Refairing Keel Hull Join... Bit of a gap!

[RichP]

Hey guys,
I'm looking for some advice on re-fairing the front of my Keel to Hull join, as you can see there isn't much sealant left there!

The keel is Cast Iron and is attached to the boat with 6 3/4'' Whitworth Studs wound in with a nut and washer inside the boat.
I replaced the keel studs early this year and the boat has not been in the water since so I know they are good!

I'm know to do it properly the keel needs to be rebedded, but can anyone recommend a way to sort it out for a season and I will do it next year.

Cheers
Rich



Oh and here's what a 30 year old keel bolt looks like:

Change them!

[deniseO30]

Well it looks like it's beyond filling with 5200. it the sole to keel connection warped? Or is it just the keel hanging in the front? My guess is you need to do a structural repair and fairing of the keel bed. Your blog isn't there when I click on it.

[RichP]

Sorry, the blog moved, i'll update the link now.

The Hull part of the keel hull join seems fine so i deduct either:
- The front of the keel has corroded a lot and left said gap
- The front keel bolt stretched enough to let the front drop and create a gap
- That gap was there from factory and had a lot off bedding compound in it.


Not sure, I think if the keel had dropped at the front i would be expecting gaps all along the join, not just the front, in a wedge shape.
Of course the Hull could have distorted or any number of things. :P

[Stillraining]

If it were me and I planed on droping it all next year and have already changed the bolts then I would not worry about it.... clean it out as best you could...inject in some 4200 as far in as you can...then just mix up some Fiberglass structrual filler and fair it.... I would not even use epoxie as it will be harder to remove next year ...a little bottom paint and go sailing.

[RichP]

Ok will probs do that...
Have to go for the Sikaflex equivalent as 3M stuff is hard to come by privately in the UK.

[Stillraining]

FWIW ...I did not know there were keel configurations that allowed for bolt changes like that...I think most are cast in place like foundation bolts and a particle destruction of the keel is involved to change them..I'm now interested in knowing how mine is constructed.

Might be a good thread to start.

[merc2dogs]

Cast iron is normally threaded. lead is normally embedded. It's because of the need for deeper threading to produce the same strength in lead vs iron.
Iron has enough strength that it can hold with 'normal' bolts, lead would require a very deep thread and wide bearing surface to produce the same.
Similar to the difference between regular wood screws and screws made for use in MDF
Much cheaper/easier to place a 'J' bolt on the mold when casting lead.

Ken.

[GaryHLucas]

Everyone mentions bedding the keel, but I'd be more concerned about sealing the joint to prevent seawater from getting to the bolts and the threads, like it obviously did in the past. It doen't look like this keel dropped any. It looks more like a rough casting, or a casting corroded away somewhat. I just had my keel blasted down to white metal and it was amazingly rough and had a ton of filler to make it fair. I'm now in the process of putting all that filler back.

Gary H. Lucas

[RichP]

Well bedding the keel does seal the joint, that's what its for.
Just for this year I shall try and fair it as best as I can. The studs only cheap I can change the bolts again if needed.

Stillraining, cast iron keels are very common in the UK and the keels studs are usually just wound straight in. They don't come out easy though... Put up a hell of a fight!
It seems a very suspect practice to cast in a bolt that can never be removed...

[roline]

The cast iron keels on the Rush and Cal 9.2 have pockets on each side of the keel that the studs extend into and the studs have washers and nuts on both ends. Only the leading and trailing studs are into threaded cast iron.
As of to the gap that you have, I'm an epoxy fan even if you consider it temporary.

keelbolts