Cable connectors at sea

MM5AHO

MM5AHO

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This winter I'm planning to rewire the electrics in our Rival 32.
About every two years I replace a "chocolate block" type cable connection block as it corrodes.
Is there a better way to join a bunch of cables (single conductor, multi strand copper, plastic sheathed) similar to such a connector block without this issue?
Does anyone make a stainless and plastic one? (Most seem to be zinc or nickel plated steel.)
 
MM5AHO said:
About every two years I replace a "chocolate block" type cable connection block as it corrodes.
Is there a better way to join a bunch of cables
Click to expand...

Yes!

Personally I favour soldering then covering with adhesive heatshrink (which also provides strain relief), but others quite reasonably prefer crimped fittings.

Pete
 
Grease filled crimps or connectors made by 3M or Dex. Probably get them on ebay or maplins. They are permanent though so if they ever need to be removed you need a bit of spare in the cable to cut them off and reterminate
 
I never use chocolate block onboard. It is (IMHO!) the work of the devil. I solder and heat shrink or use the gel filled connectors that Spyro suggests.


Although I guess, if you really want to use choc-block, you could try filling the spaces with Contralube (see the other thread), that would help, but I don't think it would completely fix the problem.
 
Im not a fan of choc bloc connectors - most are prone to corrosion and all are fiddly to connect. Soldering and heat shrink have their place but some kind of terminal block is required. I've seen some overcentre type clamps on CPC site that look promising. The advantage is that no screwdriver is needed for the final connection.
 
I use crimped on car-style bullet connectors for my mast wires as the mast comes down every year. The connectors are all down below in a small tesk-fronted box and my thinking is that the action of pulling apart and reconnecting will scrape off any corrosion that develops. It's worked for about 3 years so far.
 
I, too, avoid chocolate block, but have a legacy one (well protected from the elements) which connects very fine instrument wiring - which seems suited to the kind of connector used with telephone cables. I have had no problems with it, but feel I ought on principle to replace it. I hope the OP will forgive my using his thread to ask what would people recommend for such fine wiring?
 
If choc blocs are corroding that badly, your boat is quite damp.
I got conned into helping with a temporary fix on a friend's MAB 'to get to the end of the season', I think it was the 2008 season but it's still all fine, as I noticed when I got conned into adding something else.
I'd used Screwfix's finest choc bloc, £1.20 for 10 strips or something, and a quick squirt of GT85.
 
MM5AHO said:
This winter I'm planning to rewire the electrics in our Rival 32.
About every two years I replace a "chocolate block" type cable connection block as it corrodes.
Is there a better way to join a bunch of cables (single conductor, multi strand copper, plastic sheathed) similar to such a connector block without this issue?
Does anyone make a stainless and plastic one? (Most seem to be zinc or nickel plated steel.)
Click to expand...

Larger choc blocks (e.g. Maplin 35A) have M4 screws. Smaller ones have an unidentified thread. I replaced the M4s with A2 grubscrews and tapped out the smaller ones with a cordless drill to accept the same.
No corrosion so far.

I like choc blocks because they allow flexibility, can accept several cables and are a boon for fault tracing. My cables are terminated in "bootlace" crimps (narrow long ones from RS) and are colour coded back to source.

Mind you - I like complication!
 
nigelmercier said:
Depends it you need to undo it.
No: solder with adhesive heat shrink, either inline or side by side (better).
Yes: a proper connector block with screw terminals, ring terminals on the wires.
Click to expand...

Thanks Nigel. I'd believed that the smallest crimp ring terminals were the red-coded ones (for 22-16 AWG), but your reply prompted me to look further and I see that there are green ones for 24-20 AWG, which I had not encountered before.
 
Hydrozoan said:
I'd believed that the smallest crimp ring terminals were the red-coded ones (for 22-16 AWG), but your reply prompted me to look further and I see that there are green ones for 24-20 AWG ...
Click to expand...

I didn't know that, got a link? I guess you need a different crimp tool.
[Later] Found a tool: http://www.ebay.co.uk/itm/350670540673

I normally just double the end of the wire over.
 
Last edited:
Graham_Wright said:
…… My cables are terminated in "bootlace" crimps ….
Click to expand...

I have often seen these in catalogues and I wondered what they were specifically for. I assume the bootlace is best used with the type of choc bloc that has the plate beneath the screw to clamp the boot lace.
 
nigelmercier said:
I didn't know that, got a link? I guess you need a different crimp tool. I normally just double the end of the wire over.
Click to expand...

This is just the one I came across, and I don't know how readily available they are in small quantities - and yes, I guess one would need a different crimper.
http://www.cable-jointing.com/sites/default/files/products/cembre-crimp-terminals-pre-insulated-halogen-free-vp-rp-bp-gp/Cembre-Insulated-Cable-Crimp-Terminals-Halogen-Free-VP-RP-BP-GP.pdf

I suppose I could just double over but part of my tardiness in doing it has been that there's not a lot of spare cable (and it's not very easy of access) - coupled with the fact that it's well protected and has worked without a hitch for >10 years. But as I've updated pretty much all the DC stuff, I keep thinking I ought to tackle it. :(
 
I have a plywood board that covers the various electrics and the back of the cockpit mounted tacho, and engine controls board (which faces out toward cockpit)
This board currently has a small panel of 7 switches and 7 fuses. I intend to make anew one of these and mount the enlarged panel in the same ply panel.
The panel fits into the top step of the companionway.
The boat is 40 years old (Rival 32), so can be a little excused for slight dampness I think.

The reason for having some form of connector is to enable the dismounting of this board in winter for engine maintenance.

I had also though of a socket and plg, using perhaps a 20 way plug or so to allow for any expansion.

Current switching doesn't cover all it needs to, and I want to expand this. For example current nav lights arrnagement (possibly original) is wrong in that steaming light comes on with nav lights. That's not right when sailing at night!

The current choc block has lasted perhaps 3-4 years.

Thanks for the various suggesitons.
 
For that purpose I think you could use one or two of a product named SureConnect2, found on this site:
http://www.mitron.se/
It combines the function of choc block and connector. Have not used myself, but other items from the same source – good stuff.
 
BabaYaga said:
For that purpose I think you could use one or two of a product named SureConnect2, found on this site:
http://www.mitron.se/
It combines the function of choc block and connector. Have not used myself, but other items from the same source – good stuff.
Click to expand...

That looks suspiciously like the one available from Index Marine in the UK, see the link I put in post #2.
 
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