Dull wiring question

Fascadale

Fascadale

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I am now beginning the lengthy journey towards mastering the secrets of tinned wire, terminations, butt joints and crimping. ( largely thanks to brilliant websites like this )

My next question is what is the best way to join three wires? I want to do this away from any junction box. Is a "piggy back" the way to do this? It seems a slightly fragile way to do it. I have not managed to track down any heat shrink piggy backs like these spade/blades

Any suggestions?
 
elton said:
Scotchlok connectors are designed specifically for joining 3 wires. As long as you use the right size connector for the wire you can't go wrong.
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Scotchloks are designed to attach the end of one wire to the midpoint of another, which is not quite the same thing. They are also a god-awful bodge which should have no place on any respectable wiring system.
 
Ubergeekian said:
Scotchloks are designed to attach the end of one wire to the midpoint of another, which is not quite the same thing.
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Quite true, but two Scotchloks can be used to join three wires.

Ubergeekian said:
They are also a god-awful bodge which should have no place on any respectable wiring system.
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Would you care to elaborate? I'm sure 3M would welcome your feedback.
 
elton said:
Quite true, but two Scotchloks can be used to join three wires.
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Bodgier and bodgier!

Would you care to elaborate? I'm sure 3M would welcome your feedback.
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Like gaffer tape they make a perfectly acceptable quick fix but not a good long term solution. For a start they are almost impossible to seal effectively.
 
Ubergeekian said:
Bodgier and bodgier!



Like gaffer tape they make a perfectly acceptable quick fix but not a good long term solution. For a start they are almost impossible to seal effectively.
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Nothing like gaffer tape; the blade embeds in the conductor, which is how all crimped crimped connectors achieve a permanent join.

I would solder and use heat-shrink sleeving, but if soldering skills are limited, a Scotchlok connecting would be a satisfactory alternative.
 
As an alternative to the type of Scotchlok connectors suggested already consider THIS TYPE

Can accept several wires
Perhaps more easy to seal
Perhaps a better connection between the wires for good current carrying capability.
Perhaps a better choice if there will be any future requirement to remove.

For a water proof connection use with the Direct bury splice kit


Otherwise for three separate wire ends use the "pig tail" type connector rather that the "runtap" or "T tap" types
SEEthe video here
 
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Elton

I do not know of a proper crimp connector that has a blade embedded in a conductor. I wouldn't use them on a boat and have never seen them on a boat with well done wiring.

A proper crimp will form a cold weld over a much larger area than a blade ever could, as shown in the first link in the first post.
 
Many years ago between University and College courses, I had a year out and worked as an Auto-Electrician. Scotchlock connectors were commonly used in car electrical add-ons in those days and if we got a vehicle in with problems, they were one of the first things to check.

Although some may have examples of such connections lasting for years, I would find no place for them on our boat. If I found any, I would be replacing them very quickly. (But I know there aren't any as I have been through all the wiring pretty thoroughly...)

Use proper crimp connectors with a decent crimping tool.
 
Raymarine include Scotchlock connectors as standard in some of their kit. I installed a C70 plotter on Deep Joy the year before last and the connections for the new Raystar GPS antenna were Scotchlock. On passage after fitting, the C70 lost GPS data, and I ended up in Padstow replacing the Scotchlocks with chocolate block connectors. I wouldn't use Scotchlocks for anything again, and would not recommend them.

To join 3 wires, I would twist two of them together and crimp into one part of the connector and crimp the other wire into the other half. You can use a larger wire size connector half for the pair which you have twisted together. I prefer bullets to spades.
 
if you need to do it properly, (i presume for power) then crimp a round crimp to each wire and then screw onto a small busbar which you can install at an appropriate place for your installation.


For data i use 2 and 3 idc connectors for the small cables to connect some instrument wires as it gives better connectivity then the choc blocks, and if there good for broadband there good enough for the boat.(not used everywhere, just one place in a junction box where they were more suited then a choc block connector).

http://cgi.ebay.co.uk/3-WIRE-TELEPH...0111113469&po=&ps=63&clkid=565448628585844932
 
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elton said:
Nothing like gaffer tape; the blade embeds in the conductor, which is how all crimped crimped connectors achieve a permanent join.
Click to expand...

Crimped connectors make a cold weld (continuous metallic structure) between the conductor and the terminal. Scotchlok do not. They are Insulation Displacement Connectors (IDC): the blade cuts the insulation and the conductor is forced up into the slot. Connection is by contact only and therefore susceptible to corrosion at the interface, particularly in damp environments. Crimps don't have that interface.

As I said, Scotchloks are perfectly acceptable for a quick fix (I've used 'em myself), but long term use is a dead giveaway of sloppy standards.
 
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Scotchlocks AGGGHHH!!

Only cowboys use scotchlocks

PLEASE !! Use ring crimps and a bushbar if you dont want to be chasing intermittants problems around for your boats for years to come.

Also a good investment is a ratchet crimp tool ,it takes the guess work out of crimping correctly
 
I used to use scotchbodge and chocolate bodge when I was 17 on my car stereo's.

Then I did an aircraft maintenance engineer apprenticeship.

The first thing I did when bought my current boat was to go through the entire vessel replacing every bodged connection with proper, ratchet tool installed crimps. Yes, unbelievably Princess used chocolate blocks blxxdy everywhere!!

No, no, no, no!!

Crimp.

As posted above, ring terminals and busbars for multiple connections. Or Burndy blocks, if you have aircraft grade money!!
 
Would anyone care to explain the difference between the connection achieved using a Scotchlok, and that of a crimped IDC? Or pehaps provide a reference. As I understand, they are both IDCs, so would have exactly the same mechanical, chemical and electrical properties if properly fitted.
 
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