer is only rated for 10 plug/unplug cycles. Well, we exceeded that big time, and the car would spontaneously stop running, lock up injectors open and fill cylinders with gas, or spit and fart and wouldn't start. Then if I held my tongue just right, cross my fingers, and jiggle the harness, everything would go back to normal. It started to really piss me off because it made the engine completely unreliable, so we're replacing the harness.

[BryanH]

Quote Sam Zimmerman
------------------------------------------------
Halfast, I never suggested that every pin on every plane and ship is soldered but that was a nice attempt at taking a statement, turning it into an absolute, and using it to try and prove a point. You must have a future in politics.
------------------------------------------------
Sorry Mate, too late at night, too much Merlot.

We now live in an age when anybody can buy a very sophisticated EMS over the counter then take it home and attempt to install it. From what I have seen 90% of them don't have the training to do a proper job of it. And it is the really complex systems like the m800 Motec or E11 haltech that suffer the most.
A relatively simple system is less drama to setup and tune and with a neat well made loom will make more horsepower than the dogs balls not mapped correctly.
When I do solder wires/terminals I use an instant heat high power iron and try to solder the last 4mm of wire to the term, keeping the solder time under 2 sec. I never use those white nylon/bullet term connectors -they are rubbish. If your ECU uses one of these cut it off and fit something better
Use Deutch,bosch or delco weatherpak, don't use any tape, insulate with shrinkwrap - it just takes a bit more planning before you start terminating. Regards Bryan Hester

[D@UTA]

I have been responsible for the electrical on the 2003 and 2004 car and rewired the 2001 1999 car (in process), and I am a support of solder if you are very careful. Dot put more solder than you need on there, and keep the heat on a little as possible. Also make sure everything is strain relieved with heat shrink and never ever use tape! Every connection I make is done with solder and cover about a half and inch on each side with "glue" style heat shrink. I just don't trust a crimp, and I'm very careful when I solder. So far there have been no problems with any of the cars I have wired. Also, I do not use pig tails when ever possible. Its much nicer, and relaible if you make every connection your self, for the simple fact that I know my solder joints are good. Also the highest place for a failure is at a joint, so if you can eliminate a joint do it.


Denver
UTA
('02,'03,'04,'0......)

[Rroman]

Hi.After reading all the post and doing a search at the internet, It is`nt clear what`s better, so:
At the end of the day what`s better:

Crimping with a cheap tool, soldering or crimping and soldering?

Ricardo Roman

[Colin]

Gee's where did you dig this thread from? as for your question Charlie pretty much nailed it with his post

[DaveC]

I've wired several vehicles, solder combined with adhesive lined shrink wrap is the way to go. Never had a problem with soldered connections, I've seen plenty of crimps fail. I had a crimped battery cable not be able to transfer enough amperage to keep a battery recharged on a Landcruiser (w/ Vortec 350) I owned, I soldered it, and no more charging problem. You could tug on that connection, and it felt solid. As far as solder wicking down the wire, how long are you going to leave the heat on the wire? That seems absurd, but I guess someone has managed to do it. I also use doetch (sp) connectors, with the pins both soldered or not, no problems either way. I wouldnt solder the pins using GM weatherpac or doetch connectors, just use a good crimp tool. The connectors provide adequate strain relief.

[Kurt Bilinski]

I work at an aerospace company. We crimp all the cable assemblies. My personal opinion is if there's any vibration, the soldered connections will fail right at the solder/wire interface.

This said, you *must* use good crimping equipment. For example, AMP's crimpers are $300-$500... but they never fail.

[DaveC]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> My personal opinion is if there's any vibration, the soldered connections will fail right at the solder/wire interface.
</div></BLOCKQUOTE>

Hmmm... dont tell this to my '74 k20 with a 600 hp BBC (completely rewired), or my rally car, or the dozen or so car stereo installations I have done, or the landcruiser with the 350 Vortec motor (sold it a few years ago), etc, etc, etc. I have owned my own welding/auto shop for over 2 years before going back to finish my degree, and have yet to have any of my solder joints fail, and have never had a complaint about any of my wiring, and I have done A LOT of it. Just my experience...

[Garlic]

Wow Dave, you're right. I'm sure your project cars (however cool) give you far more experience than a manufacturing environment. Especially aerospace. I mean, what do they care about relability?

I've had two wires twisted together on my rear speakers in my car for 3 years... no problems! I guess that's a good example of what to do.

Solder is pretty good, and for anything strain relieved it probably going to work fine. But proper crimping will not come undone and will maintain proper contact, without the added risk of fatigue failure that solder brings.

Talk facts, theories, or reasons, not 'Tell that to my uber experience that trumps all'

[Bryan Hagenauer]

I work for a milspec/autosport wiring company, and if I tried to solder some wires together I'd probably get fired.

There is no substitute for proper tools. Another thing not mentioned here is once you've spliced the wire, wrap the whole thing in SCL. http://www.raychem.com/resources/documents/datasheets/Cable_Protection/Scl.pdf This is a fairly stiff shrinkwrap that has a good adhesive on the inside, providing strain relief. The completed splice+SCL should then be wrapped with heatshrink along with the rest of the wire.

[Courtney Waters]

I agree that crimping with a proper mil-spec tool and mil-spec connectors is THE way to go, but... let us not forget one significant fact - not all teams have reams of cash with which to operate. As has already been noted, the high quality crimpers are rather expensive, and the connectors & pins are not cheap either.

Since our wiring was done on the cheap (mostly Del City stuff) I crimped each connection, tug-tested it, and then put a dab of solder on the end of the wire to secure it to the terminal to keep it from pulling through. This kept the solder from wicking down the wire. Followed up with heat shrink (for insulation and strain relief) and plenty of zip ties & tape to loom the harness. Everything was well-secured to the chassis as well. To the best of my knowledge, both cars wired this way haven't had any failed electrical connections.

Automotive (at least the older stuff I'm most familiar with) had both spade connectors & eyelets with built-in strain reliefs (a second set of crimps that gripped the insulation). Anyone know where to get those or a quality tool to crimp them?

[DaveC]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Talk facts, theories, or reasons, not 'Tell that to my uber experience that trumps all' </div></BLOCKQUOTE>

Thats why I said "just my experience". Take it at that. I didnt say its the ultra-ultimate, better than all way to do it. I don't doubt that a $500 crimp tool will do a good job, and may be better than solder. I'm just stating that solder combined with adhesive lined shrink tubing will work, and it will not break, probably for tens thousands of miles in a typical vehicle installation.

Look, if you think its worth it to invest $1000 in wiring accesories to put this car's wiring together, have fun, great, it'll probably be technically better than anything else. It's just not necessary.

[DaveC]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Automotive (at least the older stuff I'm most familiar with) had both spade connectors & eyelets with built-in strain reliefs (a second set of crimps that gripped the insulation). Anyone know where to get those or a quality tool to crimp them? </div></BLOCKQUOTE>

Any hardware store. Klein sells a decent crimper for these connectors. Looks like a big set of dykes with a couple of notches, one for the wire, one for the insulation strain relief. That said, I don't like spade connectors at all, but lots of automotive gadgets use 'em, so I take the insulation off the spade thingy, crimp it on the wire, apply a LITTLE tiny bit of solder, use a piece of adhesive lined shrink tubing to the base of the spade, then cover the entire spade in non-adhesive shrink tube. If it doesnt require a good push to get the spade on there, use a little pair of needle nose pliers to make the connection a little tighter. Its STILL not a very reliable connection, some people might prefer to solder a legnth of wire onto the spade, then use a weatherproof pin type connector to make the connection. I'd avoid using any device that uses spades on a vehicle where the connection coming loose is going to be a big deal. I have some on my truck, but I dont want to see them on my rally car, or our teams fsae car.

[flybywire]

Flogging a dead horse here but I have a few comments.
1) Crimp, crimp, crimp....
2) 3M seems to make a lot of nice mid-price range crimp connectors. (Digi-Key carries them.)

The nice thing about the 3M ones is they use a soft copper insert inside the crimp that deforms around the wire and grabs all of the strands--they don't leave air gaps and everythign sticks together.

[Glenn Yee Motorsports, LLC]

Solder vs crimp has been a topic of debate for decades. I am hands on and I am speaking from that perspective; by background is metallurgy. I have seen crimp connections fail perhaps 50 to 1 over soldered but that being said, the majority are the type with colored nylon that one uses a $10.00 crimping tool; many are aluminum and will not handle the heat generated by the resistance of a bad crimp. We work with Motec as well and those are only crimped and virtually never fail. Very difficult to solder something that small and still have it fit. Other than for data and 2 way radios, we do not own any crimp connectors or crimp splices. Everything is soldered and heat shrunk. The amount of solder and heat affects the amount of wicking up the wire you get. All battery cables are soldered. I don't know if there is a perfect solution as there is validity to most all stated on this forum, perhaps one consideration should be the use of the connection. At least we can all agree on solder or crimp, this week I saw a loose battery cable that was held in place with 2 bolts and a flat bracket!

[Michael Schwaiger]

I have been to Bosch Motorsport near Stuttgart. They are doing various looms from formula 3 up to LMP series.
They use Deutsch Connectors throughout and dont use a singel blob of solder on the whole loom.

So crimping is the way to go. Every professional motorsport series uses crimped looms, even street production cars got crimped looms.

cheers

Michael

[Buckingham]

Anyone know what they use in Fighter Jets? If it was me, I would copy those guys...

[Peter7307]

Or whatever method was used on the remote vehicles sent to Mars.
If anything fails up there there is no one around to fix it.

Personally I have seen both crimping and soldering done and both both fail.

The quality of the installation is more important than the method used to carry it out.

The same argument applies to MIG vs TIG vs Oxy / Acet welding.
Seen ALL of those fail as well.

Pete.

[jaca]

I'm far from an expert, but from what I've read it looks like a good crimp will be better than even the best solder joint, because of solders vibration sensitivity. Crappy butt connectors done with a $5 crimper are probably worse than soldering. A good crimp requires good tools and connectors - it can be surprising to drop 150 bucks on a crimper (and that's at the cheap end of acceptable), but its a faster and more reliable than solder.

that said, you can do fine with solder provided you know what you're doing - well enough for sae at least, f1 and aircraft... not so much

[carbon_black]

As a general question/rule of thumb - what do the vast majority of production car manufacturers use? (or rather, their suppliers, Bosch, TRW...)

---
Pete Ringwood
UTSM FSAE

[exbaja]

Yea, I know I am a Baja guy...used to be when I was in school but I feel very compelled to answer here.

I used to work for Suzuki's motocross race team. We were in the same building as the Superbike race team (ie. Suzuki Yoshimura racing). I spent a lot of time with their data nerd who also built all their harnesses in my spare time picking his brain for information.

Top tier race teams don't go near solder...at least in the motorcycle world.

He had literally thousands of dollars in crimping tools. The harnesses he built were beautiful. Properly sized shrink boots, proper filler epoxy for terminals to make them weathertight, etc. This guy knows his stuff and electrical failures were a non issue on these bikes.

That being said, unless you are using the specified tool (big $) for the terminal you are using, with the correct wire (both style and gauge), solder is probably the best of the two available evils. Those evils being an incorrect tool/wire, or solder.

If you solder, do it correctly. Proper heat, minimal solder, and crimp beforehand.

Tools are an investment that should last a very long time. I would invest in the proper tools, take care of them, and document them well so their intended and proper use is passed on to other generations of FSAE dudes/dudettes.

IS Motorsport in Indiana has a great supply of tools/terminals for high end motorsport and they are extremely helpful over the phone, will send you samples, etc. I dealt with them when I worked for Suzuki and I cannot speak highly enough about the folks there. They know their product, they can help you with your application, and their customer service is second to none.

Hope that helps and you guys are willing to take some advice from a Baja dude.

[fixitmattman]

Deutsch/Delphi &gt;&gt; Solder &gt;&gt; Hardware store crimp garbage

No matter what method you use proper strain relief connections and consideration of securing the harness against movement at the connection is key. Given that there should be no reason why soldered harness connections should fail at the competition if it's done right.