Best way to take branches off fround and power wires?

Wiring best practices and loom building technique
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Basil
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Joined: Fri Sep 16, 2011 2:28 pm

Best way to take branches off fround and power wires?

Post by Basil »

Let's say I am trying to take a wire from the ecu sensor 5 volt supply out to six sensors. How would the pros splice 5 branches off the main conductor, all from one place (bulky, and how to splice 5 conductors to one main one?) or several branches spaced according to sensor position along the main conductor. Do you, in the latter instance, cut the main conductor at every branch, or carefully trim back insulation and use tiny open sided C crimps like the OE automotive looms on Jap cars seem to do? Where can you buy the little open sided C crimps and a suitable crimp tool? Thanks.
x30xe
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Re: Best way to take branches off fround and power wires?

Post by x30xe »

This is good question. I would also like to hear answer. It is so dirty, ugly and unreliable to cut and solder joints even they are later covered with heatshrink tubing.

I've heard that some source sells some generic "splicing" connectors, was it Motec or Haltech. There must be a professional level solution for this !
Jon K
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Re: Best way to take branches off fround and power wires?

Post by Jon K »

BMW does it this way, and I have done it this way on my recent re-wire - its called a lash splice:

Image

You guys should check this thread:

http://dtaforum.com/viewtopic.php?f=9&t=10

I also use a barrel sleeve so its basically the metal barrel from a ring terminal, crimp it, solder it, cover it. They have varying sizes you can run.
1992 700RWHP Pump Gas BMW
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stevieturbo
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Re: Best way to take branches off fround and power wires?

Post by stevieturbo »

You dont need to join them all at the start. Just as and when you need to.
And crimps are always the best solution. ( non solder crimps )
Although by far the easiest for most is to solder. Just ensure the wires are properly supported afterwards so they can never fatigue and break.

Also see here

http://www.pistonheads.com/gassing/topi ... sting+Loom
VR6Turbo
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Re: Best way to take branches off fround and power wires?

Post by VR6Turbo »

Yep, VW use those hot glue in-line splices.

For example, in an injector harness where 6 injectors share the same 12V but the wires for each injector are different lengths, they bundle 3 powers together in 2 places along the length of the harness, then 1 single, larger diameter 12V wire goes off to the fuseboard.

As Stevie said, soldering is as good a method as any though.

Some of what OE makers do is done out of ease of manufacture. Their looms are mass produced on peg boards and time is money!
Basil
Posts: 36
Joined: Fri Sep 16, 2011 2:28 pm

Re: Best way to take branches off fround and power wires?

Post by Basil »

As an aside I saw someone connecting a triple core screened cable to a flying hall effect sensor lead using these little devils. I will be ordering some today, and the tool, splicing screened leads has always been a PITA before I saw these!

http://raychem.te.com/documents/webserv ... &docId=923

Edit:

Bit of luck, found the tool on Ebay USA for very sensible money, and it does all the Miniseal crimp range :) I have found once you use the right crimp tool generic ones never seem the same, shame all the decent used MIL spec tools seem to be in the US.
Last edited by Basil on Mon Sep 19, 2011 5:27 pm, edited 1 time in total.
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ignitionautosport
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Re: Best way to take branches off fround and power wires?

Post by ignitionautosport »

stevieturbo wrote:You dont need to join them all at the start. Just as and when you need to.
This is true, but for ease of servicing all joins are at an end connector in my harnesses, so I never have to repair a break mid-harness. Rare for it to happen, but nothing worse than having to undo half a DR25 harness to re-heatshrink a join after you have repaired it..
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stevieturbo
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Re: Best way to take branches off fround and power wires?

Post by stevieturbo »

If you have the room for the extra wiring bulk, then yes making joints at a convenient single location can be best.

But to streamline and thin a loom, joining only where necessary also works great.
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