Some Tips on Installing Electronics
Hooking up electronics in boats require some special attention. You can find general information on this topic in several places, but here are some things to pay special attention to in skiffs:
- Don’t be shy about calling customer support. Furuno, ICOM, and Simrad (among a few others) have positive customer service track records. This is part of what you get with a more expensive device, so you might as well use it!
- “High and Dry” is key – Try hard to keep installations out of the bilge, and away from batteries, fuel lines and direct sun light
- Stay clear of bilge pumps, battery chargers, windshield wiper motors or anything else with an electric motor or permanent magnets in it. Magnetic fields, in addition to messing with your compass, and can cause electrical interference
- Minimize or avoid looping or “spooling” wires – Especially antennae transmission lines (coax) or data wires (like the NEMA wires from device to device) because current running through unshielded wire loops can cause interference
- The ABYC specifically recommends against soldering marine electrical connections. Good marine-grade crimps and adhesive shrink tubing are the preferred way to connect wires in boats
- Beware the Sun – Most people focus on moisture protection when rigging a skiff, but you should also keep a eye on the sun.
Devices that are “waterproof” are usually sealed and pressurized with a dry gas to prevent fogging. If they’re left in the sun and get hot, the internal pressure can build up enough to pop the case apart.
We’ve had this happen to both a sonar unit and a GPS. This is NOT covered under most warranty! Try to locate electronics where they can get some shade in really hot weather, or be prepared to cover them with a wet towel.
These are nifty little gadgets for sealing off cable runs through exterior bulkheads. You have to drill a hole through the rubber stopper, then split it so the washer fits over the cables. Run the cable through the Cable Clam, then slip the washer over the cable so that it will be forced into the top piece when the top piece is screwed down. When the top piece is screwed down, it will compress the stopper so it flares and seals around the cable.
Cable clams have made it easy to add or remove devices that require cable runs through bulkheads, such as transducers, antennas, power cables, etc. but they are not cure-alls. They work best when sealing single cables, but not so well for multiple larger-diameter cables.
Most people working around boats have heard of 3M 5200 and 4200. They are polyurethane adhesives that are incredibly tough, waterproof, and stick like grim death. Unfortunately, like grim death, they can be almost impossible to remove if you make a mistake. Anti-Bond 2015 is a solvent that actually removes 3M 5200 and 4200 adhesives.
Anti-Bond 2015 really works. It softens 4200/5200 and most other caulks, and loosens/destroys the bond enough so that the pieces can be separated. Once separated, application of more AB2015 allows you to scrape the remaining adhesive off with a fingernail or a hard plastic scraper.
Here’s an easy way to make clean repairs of holes in white gel-coated fiberglass: Clean the hole, then fill with white Marine-Tex epoxy. Leave a slight bulge. Then take a strip of mylar packing tape, and place over the hole. Flatten the glue bulge so that it is flush with the surface. Let cure, then remove.
You will get a smooth glossy surface over the hole. This technique can also be used to patch fairly large holes, if you can put some mylar tape behind the hole as backing. Fill the hole with Marine-Tex, and place another piece of mylar tape on top, and press smooth. The shade of white will probably not be an exact match, but will be close enough.