Lightning strike

[HandHFarms]

I am looking for some advice on what to expect as my wife and I start repairing the mast on our Hunter 26.5 sailboat. It was struck by lightning in the marina and we took it out of the water and are just now starting to make the repairs in preparation for this summer. Does anyone have any good advice or links to resources that can help explain how to fix the masthead and sheave assembly. Yes I know the halyards need to be replaced so please don't judge. I'm doing research myself but I know alot of you have plenty of experience to provide. We are willing and able to do the work I just want to ensure I'm doing it correctly.

Thanks for any advice.

 

[Ralph Johnstone]

Yes I know the halyards need to be replaced so please don't judge.

Welcome to the site. No judgement at all. From your approach, you're obviously the type of person who does his research on a job and then goes at it and does it well.

Hang on for a few hours and I'm sure you'll be answered by others down your way who, as I remember, have had numerous problems with lightning strikes to their boats.

Fortunately, up here, that's one thing we have very few of, knock on wood.

 

[HandHFarms]

Ralph, thanks for the words of encouragement. Our family loves this boat and we were heart broken when the lightning strike happened. Luckily it happened at the end of the sailing season, but it made a long motor to our closest lift to have it removed from the water. It hasn't made it's way back in yet and has sat for the past 2 years. I feel like we are starting back over from scratch the way the boat was when we first bought it. It truly is a labor of love though as it has brought so much joy to our family being able to spend the nights out anchored in a cove.

 

[Justin_NSA]

I'm surprised that the mast was the only damage. The last strike here was on a multihull and it blew a hole in one of the amas!

 

[Ralph Johnstone]

How do the electronics look ? I understand those can be vulnerable.

 

[jssailem]

Welcome to SBO. Mother Nature can really doo a number on our boats.

What exactly did the lightening strike do to the mast head and sheave assembly?

I doo nt see any gross melting of the aluminum. It looks like someone took a crowbar to get the mast head off. If so then smoothing out the rough areas and seeking if the masthead will again fit would be in order.

• With the mast head off what happened to the electrical wires. Are they the black balled up bundle inside the mast? I would be inclined to remove the wires. Being sure to tie a messenger line to the wire so that you can pull new wire into the mast without having toe fish the wire done the mast.
• The aanchor light looks like the lens has faded due to UV. I would replace the anchor light.
• The antenna wire for your VHF also may be in that black glob. Pulling a new coax cable is in order. If the antenna fittings are still ok, then you should be able to attache the coax to the antenna.
• With the mast head down, now would be the time to replace the sheaves.
• You said you are going to replace the halyards. Were the sails a bit difficult to raise and lower at times? The halyard line diameter is too big for the sheaves you have in the masthead. Reducing the halyard line size and new sheaves should make raising or lowering the sails a lot more pleasant.

You have a nice boat and the refit will make you smile every time you untie the lines.

 

[BigEasy]

Unfortunately, a lightening strike has the potential to extensively damage a boat. Electronics including VHF, stereo, all instruments can be affected to the extent that they need replacement. The entire electrical system can also be impacted including but not limited to engine wiring harness, charging systems, batteries, and power distribution systems. You really need to have an ABYC qualified marine electrician evaluate all electronic & electrical components and prepare a report for insurance purposes. Thru Hull fittings & bottom are sometimes damaged, so those need inspection also. As far as the mast itself, now would be an opportune time to replace the sheaves if suspect, new anchor & steaming / deck light, new vhf antenna & wiring, new wiring for nav lights. Install a new wind indicator. Now would be a good time for mast maintenance; check spreaders for fatigue & stress fractures and clean mast thoroughly and apply aluminum polish. Your insurance company should have been notified when you realized the strike occurred so that they could arrange for haulout and a thorough bottom inspection as well as Electrical / electronics inspection. If you have a comprehensive policy, it should cover all damages, less any deductibles. These lightening strike claims can amount to thousands of dollars with the cost of electronics, labor rates of $75-100 / hour, and yard / dock storage fees for a few months. Good luck with the repairs. I have fortunately not experienced a strike yet; however, it is not uncommon here on the Gulf Coast, especially during summer thunder storms.

 

[kloudie1]

I had a strike several years ago.. It took the VHF antenna, fried the Loran (sorta tells how long ago it was) and the VHF radio. It exploded the bulb in the stern nav light, exploded all the little "peanut" bulbs in the breaker panel, and blew up the breaker for the nav lights. We did a thorough inspection of the standing rigging and found no damage. It is really strange how the damage was random; the other nav lights on the same circuit were not harmed, nor was the anchor light at the masthead. I was plugged into shore power and there was some soot around the ground wire outlets/inlets.
I know of a couple of boats that had no bonding grounds when they got hit. The lightning exited through the hull in a couple of spots and evaporated the resin from the glass in those spots, leaving weeping fiberglass gauze spots (2 inches by 2 inches) that were easily patched ..
Inspect the hull very carefully and on the standing rigging, pay particular attention to the up facing swedges. As John and Easy say, the masthead can be replaced after a bit of straightening/cleanup.
Good luck!

 

[JamesG161]

This is my advice on Lightning , see my post #5 here

newbie lightning protection?

Avoidance is best...
Jim...

PS: I have been well trained in Avoidance.

 

[HandHFarms]

So my question here is this. For the mast head it appears that it was just rivetted on. Is this correct? If so do I need to go back with stainless rivetts or will normal pop rivetts do the job?
Is there also a "best" sheave that I should consider as I put this thing back together?

Thanks for the advice.

 

[BigEasy]

do I need to go back with stainless rivetts or will normal pop rivetts do the job?
Is there also a "best" sheave that I should consider as I put this thing back together?

Check out the remnants of the existing rivets and use same material & size.
Call the folks at SBO store and order a replacement sheave. They should have the resources to determine the "best" size & type sheave
for your application.