SailNet Community - View Single Post - wet keel
Thread: wet keel
View Single Post
  #5  
Old 04-01-2013
Jeff_H's Avatar
Jeff_H Jeff_H is offline
Moderator
 
Join Date: Feb 2000
Location: Annapolis, Md
Posts: 6,533
Thanks: 5
Thanked 85 Times in 65 Posts
Rep Power: 10
Jeff_H has a spectacular aura about Jeff_H has a spectacular aura about Jeff_H has a spectacular aura about
Re: wet keel

The answer heavily depends on the boat and its construction. A lot of boats, if not the majority of boats with encapsulated keels have large voids between the encapsulation envelope and the ballast. If the ballast is lead, and the void pretty small, its no big deal.

But with iron, or worse yet,with a mix of iron and concrete, it is very important to get it as dry and sealed as possible, since rust will pry the keel apart over time. In that situation it is hard to say whether this has resulted in a structural weakening of your boat. The connection between the ballast and the envelope is often a critical part of the structure, and when the ballast is iron and matrix, once that bond is destroyed, it really cannot be properly repaired without incurring a major expense.

The other issue is that a boat with an encapsulated keel, can drive the ballast up into the bilge membrane in a hard grounding which allows water to get into the ballast from above, or a small hole in the encapsulation membrane to cause the boat to leak.

The other issue is that there can often be moisture trapped in the glass itself. In that case there is no easy way to dry out the encapsulation envelope and any water saturated glass should be cut away and replaced.

I have heard of people using heat lamps and building tents with de-humidifiers in them, rigging up 'vaccum bags' and sucking as much air through the cavity as possible and so on. But none of these are especially quick if the plan is to do a permanant fix. My sense is that you should be able to drain the encapsultation as best you can. Then repair the majority of the holes by leaving a small hole at the top an several small holes at the bottom so it can continue to drain. Then make seal the holes with 'underwater setting epoxy' and glass over the plugs until you can make a permanent repair.

But the difficulty of making a proper repair are in part the reason, that I would never buy a boat with an encapsulated keel.

Jeff
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Curmudgeon at Large- and rhinestone in the rough, sailing my Farr 11.6 on the Chesapeake Bay and part-time purveyor of marine supplies
Reply With Quote Share with Facebook