How To Join Multiple Wires: Splicing | Common Loom/Harness Failure Points [FREE LESSON] 

haha cheers @Ryan! We work hard to make sure things are on point for you guys - Taz.

Well said. I don't do automotive wiring but I do do electronics. I now want to do the wiring for my electronics to this standard lol.

Even if you didn't manage to find this before starting it's great to know it's given you some extra confidence in what you have done 😎 This is actually a module taken straight from one of our wiring courses and Zac will be stoked to see your comment here mate. By nature, he genuinely loves seeing his work help people. Thanks for taking the time to share your thoughts 🤘 - Taz.

Yes the cost is prohibitive to those wanting to learn and create their own looms at home, and even for some small commercial operations - Taz.

Glad it helped and hope the install is going well =) - Taz.

Glad you found it and hope you enjoy getting stuck into the harness build 😎 - Taz.

This article here might help you Jorge -www.hpacademy.com/technical-articles/crimping-on-a-budget-tools-and-materials/ - Taz.

Wire Sizing Chart: bit.ly/3ztFGNi (Note you can also get this from your wiring suppliers) Tools and materials: bit.ly/WiringToolsAndMaterials101 Practical Wiring - Club Level: www.hpacademy.com/courses/practical-harness-construction-club-level Motorsport Wiring Package Deal: www.hpacademy.com/hpa-wiring-starter-package/ - Taz.

Sorry for the slow reply, missed a lot of comments on this one somehow. Wire Sizing Chart: bit.ly/3ztFGNi (Note you can also get this from your wiring suppliers) Tools and materials: bit.ly/WiringToolsAndMaterials101 - Taz.

Here is a good list of motorsport wiring suppliers. www.hpacademy.com/forum/efi-wiring-fundamentals/show/wiring-and-accessories-suppliers-list

Ahh yes sorry about that, managed to fly under the radar. Note this is something that is easy to get from your supplier too, just as this module is directly from our course material we supply it to help people out. Wire Sizing Chart: bit.ly/3ztFGNi (Note you can also get this from your wiring suppliers) Tools and materials: bit.ly/WiringToolsAndMaterials101 Practical Wiring - Club Level: www.hpacademy.com/courses/practical-harness-construction-club-level Motorsport Wiring Package Deal: www.hpacademy.com/hpa-wiring-starter-package/ - Taz.

Check this post out: www.hpacademy.com/technical-articles/course-guide-motorsport-wiring-tools-and-materials-resource/ Will find that and more listed, hope it helps - Taz.

@@hpa101 Thank you.

@@hpa101 I'd like to find open barrel butt connectors that are tin plated. I see BMW has some, but seem to be pricey.

Get in touch with some places on the list linked above. If someone doesn't stock them they might know who does - Taz.

You either have to watch the live webinar or purchase the course to receive those. But since I have done, here it is: www.hpacademy.com/assets/33268f057a/Wiring-Webinar-Materials.pdf? www.hpacademy.com/assets/c08f3ce35e/Wiring-Webinar-Tools.pdf?

You can google for the chart tp find the CMA of the wire you are using. Sorry i don't have it at hand.

@@gabrielnicolau747 Cheers for those links Gabriel, legend

Sorry the comments here flew under the radar, Gabriel is a legend, thank you! I've added them to the description too. Wire Sizing Chart: bit.ly/3ztFGNi (Note you can also get this from your wiring suppliers) Tools and materials: bit.ly/WiringToolsAndMaterials101 - Taz.

Ignore what your OEM does, you can do it better. I have to ask, how many wires do you have that you need to splice and why? I feel like this is probably an issue that you could avoid by looking at the cause and fixing that, however, with some specific information around that we can give a more specific solution - Taz.

@@hpa101 , thank you. Particular case I have is a join in the loom of some older Aprilias where the switched live splits to various circuits. They are joined in one bundle using this type of crimp. One I am retiring for a different engine, and in this occasion I intend to using a larger fuse box with a bus bar to provide the power. Hence avoiding the issue. But others I want to keep pretty standard

Is this an issue you have had or are you just thinking aloud? Let us know and I'll see what Zac can recommend - Taz.

This is a big issue, The center path is always the failure point, in Mobil equipment corrosion will cause failure.

Could this be mitigated with a coating like vaseline/dielectric or liquid thread tape? Possibly contained with a larger sized outer heat shrink. OR a waterproof buss bar (1 in, multiple out)?

@@hpa101 I was just thinking out loud - I since moved ahead working with my harness, and with the multi-wire splices, I heated one to create a "funnel" then filled with a liquid gasket, and then heated the shrink tube entirely, and finished off wiping off the excess gasket that was pressed out.

Wire Sizing Chart: bit.ly/3ztFGNi (Note you can also get this from your wiring suppliers) Tools and materials: bit.ly/WiringToolsAndMaterials101

Yes, Andre also makes fitting circlips look frustratingly/deceptively easy too compared to my blunt meat stick (aka finger) co-ordination 😂 - Taz.

They both have their place and when done correctly obviously neither should fail prematurely from poor technique, however the reason why we don't like to use solder is it adds the risk of failure from vibration which is a risk crimping does not add. With that in mind, and the fact it is easier to repeatedly get a perfect crimp compared to learning how to do the perfect solder it sways the pros for crimping over solder in a motorsports application. For finding and adjusting crimps in your loom, you could also take a step back and address why you are redoing or adjusting your looms so often. It might not be avoidable for your application, or there might be something in the way you plan that could be addressed to help you with that. This video touches on this topic if you haven't seen it already, hope you enjoy it: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-L05Ud8NztZY.html That doesn't mean you can't solder yourself if you want to, but not being blind to pros and cons of any tool or technique is important whatever you choose as we know some people do get oddly passionate on this topic (that comment is for others that might read this too 😉 ). - Taz

Really late to the party here sorry, Element14 is a company we use a lot, but check out the forums there are a number of suppliers listed on there:: www.hpacademy.com/forum/efi-wiring-fundamentals/

@@hpa101 thanks guys.

@@SmitherinesRacing no worries, sorry again for being a casual 8 months late, I missed a ton of comments/questions on this video somehow 😅- Taz.

@@hpa101 all good brother, I learned the best way TBH. I bought all the correct crimps and just finished the coil and inj harness for my 30/26. I have to say a huge thankyou to your team for the professional standard and easy to understand videos. I'm currently hooking up all my indicators etc to the Nexus, such a great journey and learning so much.

My build/car is starting to get attention worldwide, and its blowing my mind haha

Hahaha you do you buddy! - Ben

Insulation* 🤓 - Taz 👨🏻

Ahh yes sorry about that, managed to fly under the radar. Note this is something that is easy to get from your supplier too, just as this module is directly from our course material we supply it to help people out. Wire Sizing Chart: bit.ly/3ztFGNi (Note you can also get this from your wiring suppliers) Tools and materials: bit.ly/WiringToolsAndMaterials101 Practical Wiring - Club Level: www.hpacademy.com/courses/practical-harness-construction-club-level Motorsport Wiring Package Deal: www.hpacademy.com/hpa-wiring-starter-package/ - Taz.

@@hpa101 thank you

Indeed! I'd be even happier with four haha - Taz.

I will use a crimp splice then solder and heat shrink

These were (are?) used in factory wiring looms, at least from what I've seen of some 90s Japanese cars

You all seem to be under the impression I was against crimps🤔which is hilarious! I was merely commenting saying there would be people arguing against crimps not that I don’t like them😂 I am not new too wiring or crimps, but thank you👏🏼

Think you just read that into the responses, no one mentioned it

That's pretty much the result I get as well, but mine looks cleaner. You see, I bubble the insulation using my soldering iron and end up with a sanded aluminum look on my joints. The heatshrink however, I brush it with the flame of my bic lighter using the fast back and forth method in combination with a twisting motion while held at a 45 degree angle. As soon as the heatshrink stops moving, remove heat so as to not singe the heatshrink. Then go over it for another ten seconds using the bic lighter method again to be sure you got all the shrink out of it.

@A. Melbs Lol. I don't even remember leaving this message. I must've been messing around. I use a heat gun on my heatshrink. However, when I first started soldering, I used to apply heat too long which resulted in melted insulation. I've honed my skills over the years but thanks for the tips. I do occasionally use liquid tape if the heatshrink or insulation gets damaged. It is good for a quick fix.

I do this pretty much exact technique often, never had any issues.

@@allenkilpatrick7701 i never experienced any issues... or the fires or deaths they warned me for xD

What scares me is the little plastic colored wire crimps that some manufacturers recommend using!

@@allenkilpatrick7701 OEM wiring scares me all day.. my misses her ride had a problem where the wires to one of the doors were to short.. and they shaved trough! happy days!

I have some horror stories for sure. Like the wire insulation being soy based. Basically a hot meal

try amazon or ebay man

@@lockya4128 Ended up buying about 5 different tools. This is the best one I found for the price www.amazon.co.uk/gp/product/B078SQXZSQ/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

Thanks for sharing @Guy, this one still going strong for you? It is a bit of an investment to get setup, but it's always cheaper than paying someone to do it for you (not accounting for time) so long as you do use the right tools and materials to do the job correctly 🤘 - Taz.

You are free to do this, but really if you feel the need to do both you're either doing one or both techniques incorrectly - Taz.

No No, I respect that opinion but com across so many manufacturers connections that have failed, and its corrosion that affects the joint that solder would prevent

Solder is not immune to corrosion, it is only more resistant. A poorly sealed solder joint will also corrode, so while you might feel that adding the solder is helping avoid one issue, you are still potentially creating another arguably greater risk. Arguably is where things become murky for most, but we're not telling you what to do yourself at all, just trying to arm you with a bit more knowledge. I do understand the logic though and you're not the only one to mention this often. I would take a close look at the connections you see that are failing due to corrosion as I'm sure you will find that the crimp itself isn't actually the problem but rather the sealing around it that is no doubt poor or has failed is. That said, we are talking motorsport wiring, and generally what you're doing here is going to be better than OEM production vehicle wiring when done correctly - Taz.

You can do what suits you best, but we 100% so not advise soldering your crimp joins - Taz

Can advise what you want but I've never had a failure

@@anythinggarage9602 You might not of had a failure, but you've introduced more of a chance of having one. Again, you're free to do what you like on your own builds, but there are pros and cons for everything you do. Whether you want to accept it/educate yourself or not that's up to you, but it doesn't change any facts =) There is plenty of material out there on the pros and cons of both soldering and crimping, and also why you shouldn't do both if you're keen to learn more, otherwise happy wiring with what you're already doing but we just advise anyone reading your comment does their homework before blindly soldering AND crimping everything thinking their doing the best job they can - Taz.

@@anythinggarage9602 Space industry use crimping and soldering, so you are right to do so.

We're just going to steal his glasses and blind him instead, job done 😅 - Taz.