Sunday, June 23, 2013

Deck Hardware Rebedding

This is one of those "out of sight, out of mind" maintenance tasks that all too often gets ignored until it's too late. But, eventually, all the deck hardware on a boat will need to be removed an rebedded; it's just one of the joys of owning a boat. Four to six years is about all you can expect from the bedding compound on most deck fittings, before leakage starts to manifest. So, I try to follow the 20% rule for an older boat: Re-bed 1/5 of the deck hardware every year in a constant rotation, and you'll never fall too far behind.

If water does begin to leak past the deck fittings, into the coring, the coring will become water soaked and begin to rot. In time, expensive and time consuming repairs are sure to follow. It's important to stay out in front of this one....

So, for this post, I will demonstrate how I removed and rebedded all the bow hardware - the bow cleats, anchor roller, scuff plate, windlass, etc.

The first step is to simply unbolt and unscrew all the items, and strip the deck. Once everything is out of the way, thoroughly clean the deck, and all the hardware, of all the old bedding compound / sealant. Then, you have to assess the deck, and see if any water has intruded on the core. If it is dry, you are in good shape. If it is wet, you'll have to assess the damage. Coring that is just recently wet, but not rotted or weakened, can sometimes be dried out, if the water didn't get too far. Time, strategically placed heat lamps, a vacuum cleaner, and sunlight are all your friends when it comes to drying a core. It's  time consuming, and could take weeks or longer to get completely dry. If it is really wet or rot has begun, the only proper solution is to expose it and do a core replacement. There are plenty of articles online and in written publications covering core replacement, so I am not going to get into it here, but I will state that I am not a fan of epoxy injections or other "band-aid solutions". Fix it right.

So, you now have a clean and dry deck, but it's still not time to put it back together. Very often on production boats, the factory will drill screw holes, place the item over the holes, and screw it down with bedding compound underneath. But, now that you have it apart, you can do better.

First, I enlarged each screw hole to 1/2" diameter, with an electric drill. I drilled through the upper fiberglass skin and core, but not the lower skin. Then, I mixed up a batch of West System 105 epoxy with a thickening agent (Cab-O-Sil), and pumped it into each hole with a syringe. For larger through holes, I enlarged the through hole a couple sizes, blocked the bottom of the hole with tape, and filled them as well. When I was done, the bow looked like this:



The next step is to redrill each hole back to its original size. When this procedure has been executed, you'll be left with a waterproof epoxy liner for each hole, so if the bedding fails down the road, the coring is still protected from water intrusion. Also, be sure to countersink the top of each hole slightly. That way, when you apply the bedding compound, a ring of sealant will remain in the countersunk area, providing a greater degree of elongation capability, and a more robust seal.

For the larger through holes for the windlass and spotlight, I applied two coats of epoxy with a brush, and let it cure for 2 days before reinstalling the components.

Once all this preparation is complete, the actual install goes quite rapidly. The finished install looks like this:


All sealed up from the elements....and the coring is safe for years to come.