Waterproof electrical connections?

[TheBigGuy]

Well I've been working on my boat for weeks. Started as a simple bilge pump replacement and ended up being a major project. I've upgraded my fuel system, electrical system, battery housings etc, etc, etc. I had no intention of doing all the work I've done at this time of year, but one thing led to another, and another. I've just about finished now, but I thought I'd share my method for making a watertight electrical connection in case it might help other guys.

I have no idea if my method is unique, but I've never read about it anywhere else. Maybe others have a different way that is even better, but I've found this method pretty good for maintaining a solid long lasting watertight electrical connection.

First off, if your not into soldering this method probably isn't for you. Although the procedure can be used without soldering. For any submerged connection I generally solder. I may use a butt connector if it's large gauge wire, but I generally solder the two wires together. Sometimes if it is not submerged I will crimp on a terminal, but I will still usually solder the terminal after crimping.

The next part is what leads to a rock solid watertight connection. I use a glue gun with the plastic glue sticks to cover the wire connection with a large coating of glue over the solder joint. Next I use a heat gun to even out the coating of glue over the connection. The glue should cover the connection and at least 2 inches on either side of the joint. Next use a an appropriate size of heat shrink tubing to completely cover the joint and and the several inches of glue on either side. If the tubing won't quite slide over the glue, use the heat gun to even out the coating of glue until the heat shrink tube will slide over top. Make sure the glue has cooled before you try sliding the tubing over top, or it will start to shrink before you get it in place. Once the shrink tube is in place, hit it with the heat gun on a medium heat setting. Heat around the shrink tube evenly starting in the center. The glue underneath the shrink tube will heat up and will start squeezing out the ends of the tube as the tubing begins to shrink. Once the tubing has shrunk as much as it will shrink, wipe off most of the excess glue that has come out the ends. Spread some of the excess glue around both ends of the tubing. Use the heat gun to make a nice smooth coating of glue all the way around both ends of the tubing. The combination of the shrink tube and the glue totally prevents water from penetrating the connection if done properly. Once you have gotten the hang of this type of electrical seal you will find it lasts amazingly long compared to any other method.

I have been using this method on my trailer wiring for a long time now, and I hardly ever have to redo my trailer wiring using this method. Usually when I have to redo the wiring it because someone has damaged my lights at the ramp while I was fishing.

This method also makes beautiful terminal connections if it is not in a submerged location.

Maybe this method is common knowledge, I have no idea if anyone else uses it. As I said I've never read about this method before. If this is old hat for wiring gurus, I guess I didn't exactly come up with anything new. If it isn't widely known, then I figured it might really help guys get a good long lasting waterproof connection.

Here are some pics on how I seal my connections with a glue gun and heat shrink.

Cover the connection liberally with melted glue.

Shrink the tubing completely with a heat gun.

Afterwards I smooth the excess glue around the top ends of the heat shrink and the wires to completely seal it from water intrusion.

Hope it helps some guys. Feel free to post your method if you think yours improves on this.

 

[Birdsnest]

This is a good topic for it is not easy to make these kinds of connections last specifically with the positive connections. I have had many soldered connections with heat shrink fail over the years. I think that the hot glue is a good addition but I would add that it is important to use a high quality heat shrink.
I have stopped using soldering as a connection method and now only use heat shrink (clear blue or pink or yellow stuff) connectors where I dip the ends of the wire in electrical grease prior to crimping and shrinking. I have not had any failures since I changed to this but I have only been doing this for 7 years or so my connections have not officially stood the test of time.

I certainly do like the hot glue method above but I have good results with what I am doing now and its easy.

 

[TheBigGuy]

I have a very good set of pro grade crimpers and I do crimp some connections, but I still like to solder most crimped connections. I just think you can't beat a soldered joint for a good solid connection. I know soldered connections do fail, but I've had no problems using this method. I think one of the reasons soldered connections fail is because they can end up being brittle and cracking with all the vibration on a boat. Using the glue and heat shrink turns the soldered joint into one big semi rigid unit with very little flex at the solder point. It's kind of like having a big "cast" around the connection point for reinforcement. I think the glue almost totally eliminates the failures that can occur from the joint fatiguing and cracking over time because of flexion or vibration.

If your not a big fan of soldering you can still use glue and heat shrink to really improve the seal and strength of your preferred type of connection.

 

[ChilliSpoons]

I like these ideas. And I like the idea of using electrical grease in the butt end connectors.

What about the use of Liquid Electrical Tape?

 

[SpringVelocity]

This is a good topic for it is not easy to make these kinds of connections last specifically with the positive connections. I have had many soldered connections with heat shrink fail over the years. I think that the hot glue is a good addition but I would add that it is important to use a high quality heat shrink.
I have stopped using soldering as a connection method and now only use heat shrink (clear blue or pink or yellow stuff) connectors where I dip the ends of the wire in electrical grease prior to crimping and shrinking. I have not had any failures since I changed to this but I have only been doing this for 7 years or so my connections have not officially stood the test of time.

I certainly do like the hot glue method above but I have good results with what I am doing now and its easy.View attachment 28707

Those connectors shown are great. I have environmental tested those crimps in the harshest marine environments for marine solar enclosures. We even tried to accelerate failures with UV and immersion testing. The only thing about those connections is you have to watch not to burn the insulation, and use proper crimping tools. Other than that very robust, all I use in my boat, and when designing products for outdoor environments. We always preferred these crimps on the manufacturing lines with operators vs soldering. Soldering especially now with non leaded solder takes a little bit of training and right equipment to get it right ( this was a pain BTW training people when non leaded soldering came out). Many failures I have seen over the time is not the crimp it is someone overheating the insulation with heat gun.

If done correctly you dont need anything additionally.

 

[scott craven]

what crimp tool works the best ?

 

[bones]

Nice job
What kind of wire do you use? TWH75 stranded?
lol... More than likely it not waterproof. Those butt heat shrink crimps are expensive but quick and do a great, job fast and great positive connection. I never put the joint compound in a heated connection as I find it just pours out when heated. Maybe some stays in.

 

[SpringVelocity]

what crimp tool works the best ?[/Q

what crimp tool works the best ?

Scott I am not sure which one I have. I think mine is an Ampco I got from Queale Electronics. DigiKey has them as well. When you go on Digikey site you can match up depending what connector your using. The best connectors are the anchor ones, but you can buy the same ones from DigiKey cheaper. All anchor does is resells them. If you buy in bulk its cheaper. There are some ****** ones out there you want the ones with inner melt. And BS there totally waterproof I put these in salt water and heat cycled the crap out of them in special thermotron testing oven. They are tough when done right.

 

[Birdsnest]

I have always used this stuff from CT. It does not run when heated but when using it with heat shrink you do not want to get in on the inside of the heat shrink when you put in in the connector
.
Ya the anchor heat shrink products are the best and I have bought them in bulk from the US on eBay for they are incredibly expensive here in canada.
Id try and keep any connections out of the water at all cost.

 

[bones]

Scott we use the Greenlee ratcheting crimper with removable die. Works great puts a hex style crimp on the terminal. This way there are no hot spots on the crimp.

 

[scott craven]

Great, thanks for the info guys

 

[TheBigGuy]

When I do not solder I use ancor products as well. I have a ratcheting anchor crimper, use ancor connectors, and ancor tinned marine grade wiring.

When I want lots of extra protection I do the full Monty with lots of glue and extra heat shrink covering everything.

 

[fshnfnatic]

I used a brand of heat shrink tube called "Pico" in a recent rewiring job on my DE.It was a dual wall type which had
its own adhesive built into it that melts when heated and totally seals your connections.All my connectors were and marine grade wire
were Ancor brand and were crimped with a ratcheting crimper.I was told by a certified marine mechanic not to solder
any joints as vibration would eventually break the fine copper strands of marine grade wiring where they meet the
solid inflexable soldered strands.I guess time will tell if it will hold up to the extreme marine enviroment or not.

 

[aheny]

In my career I actually had to perform waterproof splices in Industrial settings. There is actually a UL approved process utilizing putty and various electrical tapes for a legal explosion-proof waterproof splice. It uses 3M electrical putty, Super 88 linerless splicing tape and 310 electrical tape.
This splice will last submerged in a significantly acidic environment

 

[sly_karma]

what crimp tool works the best ?

Channel Lock make an excellent crimp tool, model 909. Mt truck electric guy says they're almost the perfect tool for all his work except the cutter isn't as sharp as some other brands.

 

[TheBigGuy]

Channel Lock make an excellent crimp tool, model 909. Mt truck electric guy says they're almost the perfect tool for all his work except the cutter isn't as sharp as some other brands.

I use those type sometimes for the larger sizes my ratcheting crimper doesn't fit. Ratcheting crimpers are supposed to do the best job. For the monster size cable like the wires going to start outboards I have to borrow a set of huge crimpers from my neighbor who owns a fleet of boats. The crimpers for those wires are the size of boltcutters.

Luckily I still have lots of lead solder stockpiled, as I still prefer to solder crimped connections as well. I have used the silver solder, and I can make a good connection with it, but I still prefer to use the lead solder. The experts may disagree but I still think a good crimped on connection with solder and lots of glue and heat shrink is a super solid connection. I have no worries about my connections failing.

 

[TheBigGuy]

Chilispoons asked about liquid electrical tape. I've used that in the past, but it not my favorite way of covering a terminal connection as it makes a big mess of everything. It is also not very durable in a location exposed to the elements. I tend to use Lanocote the most for covering all terminal connections. Lanocote is a like a type of marine grease for corrosion protection. There are other spray on coatings I've used as well, but like the liquid tape I didn't like the mess it makes of everthing. I've found Lanocote does a good job of preventing corrosion on connections without making a big mess of everything. Much nicer for when you need to change the connection the next time. You wouldn't belive where Lanocote comes from. Take a whiff of it and you might be able to guess if you've ever lived on a farm. Haha.

For tagging/labeling connections I cut up an old sheet of plastic that was a sled my kids used when they where young. I cut it into Strips then size each tag, then drill a hole on one end. Zap strap the tags to wire. Write info on plastic tag in felt pen. Voila a great use for a plastic sled that was basically just a sheet of plastic with handles I was going to toss in the garbage. . Wish I had another one of those sleds as I'm down to my last few Strips after may last batch of electrical labeling.

 

[wildthing]

another method that will start to become popular soon is the uv epoxy
just needs a special black-lite and it cures in seconds...

 

[TheBigGuy]

That sounds way too quick. I wouldn't have an excuse to have a bunch of drinks while I meticulously play with my glue guns and soldering torch. Technologies ruining everything.

 

[sly_karma]

My electrical supplier does most of his business with logging trucks, has done for decades. We both figure the vibration issues are about the same with boats and log trucks. Salt corrosion occurs with trucks too, but not a year round issue as with coastal boats. His mantra is crimp, solder, heat shrink. Worked for me so far.