Wire nuts

RC
You demonstrate an understanding of how over bearing we can become. We sure did hi-jack Joe's post!

On the wire nut thing. I'm going to repeat others comments, but I remember years ago watching the solid strand copper wire being twisted together in the proper direction and then the nut "screwed" on. Very often taped after the fact. And these were land side applications. Stranded wire which was develop to allow more pliability in the wire run, but just doesn't accept those "nuts" as well. Pouring epoxy or silicone into the open side only interferes with conductivity, imo., and is an admission that the "nut" is not a proper connector on a boat.

Recreational boating is conducted in a harsh environment, so take the time to do the best repair/installation that makes sense.- on any repair. For goodness sakes you're out in the bay or the sea probably with your family. Failures in an inlet can be bad (remember Mr. Murphy?) IMO, as supported by ABYC and others , stranded wire should be connected with a soldered joinder or a mechanical crimp (if you fish you know how important that is on braided wire) Then cover the connection with a marine shrink wrap material - and go that little extra distance, its inexpensive compared to a failure. If you want to put a little silicone around each shrink wrap end, that's not bad either. It adds to the strength of the connection and reduces permeability. All marine wiring should be supported at reasonable intervals to prevent stretch, tension, and keep it out of harm's way.

This is all aspirational, of course. If you have to get home or take the in- laws out for lunch, sometimes a bobby pin in the right spot works too?

I think you were all just advising on things he was considering that you would not recommend. As to the various forms of connecting wires that some would use, many are not appropriate even on land in a far more protected environment. While the odds are very much against having a problem, we still do see a lot of land based electrical fires and most are the result of short cuts taken.

What is "too large"?

What size should a butt connector be when used that way?

Should a butt connector be used that way?

Ideally, no it should not be used that way. They are designed to have 1 wire of the proper size of the butt connector in each end to gain a positive crimp and seal on 360 degrees of the wire end. I've seen 2 16 gauge wires crimped into the same end of a 12-10 gauge heatshrink butt connector and the other side left open in a wet location like a bilge pump. Heatshrink wouldn't seal the open end and etc. Instead of using a 14-16 gauge butt connector with 1 wire in each end and crimped. There are a lot of ways to do something like an island engineer would and half the time they're acceptable, but are they really right, no. I don't do things unless they're done right.

I choose to do things the best way for the job that looks and is like something a good manufacturer would do and meets ABYC and USCG standards. I do things textbook so that nobody can come back after me and say "why did somebody do it this way." I take pride in the mechanical work that I do. Just like I always use AWAB hose clamps instead of those crappy breeze ones on all of my customers boats. Are they acceptable, yes, do breeze clamps last more than a year or two near the bilge before breaking in half, no. Just like I always use manufacturers filters and parts instead of Napa/WIX/Fram etc. etc. Nobody can fault you for an oil related malfunction on a CAT that has a CAT oil filter on it and the proper level of CAT oil in the pan.

Wire nut or not? http://www.idealind.com/products/wire_termination/lugs/set_screw_connector.jsp

Two wires in a butt connector?

Or like NASA (talk about heat/cold/corrosive atmosphere/vibration) does it ...

https://standards.nasa.gov/documents/detail/3314921
http://workmanship.nasa.gov/lib/insp/2 books/frameset.html

I use uninsulated connectors for all connections that require butt splices and also use uninsulated ring terminals then heat shrink after crimping.
http://www.digikey.com/product-search/en?FV=fff40016,fff800b6,ffec52b0

If the wires may need to be separated regularly for service then use aircraft grade knife splices covered with clear heat shrink.


The quality of crimpers available for uninsulated connectors is generally far better (expensive but worth every penny) and the ability to easily verify crimp quality is priceless. They are available for wire as small as 26AWG and if used in wet locations should be covered with adhesive lined heat shrink, use regular heat shrink in dry locations.
http://www.newark.com/heat-shrink-tubing-adhesive-lined/prl/results

For bilge pump and float switch connections on small boats (that are seemingly always in need of replacement) I use a small non metallic enclosure of the type made by Vynckier http://www.vynckier.com/ with a Euro style terminal block inside to make the connections.

Euro style blocks make the connections "touch safe" and are far more reliable than the open screw style. In critical applications I use crimped insulated ferrules to eliminate the risk of stray wire problems. Again, the crimper for these is expensive but the results are priceless. Wiring into and out of the enclosure is by way of plastic cable glands to assure a water and vapor tight seal. Think about the next guy who has to replace the pump or float switch, leave a wiring diagram in the box before closing it up. Connecting a bilge pump/switch in any other way is, in my opinion, less than professional and makes servicing far more difficult in the future. That is what always leads to the kind of redneck wiring that is so common on small boats.

On my last boat the high water alarm was connected to a $9.95 car horn. VERY loud, and audible over the entire boat, with engine running.

Just tried these on a switch in the engine room. They are supposed to be waterproof.
They worked as per the description on the packet. Shrunk very tight and the solder melted on the inside, onto the overlapped wires.
No crimping needed. Just heat.

The first try didn't work. I think it may have been the mini blow torch!
Second try used a Bic lighter, slowly, worked well.
P.M me if you want me to get some packs to you.
Cheers

The NARVA brand appears to be down under. However, Amazon lists a very similar looking connector made by Tyco.