connect wires
 

I need to replace my bilge pump which means connecting the 12 inch pump wires to the boat wires which are wrapped inside spiral wrap above the deck before all the engine wires go through a gator under the deck, so do i solder the wires then shrink tube before replacing the spiral wrap or do i just use shrink crimped connectors, and are the halfords ones ok or are there special marine crimp connectors?

solder it then shrink wrap crimps will corrode two different metals in contact will always corode where they touch even if you keep water out

Use glue lined heatshrink connectors. Soldring is a bad idea on something right next to the bilges.

Use decent quality ones-the ones from Vehicle Wiring Products for example are tinned copper, so you won't have corrosion issues.

Thanks i got those shrink crimp connectors today from force4 and new pump so will fix tomorrow with my new crimping pliers, might be doing in the rain though!

Which 2 different metals? Crimps are copper, as is the conductor in wire.

In any case, you won't get dissimilar metal corrosion unless you have the joint submerged in saltwater (and if you do, your wire isn't going to last long anyway.)

jky

Now being an electronics engineer i find this odd.....

We Always Solder then 2 layer of glue lined heatshrink been doing this for years 40 + and never had issues, It is a MoD approved way for numerous projects that I have worked on as an electronics engineer.

Glue lined heatshrink crimps give the joint mechanical stability plus seal the joint from the outside environment. As does Ashbypower's method below.

The reason I gave the OP the reply I did was because it's the easiest,quickest most secure way to do a pretty grotty job in an area that'll already be contaminated with salt and dirt.

You shouldn't have any corrosion problems as long as you solder using "Electrical Rosin Core solder" and that if properly sodered, each solder-joint must shine to almost chrome looking. Then, bypass using Heat Shrink Tubing as you want to make each finished connection Air-Tight. The best way I have found to do that is in using a "Liquid electrical tape" in two-three coats. It will insolate and waterproof each connection. There will be no corrosion as NO AIR can get in to the soldered joints.

A crimp joint using the right tools will usually be better than a badly done solder joint. All-in-one adhesive heatshrink crimps plus another heatshrink tube if you want belt and braces. Re comment about corrosion, the adhesive should squeeze out the air.

There's a line of thinking that solder can wick up the wires in the cable. This can make it more prone to failure if there is insufficient support around the joint.

Soldering is always best, especially for conductivity..kinda-like when crimping your connecting one length of good wire by the hairs to the next..goodness that's why the arching/shorting. But you must practice before soldering and it takes a bunch of practising. But as I said before if the end product is a Chrome-like solder, you got-it!
Twist the two joints of copper wire together (tighter the better). 2): Using your electronics soldering Iron, heat BOTH wires hot--then!, allow the touch of the solder in the middle of the joined connections be ABSORBED into the joint..you'll see it being absorbed. If your lead(s) are close to electronics use the aluminum heat-shrink clip to keep the wire coller heat beyond the joints your soldering. NEVER USE CRIMPS. In the case of pre-crimped things such as 6-8 gauge main battery -- starter motor or solenoid connectors. HEAT THE COPPPER JOINT super-hot, applyt the rosin core solder and watch it get absorbed between the copper cable wire and crimped copper sleeve! Now you have seriously increased Amperage flow capacity. Trust me, have been doing it in the Marine field for many years. You will, if sealed correctly ("Liquid Tape") to keep both air and salt OUT you will never have trouble due that joint again, ever.

Seems some anti solder bias on this thread which i cannot figure out. I don't do marine electronics but do electronics and once soldered a good solder joint is very unlikely to fail. Heat shrinking is good but potting is better. Potting Compounds and Encapsulants - from INTERTRONICS

I thought my post indicated why it's not necessarily the best solution.

'Electronics' are a different matter to the wiring on a boat. Electronics will usually have single core wires used in a stable environment whereas boat cable is stranded for flexibility and vibration resistance. A crimp connector automatically provides support to the cable away from the joint.

Soldered joints are specifically not recommended by US ABYC. I believe also avoided in aircraft. So I don't agree that 'soldering is always best'. Not sure that potting is very practical if you have lots of connections to make.

Usual advice for crimps applies - use a proper ratchet crimp tool (not the pressed steel Halfrauds jobs) and quality tinned copper terminals with heatshrink insulation (these tend to be better quality anyway). And spend the bit extra for tinned cable. People swear their ordinary copper is OK but I've seen plenty of corroded cables even on relatively dry boats.

The company I work for hire diver operated dredge systems which employ a large 440 v motor on the seabed fed by a 300m umbilical
All joints are soldered then potted & we haven't fried any divers yet
The solder provides a water block at the joint which prevents water tracking up the cable if there is water ingress on one side of the joint
These work in 200m of water 20bar of pressure life threatening voltage & are reliable
I'm sure soldering is good enough in the confines of a boat
I'll stick to soldering mine anyway

:thumbs:I'm a big believer in WELL soldered joints + Adhesive lined heatshrink. The secret is, make sure that the heatshrink extends well past the rigid soldered section of joint onto the flexible portion of cable, either side of the joint. In a previous life I was an electrician in the mines, soldering & taping was always the method of choice for cable jointing when circumstances permitted it. This was used in everything from 6.6kV feeder cables to intrinsically safe signalling systems. The underground mining environment was about as harsh as it gets; wet, rough abuse, hazardous atmosphere, vibration etc.

As MikeCC said, the American Boat and Yacht Council discourages soldering:

Follow the ABYC Standard in Electrical Wiring and Connections | SailAngle.com

Look for the paragraph starting with "Another common misconception dictates"

I'm not saying that soldering won't work (and in truth I have quite a few solder butt joints in the wiring on my boat); I'm simply laying out the why's and wherefores.

jky

Erm hardly, wiring looms on cars, planes helicopters all get soldered. PCB are all soldered. Perhaps your soldering just isn't very good?

good info on soldering for aircraft here. https://www.casa.gov.au/wcmswr/_asset...21c99s2c07.pdf

Very very rarely do we use solid core cable the exceptions being RG and other coax (rarely soldered) and infrastructure data cable (never soldered) stranded cable is the type normally used for soldering.

Oh and in military vehicles all the connections to the loom plugs are soldered (these are vibration tested to incredibly high levels (so high the bits of kit they plug into have to be installed on "shock mounts")

NASA also solder wires Guide on how to splice solder single core wire to NASA standard. How-To: Splice Wire to NASA Standards | MAKE


If the cable is critical (safety or otherwise and is damaged the whole cable should be replaced.

On a side note my washing machine has just been repaired after the "red wire to the heating element came out of its poor crimp and was loose in the casing (it was also to short from the factory)

A bad joint is a bad joint, a good joint is a good joint but i would rather a good solder joint over a crimp.

I don't remember too many solder connections in my Toyota 4-Runner. Haven't really torn apart the wiring though.


Not on the tactical avionics I used to work on. Connectors were mostly crimped on I/O connectors (those external to the box.) Internal connectors were soldered or not depending on the connector specified.

I don't recall any butt joints in use - every wire terminated on either a connector or a PCB pad.

Yeah, and getting NASA certified to be able to solder for Space Shuttle stuff was a genuine pain in the ass. Stranded wire solder joints were all inspected so as to not have any solder wicked up the conductor.


jky

Wouldn't expect any less to be honest.

I worked for Caterpillar for years and I can confirm that non of the connections on the machines we built were soldered, except on proprietary items (e.g. internal connection on bought parts). Experience over 80 odd years showed that solder joints were more prone to fatigue failure than crimp joints as the cable becomes stiff and brittle. All cable connections were made using very high quality plugs/sockets with crimp pins and rubber seals or well heat shrunk crimp connections. They weren't typically submerged but regularly pressure washed. I am pretty sure that most of my cars have been largely solder free also.

I've never had either fail though so this is only an observation.

Phil M