sailorman
Well-Known Member
dive down and get it then...
its better used under water
Encapsulated keels
- Thread starter VicS
- Start date
its better used under water
Grajan
Well-Known Member
When using steel stampings and resin we found that by slowly pouring a standard slow cure resin mix into the keel first immediately followed by the stampings the resin didn't overcook the resin encapsulated the steel stampings and adhered to the keel moulding.
Our max mix of resin at any one time was 5lbs.
if no curing agent is added it will not cure! the solvent in the resin will eventually evaporate leaving a resin the consistency of tar and a very high chance of rust expansion from condensation.
Our max mix of resin at any one time was 5lbs.
if no curing agent is added it will not cure! the solvent in the resin will eventually evaporate leaving a resin the consistency of tar and a very high chance of rust expansion from condensation.
CAPTAIN FANTASTIC
Well-Known Member
I hope the encapsulated keels on my Macwester don't get like this one. What boat is it?
Appledore
Well-Known Member
+1 Thinking of my Rowan!
Avocet
Well-Known Member
Incidentally, although I can accept that lead would be very expensive, I seem to remember that our previous boat had punchings in the bottom, set in resin, but they were stainless. Surely that wouldn't be all that much dearer than mild steel?
Also (and I don't know the design of the boat at all) might there be a danger to the keel-to-hull joint area if the same weight of lead was used (because the bending moment on the keel would be greater as the centre of gravity of the mass would be further from the attachment point to the hull? (Though, on reflection, I don't suppose the design was so marginal in the first place as for this to be critical)?
Also (and I don't know the design of the boat at all) might there be a danger to the keel-to-hull joint area if the same weight of lead was used (because the bending moment on the keel would be greater as the centre of gravity of the mass would be further from the attachment point to the hull? (Though, on reflection, I don't suppose the design was so marginal in the first place as for this to be critical)?
Be kind to put people out their misery & tell them what boat that was.What a bloody nightmare!
KellysEye
Well-Known Member
>Not too difficult to fix. Remove all the old rubbish, repair the skin and fill with scrap lead and lead shot to fill any voids then add an epoxy resin to seal it into one lump. Hould last another 100 years
Given the corrosion you would need to cut the whole keel off and weld a new one on, then replace the ballast preferably with lead and ours had layers of tar. To a welder it would be not too difficult but it would be kin expensive and not worth it. My bet is there will also be corrosion in the hull.
Given the corrosion you would need to cut the whole keel off and weld a new one on, then replace the ballast preferably with lead and ours had layers of tar. To a welder it would be not too difficult but it would be kin expensive and not worth it. My bet is there will also be corrosion in the hull.
Tranona
Well-Known Member
It is a Sea Wych. VicS has explained how the ballast is installed. I built one in 1977. With a later owner the shoe wore off with similar result but not as bad. The keel moldings are integral with the hull, so the owner chipped out the old rubbish, remade the bottom of the keel and reballasted it.
rob2
Well-Known Member
The problem is that it is just not cost effective to repair. It can be done as a labout of love, but (without knocking the Seawych) it's just not worth it when you can go to the next yard and buy a serviceable one for less than the cost of repair. It does serve as a reminder to all those with encapsulated keels that the integrity of the underwater parts must be maintained. Although my keel is encapsulated lead not iron, I moved from a cheap, half-tide swinging mooring as the outer skin of a boat of similar construction had worn through the skin. The repair entailed cutting the skins off the keel to dry out all the water that had wicked up inside!
Rob.
Rob.
onesea
Well-Known Member
Is the hull strong enough to grind off the keels and replace with steel plate with bulbs at the bottom?
Otter
Well-Known Member
Just how common is this sort of thing? I've tramped around most boatyards and marinas on the East Coast and never saw anything with even mild symptoms described - never mind the catastrophe shown! Can't help thinking that if it was common we'd see ads in the yachting press for "encapsulated ballast treatment centre" 
Tranona
Well-Known Member
Not common at all. Most boats with that type of keel have very thick layup at the bottom. The Sea Wych is not particularly thick and relies on a sacrificial moulding attached to the bottom of the keel. Once this has been "sacrificed" and not replaced constant drying out on a rough seabed (as happened to my old boat) the GRP wears through, water gets in...... On other boats it can happen when the hull is moulded in two halves and the join cracks with similar results.
So, uncommon, not not unknown.
So, uncommon, not not unknown.
AntarcticPilot
Well-Known Member
Just how common is this sort of thing? I've tramped around most boatyards and marinas on the East Coast and never saw anything with even mild symptoms described - never mind the catastrophe shown! Can't help thinking that if it was common we'd see ads in the yachting press for "encapsulated ballast treatment centre"
I'm afraid the comments about it not being an economic repair cover the reason why you don't see commercial repairers as you do for osmosis!
