Keel Sump

[admin]

I've own "Dark Star" for over 10 years and there's never been any indication of exactly where the joint is located. This despite having run aground a couple times.

David, you are a lucky man! To me, this sounds like someone reinforced that joint with some hefty biax sometime prior to your having bought it, 10 years ago. We'd see a "Catalina Smile" in the forward 12-18" of our keel joint after a few "soft" groundings in the Chesapeake....up there you guys actually have things that resemble rocks!

[darkstar32170]

Yes, I am very lucky.

The sump was reinforced by the previous owner and seems to be rock solid now. Its built out a good 3/8" (thickness) and down about 6" inside the sump. The glass extends to and partway up the face of the bunks.

I spent one year in a harbor that had a very shallow entrance. Twice we ran aground and had to be towed off. Once was well inside the outer channel marker in gravel. The other time in sand in an area where at low tide we probably had a channel about 10 feet wide with very steeply sloping sides. I could take the spin pole at beam max and find water depth over half the length of the pole (missed it by 4 feet). I don't really want to go back to that harbor but can get a slip there for less than moorings everywhere else (guess why). Reportedly they have dredged out the narrow channel and there are no more problems there but I always felt it was touch and go (literally) in the outer channel. The scary time was not so much a grounding as a collision with the bottom. We hit solid rock twice in the trough of the waves. The first one nearly stopped us cold and everyone went flying. I went ass-high over the deck level traveller. Frankly I was surprised that we didn't drive the keel up through the hull. The only damage was to the tip of the keel - some gouges through to the lead. Its never been completely repaired because I can't seem to get the yard to keep the blocking far enough back to give me good access (maybe one of these years they'll remember my request).

The black fibers I have are not from any bacterial action. They are spaced at regular intervals in the weave. I do know that the original owner actually participated in the build so I suspect that some extra care was taken. I found this out at a regatta party one evening when Nan Hall came up to me and said, "I built your boat." She had seen us on the race course earlier in the day when she passed us on a J90 with a solid wing mast, something I think her husband Ben had been experimenting with.

Like I said I'll get some recent photos up on my website.

[musicman]

There are some uni black fibers exposed. I thought they might be black due to anaerobic bacteria from being wet. They may be carbon. It looks like I have to talk to John. I have his number, he didn't go down to Key West like all the A crowd did he?

I will be in Key West sailing not on Remedy though, the days of me dragging a 32 around are over....
Feel free to call me at the loft if you like 860 536 4235.
There are a number of issues with these sumps that need to be looked at, very carefully. There is a TON of speed to gain by eliminating flex.
Inboard boats are usually the worst.

[Motorboat!!]

Where exactly is this additional bracing placed in the sump? I currently have 2 braces that extend down into the sump, that were under the original i/b motor. One brace is approx 7" from the rear of the sump, and the other is just about in the middle of the sump. Are you saying that you installed additional supports? Or was my boat already modified? Dave Bolyard, a local sailmaker, told me that I should consider adding another support...Is this correct?

[Pterobyte]

Hi Matt,

I uploaded some images for John to look at on my boat.
Keel Issues:
http://pterobyte.net/renovation-log/keel-issues

Keel Box:
http://pterobyte.net/renovation-log/evelyn-32-2-keel-box




Bottom of main rib

[FlatlineE32]

Without seeing a picture it is hard to say if it has been modified. With the i/b they typically cut right through the aft brace to accommodate the shaft. This significantly weakens the sump. John added a steel brace to that particular spot. I will find the pictures of the reinforcement I did to mine. I used 3/4 marine plywood and glassed them in.

[musicman]

Hi Matt,

I uploaded some images for John to look at on my boat.
http://pterobyte.net/renovation-log/keel-issues

John had 5, most came with 3, I have 4 ribs. I have two, on each side of the mast base, one small stiffener and one real large one between the first 2 and the last 3 keel bolts.

Nice to talk to you today. Had a look at your photos, you have quite a bit of work to do this winter! Luckily you have a very nice place to work.
While you're boat does appear to have 2 extra floors if it were mine I'd add more structure. Do the 2 small floors extend into the sump?
i'd like to see one more large frame in between the little aft one & the middle.

What we did to ours (as Jason 'Flatline" mentioned) was added a number of floors all of which extend into the sump & across the floor of the boat.
The first one we made was to try & fix the mess made from the IB instalation. Many of the boats have the main keel frame cut in half to allow the shaft to pass. This is SERIOUSLY bad!!!
We made an alloy one quickly just before KW 05 to try & stop the flex. This part basiclly reconnected the cut frame & has a collar to allow work on the shaft. It helped but wasn't enough.
So after KW while getting ready for BIRW we dropped the keel down to address some sump issue & added 2 more frames. There was a BIG improvement in our upwind speed & pointing at BIRW from KW.
I'll dig up some photos for you guys to look at.

What you'll be very surprised in is that once you get the keel to stop wobbling around & get the bulkheads sorted out & beefed up the 32 is a MACHINE upwind in heavy air.

[Pterobyte]

From Musicman
(consolidated from keel fairing to keel sump)

Ok, so there was some discussion in the keel fairing thread about our sumps. As was mentioned there is quite a bit of speed to be gained by stiffening this area. In stock configuration they are under-reinforced, this is only made worse when the IB instalation cuts through the main frame. From what Bob has told me this method of IB instalation (with the motor over the keel & the frame cut in half) is the "factory" method of IB install on the 32.
We have done extensive work to this area on "Remedy" and found HUGE height & speed gains upwind.
Please post photos of your sumps in this thread for discussion.
Here is what it looked like BEFORE we re-built it:

[Pterobyte]

From Dark Star
(Moved from Keel Fairing)

I am going to get some pictures of my boat this afternoon and see what I really have there. I know that my aft support has a cut away to allow for the original IB shaft. How do you recommend strengthening it? What materials and how thick should the support be? Does it have to extend all the way to the bottom of the sump or just say half way? I am trying to figure out how beefy this thing has to be. Any help is greatly appreciated!
_________________
-Matt Skaer
MOTORBOAT!!
USA 32888

[musicman]

From Dark Star
(Moved from Keel Fairing)

I am going to get some pictures of my boat this afternoon and see what I really have there. I know that my aft support has a cut away to allow for the original IB shaft. How do you recommend strengthening it? What materials and how thick should the support be? Does it have to extend all the way to the bottom of the sump or just say half way? I am trying to figure out how beefy this thing has to be. Any help is greatly appreciated!
_________________
-Matt Skaer
MOTORBOAT!!
USA 32888

Yes take some photos. It would be gret to post them right into this thread, so if you don't have one already set up a photo hosting account like photobubket.com Load them there & paste the img tag into your posts.

I think it's very important for the new frames to go a long way doen into the sump. Leaving an inch or 2 gap at the bottom is fine & will help you to get the water out that accumulates in there. One thing to remember when fitting them is they should not be hard up against the inner wall of the sump. It's best for there to be a small gap & have the tabbing lock them in.
As for materials marine ply is just fine, no need for anything exotic.
Let's see what you've got first.

[Motorboat!!]

So here is what i've got...not too much there right now.

[musicman]

Well you don't have much there... The main frame is VERY low right at the turn off the sump to allow the coupler to pass, this won't be helping it's rigidity. And the other small frame behind it is much to low as well.
The main frame is tricky to correct as you need to allow the coupler room.
Our solution was pretty slick using a removable collar.

Have you ever jacked it up in the air to see how much the keel/sump wiggles when you push on it? I'd bet it moves quite a bit...
What hull number is this boat? If it's a C&C that main frame doesn't look original. My guess is this is a Formula boat.

In your case I'd start with adding a ply frame between the main frame & the front of the sump & add one attached to the front of the rear floor, making it taller by quite a bit.
You could get that done in a weekend & see how much it helps. If you need more stiffness look at correcting the main frame with a collar.

When I get back from KW I'll post some photos of ours.

[FlatlineE32]

Here are some pictures of my project.

Before. You can see the uni carbon in the lower left cut out.

[Pterobyte]

One nice job. you put us all to shame. Did you glass over the keel box or just drop in a plug?

I can borrow your Fein?

[FlatlineE32]

I did glass the keel box back in, but the structure comes from the laminated sheets of marine ply under it. I just wanted to make it look pretty by putting the box back in.

The Fein is a great tool. It is worth the investment.