Mast Wiring

[Terra Nova]

The wire channel on TN's mast (a Kenyon) is like the small compartment on the right of your photo. Being stepped on top of the keel, wiring exits just below deck.

[Steve Olson]

Originally Posted by a64pilot

If you drill into the mast, be sure to de-burr the hole to prevent any stress risers

Ok, what does it mean to "de-burr"?

[Badsanta]

When you drill a hole it leaves very sharp edges or burrs on the inside and outside edges of the drilled hole. To de-bur means to sand or cut smooth the edges so it wont cut the wire as it rubs the burr. Even after smoothing the sharp edges wrap the wire with friction tape to protect it from being cut.

[a64pilot]

BadSanta got it right, but for the wrong reasons, any hole is a potential weak spot, the "burrs" or sharp edges are "stress risers" Stress concentration - Wikipedia, the free encyclopedia
It's just too easy to ensure a smooth hole and it will increase fatigue life of the part, in this case the mast of course. I come from aircraft manufacturing / maintenance, and there you always de-burr any hole you drill. I think a mast is pretty similar to a wing spar although I have no idea how many masts actually fail, but bet most failures are due to fatigue.

[Steve Olson]

Thank you both for the info! What would be best to use to smooth down this metal surface? And I'm thinking a Luna Sea clam would be a good solution to prevent water from entering this hole?

[a64pilot]

I'm assuming a large hole like 1"? If so I'd just use something like 800 wet or dry sandpaper and my finger, all your after is smoothing out the hole.
Now I know nothing about masts, like I have no idea where you should or should not drill a hole in a mast.

[Steve Olson]

Originally Posted by a64pilot

I'm assuming a large hole like 1"? If so I'd just use something like 800 wet or dry sandpaper and my finger, all your after is smoothing out the hole.
Now I know nothing about masts, like I have no idea where you should or should not drill a hole in a mast.

I want to make the hole only as large as I have to in order to fit the cable end plug through. I'm assuming that the structure of the boat wouldn't be too jepordized by drilling a hole. Obviously other sailboats have done the same. I'd like to hear from someone who can tell me if I need to do anything to reinforce the area surrounding the hole or if it would be just fine without reinforcement.

[Terra Nova]

64--Pretty sure you mean 80 grit, not 800, which is so fine it would take hours just to deburr 1 hole.

OP--There is no need to reinforce around the hole.

[a64pilot]

Actually I believe 400 would be the ticket, just couldn't remember. 80 is pretty rough isn't it? We aren't trying to remove anything much, just smooth the hole.
I wouldn't think you would need a doubler either, but I assume thats a question for a rigger?

[Steve Olson]

Originally Posted by Terra Nova

64--Pretty sure you mean 80 grit, not 800, which is so fine it would take hours just to deburr 1 hole.

OP--There is no need to reinforce around the hole.

Perfect - thanks!! I'll be picking up the Raymarine radar cable this week. I will measure the plug when i get so as to not make the hole any bigger than I have to. This little project started from my desire to replace the standing rigging on my boat (which is original). It's evolved into mast/steaming light replacement w/ all new rewiring for that, a new wind transducer w/ new cabling, adding radar (just above the steaming light), and a complete compression post rebuild using 2"x2" SS tubing. I'm looking forward to getting it all back together so I can actually do some sailing this Spring/Summer. I'm new to boat ownership, so this is good experience for me.

[a64pilot]

My Garmin had a removable plug that made it so the hole didn't have to be that big, I know nothing about Raymarine, but take a look at the plug maybe it's removable too? It was just the plastic outside that removed on the Garmin, no replacing pins or anything.

[Steve Olson]

Originally Posted by a64pilot

My Garmin had a removable plug that made it so the hole didn't have to be that big, I know nothing about Raymarine, but take a look at the plug maybe it's removable too? It was just the plastic outside that removed on the Garmin, no replacing pins or anything.

Thanks for the heads up! I'll take a look for that.

[Badsanta]

Just a suggestion. Your tri color top of the mast light is for sailing only. Your steaming mast head light the one below your radar is for when under motoring power and your bow lights are for motoring or under sail. When under sail dont use your steaming light. I was confused with this at first.
Also the lights are listed as a minimum size for boat lengh. You can go larger but not smaller. I went with aqua signal 40 for my boat. They were twice the size of the original ones and the LED bulbs are great. If you go with the LED bulb inside the red green lenses don't use a white LED you will end up with a pink and blue light. Something about light waves through plastic. But use red under red lenses and green under green will work great. I know sombody will start in on visibility and distance and they can explain it. My lights are the brightest at my dock and that is what I want. Sorry I never had stress problems at drill holes but have had cut wires. If you already know this great. I was only trying to help. Don't ask why I have $150 in white LED bulbs that for that pink and blue look.

[Steve Olson]

This is what I have to replace my masthead light. It's from Lunasea and offers green/red for navigation, white for anchor, and also has a strobe feature. I'll be running 3-stran 16 gauge wire to it. It uses a common ground and two independent positives (one on for nav, the other on for anchor, and both on for strobe). http://www.lunasealighting.com/docs/LLx-53BK-81-00.pdf

[Badsanta]

Looks great.