Why does nobody use motorbike bullet connectors?

Oh really? I didn’t even know about it, I though automobile’s stuff are definitely stronger then hobby’s… appears that I was wrong lol

stuff used in the automotive industry it actually quite rubbish in comparison to the hobby RC industry. it just doesn’t need to be as hardcore.

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Wow that’s intense to me…first heard. now I get it:wave:

Strange, my local Island sparky who runs his own business doing solar installations (on and off grid) keeps telling me I should get a good crimp tool and go with a gas tight crimp as they never fail and the wire remains flexible…

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Soldered wires remain flexible if it’s done correctly. Soldered wires will have less resistance than crimped wires. Soldering wires for a solar installation would not be practical and crimping is good enough for that scenario.

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an off grid install has a bit more to it… he builds batteries systems among other things. I’ve tried a google and eSk8 search, can you point me to a table that lists relative resistance for each?

@deucesdown seems to agree…

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I don’t know of a chart that compares the two. It just makes sense that a soldered joint will have less resistance and will not work loose from excessive vibration.

Is there any data to back up this statement:

A gas tight crimp is optimal and is what’s used in extremely high current situations like sub stations though that’s mainly because the wires won’t be taking much stress and the wires are often so thick you can’t solder them. Personally I never trust a crimped wire to tension like trying to pull it out, I’ve had many crimps come un-done and that’s why I like to solder. Especially for eboards where your often plugging and unplugging wires I’d recommend soldering by far.

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I did a forum search on “crimp” & "solder and not much came up, the aforementioned quote was as close to data or another opinion as I could find :disappointed:

Ok, well I don’t have any data to back up my claim either. I’m just trusting my gut on that one. It would be interesting to solder a couple wires together and crimp a couple wires together and test them with an ohm meter. But then the results would depend on the quality of crimp connectors and crimping tool. And if the wires where tinned or just twisted.

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thanks Nama,

agreed :wink:

Properly crimped connections are better than soldered connections. In a properly crimped connector is gas tight, this means that there is no gaps between the connector and the wire, leading to what is essentially a cold weld.

Solder itself usually has higher resistance than the copper wire and the plating on the connector, therefore any solder in your joint has higher resistance than the equivalent crimp.

Solder also wicks up wires. Making them less flexible and more brittle. A gas tight crimp does not have this issue and is several magnitudes more reliable than a soldered joint.

This is what is taught in school and the reason why the industry standard is to crimp connectors.


Quality crimping tools can vary in price between several hundreds to several thousands.

Just for reference, the cheaper hand crimp tool for JST XH connectors on batteries costs $490, while the more expensive one costs $1057 on digikey.

And those tools can only crimp XH connectors. If you want to crimp a JST PH connector, you would have to buy another $1057 crimper that only works on PH connectors.

There are crimpers that use dies but they run in the $4-5k range and each die set is roughly $500.


Your $20 hobbyking crimper is never ever ever going to produce a crimp of such high quality. At that point, yes, soldering is better.

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what do you think of a hydraulic crimp tool with dies like this?

using wire… to suit

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Awesome post.

I’ve done an embarrassing amount of reading about crimp vs solder, and you said it better than I ever could.

Just to fill out some details (disclaimer, this is based on stuff I read, not experience), solder wicks up the wire under the insulation, not necessarily visible to the eye, and embrittles the otherwise flexible copper wire. In a high vibration environment this leads to wires breaking.

There also seem to be issues with solder in corrosive environments.

Another factor is solder melts at high temperatures. This is kind of extreme, but it could make a difference in certain connections.

For marine applications, crimp terminals can be had with heat shrink tubing that has hot glue in it, for waterproof connections.

If you look around in cars, airplane, motorbikes, even factory machinery, no soldered connectors.

I’m not convinced hand crimps are necessarily worse than soldered. Quality will vary like crazy, but with knowledge and the right equipment, you have a chance of making good crimped connections.

I think some people who’ve been around the block will crimp, then apply just a bit of solder to the cut end of the wire.

When I started getting serious about doing a build, I was convinced I’d use Anderson Powerpoles. I kept reading and reading, and the variability of the quality of crimps lead to too many stories of failures. I’m mostly using Amass branded connectors, XT150/XT90/XT60/bullets. (I love the euro bullets @Cobber found, but $$$ and a pain to get ahold of?)

I also looked into screw terminals and bare wire (phoenix terminals?), looks like crimped ferrules is better than bare wire, and soldered is plain bad there.

I’m still rolling around in my head having bus bars in the board, with screw terminals, and all wires have ring terminals.

This link does a good job of talking about the details of crimped connections.

And same guy ranting about a failed soldered connection:

And @Cobber dragging me into an argument? :slight_smile:

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Those are so cheap on ebay! I almost pulled the trigger many times. I think overkill for our 12/14/16/18 gauge wire though.

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@Cobber @deucesdown I’ll be completely honest and say that I have never crimped anything larger than a 20awg wire. I haven’t even looked into the appropriate tools for that. I enjoy soldering.

Only crimp I have seen with wires within that size range is a $20k 20 pin circular connector on a part from Boeing while I was at NASA. As far as I know, each bullet cost something like $100. The crimp tool had a dozen or so teeth that came out perfectly in sync and crimped the barrel perfectly onto 12awg wire.

So I honestly have no idea on what tools or crimp connectors we would use. The only ones I use regularly are JST or Molex crimpers on small wires.

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I love crimping my own perfect length balance leads :yum:

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Holy sh…! I hope he keeps that pegboard behind bars and an iron curtain. Some really really expensive tools on it!

anytime dude :thumbsup:

yeah, Specs: Max Working Pressure: 10 ton Maximum Working Stroke: 10mm Crimping Die Qty: 9 pairs Crimping Type: hexagon Die Size: 4, 6, 8, 10, 16, 25, 35, 50, 70mm²

& agreed, the marine heat shrink looks nice…

check these high amp antisparks, I’m getting some of these to go with. Think they are US made so you might be able to find a deal? https://www.hyperionaustralia.com.au/store/Anti_Spark_conectors/Jeti_Anti_spark

I’m thinking I might try to crimp (the splice of) the backbone of my new loom (6awg).

my biggest hate with lipos! always uneven :rage:

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http://amzn.to/2AmNJgf http://amzn.to/2CgN4OO

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