Keel cracks

[BristolDiver]

Btw would this happen to be a Sigma33?

Sigma, yes, but a slightly bigger one that hasn't been around a race track.

Gone back over the original full-res pics, but can't see the crack you describe.

The shot with the gas sensor (compass!!) in is taken looking aft. Mast compression post is about 2ft off bottom of shot hidden under floor. I have another shot further aft of under the galley floor of the aft end of the keel but its in poor focus. The beams are showing some signs of possible repair with tell tale white fibre glass goo around an access hole that has been drilled through the floor hatch rim to access a keel bolt, that is itself covered in black goo. Oh dear

This was a fantastic looking boat, and although I'd seen this at the time, its only now that the doubt has crystallised with the help of the forum, and looking back over the evidence that was there to see. The 120 photos I took weren't wasted then

I'm pretty sure I've now managed to put myself off this one and walk, but curiosity will probably push me to at least ask about the circumstances here.

I assume if there is evidence of proper damage/post-repair survey reports and receipts from reputable repairs this is much less of a worry?

 

[Deleted member 36384]

Forward Momentum Grounding Is Likely To Compress Hull

...... Contrary to what some other posters say, I would have thought that if the lower forefoot of the keel was hit while in forward motion it would pull down the front top area of keel ( tensile load) and push up the aft upper area (compression).....C_W

Bristol Diver glad you have some opinion which helps you to move on.

Clyde Wanderer your observation on possible loads would not be considered correct in a static analysis (assuming the boat hit a stationary object). The keel hits the obstruction and stops (it doesn't matter if it continues to move as its the rate of de-acceleration that loads the front edge with a force). This is the key point. The keel is now fixed in space for a load transfer analysis. The momentum of the boat is transferred into a shear and compression load on the front of the keel and maybe across the whole keel.

Why compression and not just shear load across the keel bolts? Initially the boat will try and continue to move forward. This produces pure shear in line with the direction of motion (keel bolts shear load failure possibility). However two additional things now happen. The boat effectively takes a nose dive over the stationary keel because there is limited resistance by the water and gravity bears down as the hull is likely to be lifted out the water some what. Both these dynamic conditions produce downward force on the keel i.e. compression as the boat is forced into the fixed keel.

A forward collision low down on the keel nearly always produces a compression load on the hull / keel interface which is why the stringers crack.

For your position to happen the boat has to be fixed in space and the obstruction strikes the keel. This case can occur if the keel can move after the load is applied i.e. striking a cill at speed with the bow up and stern squat. The boat bumps over the cill before the forward momentum is transferred into a compressive load and the shear loading is not at right angles to the keel bolts or hitting a lee shore on a swell / surf where the back of the keel strikes first.

To be fair, what I describe is idealised and the attitude, speed and rate of de-acceleration of the boat to the various axis will determine how the loads are applied. So its not straight forward. None of this helps the OP and is pure navel gazing analysis.

 

[wotayottie]

I assume if there is evidence of proper damage/post-repair survey reports and receipts from reputable repairs this is much less of a worry?

If there has been repair, then the evidence of the crack shows that it wasnt done properly. That crack (if it is a crack) should either have been welded which is very difficult or the keel replaced.

Walk away. If you buy it you will not have peace of mind afterwards.

 

[boatmike]

Looking at the bottom of the keel It is pretty clear that this boat has been dropped from a great height. If it had hit a rock when sailing the damage would be to the front of the keel not the bottom and the turning moment would never cause damage at the top front but be forced away from the hull at the front. If it had been dropped on the front of the keel the force of impact would have been taken by the top front and possibly broken in just this way. Unless you are able to get a substantial reduction in price allowing for the cost of a new keel and full survey and proper repair of any hull damage I would suggest you pass on this one. It's obviously been "bodged".

 

[Tranona]

It seems clear ther is a problem with this boat. However, if the rest of the boat is "right" then not necessarily a reason to walk away. If you can identify this problem so will other buyers and the seller will know that he will have difficulty in selling. Try to find out the history and perhaps even have a surveyor look just at this issue as I am sure it is repairable. However you may not want to be the one involved in the repair, but that depends on what the end result is for you.

BTW I wish I had taken a photo of the bilge area and keel bolts of my Bavaria to compare with a "proper" boat as in your photos!

 

[Goldie]

BTW I wish I had taken a photo of the bilge area and keel bolts of my Bavaria to compare with a "proper" boat as in your photos!

If you're quick, it might not be too late......

(in jest, honest ... )

 

[photodog]

hmmmm.... 20yr old Sigma 33 with big chunks missing from the keel and a almighty dodgy crack.

Run.... dont walk .

 

[David_Jersey]

Leaving aside any technical issues, this thread has shown that your resale market will be more limited - just from seeing what you can.

I would also be asking why the owner never fixed it - the answer to that is of course it ain't worthwhile for him £££ wise. Unless you get a full proffessional repair (plus the aggro factor, and some contingency £££'s) factored into the price I would go and buy one without this "quirk".

 

[Tranona]

If you're quick, it might not be too late......

(in jest, honest ... )

Even in jest, I think you missed the point. These photos clearly illustrate why I don't think I would ever touch a boat of this era - built before there was full understanding of the properties of the materials in use, never mind the poor construction and finish in the bits you can't see.

After we polished the bilge area of our Bavaria you could eat your dinner off it and see your face in the shine on the keel bolts and backing plates.

 

[boatmike]

Even in jest, I think you missed the point. These photos clearly illustrate why I don't think I would ever touch a boat of this era - built before there was full understanding of the properties of the materials in use, never mind the poor construction and finish in the bits you can't see.

After we polished the bilge area of our Bavaria you could eat your dinner off it and see your face in the shine on the keel bolts and backing plates.

So you believe we didn't understand how to build boats 20 years ago and Bavaria are an example of how much better they are now!!!
Dream on......

 

[Ubergeekian]

After we polished the bilge area of our Bavaria you could eat your dinner off it and see your face in the shine on the keel bolts and backing plates.

Wouldn;t it have been better if they'd built them strong rather than shiny?

Let's get this into perspective, guys. A very small bit appears to have broken off the flange of a keel. Although that may indicate further damage, and certainly warrants investigation, there are definitely less-worrying ways in which it might have happened. For example, as I wrote before, improper tightening sequence of keel bolts. Or the keel fell over while removed for cleaning. Or the boat was lifted off the keel by someone who missed the front two keel bolts.

OK, not signs of masterminds at work, but it is quite possible that the hull is fine. The thing has been sailing like that for years, hasn't it?

If the price was right (at a guess, 20% below what others go for) and if I wanted one I would certainly think it worthwhile to investigate this further.

 

[David_Jersey]

After we polished the bilge area of our Bavaria you could eat your dinner off it and see your face in the shine on the keel bolts and backing plates.

And the smiling faces of the crew.

Inside

 

[Tranona]

Wouldn;t it have been better if they'd built them strong rather than shiny?

QUOTE]

Where have you any evidence they are not strong? Strength comes from design and materials appropriate to the loads. Mine is 9 years old and nothing has broken or fallen off.

Would you have confidence in the build of a boat that was as scruffy and as poorly finished as the one in the photos?

BTW I seem to remember you contributing to a recent thread on the need to rebuild the inside of certain Westerlys including your own to stop the keels falling off. Are these what you call strong, well built boats?

 

[rudolph_hart]

Sigma keel bolt location

If you look at this post by Thembi http://www.ybw.com/forums/showthread.php?t=218754 and the photos he posts, you can clearly see that the very forward part of the Sigma 362 keel flange has two athwart studs. Even though this is a wing keel, I'll bet that the fin keeled version and the earlier Sigma 36, have the same format.

Given this information, I would consider it vital to have a real close look at the stringers inside, 'cos someone's definitely done some some messing around with them - why?

I would also insist that the external areas around the keel was taken back to gel coat, so I could get a real close look at it.

 

[nct1]

http://www.cruisersforum.com/forums/f55/nasty-looking-crack-in-grp-fibre-near-keel-bolts-25277.html



http://www.p-m-c.nl/documenten/AccidentinCroatia.pdf

 

[Woodlouse]

Even in jest, I think you missed the point. These photos clearly illustrate why I don't think I would ever touch a boat of this era - built before there was full understanding of the properties of the materials in use, never mind the poor construction and finish in the bits you can't see.

After we polished the bilge area of our Bavaria you could eat your dinner off it and see your face in the shine on the keel bolts and backing plates.

It's great that Bavaria are using keel bolts and backing plates. Problem is they ain't bolted to anything significant. But hey, as long as it looks nice.

If you are serious about buying and you get a survey, ask the owner to fully remove the floorboards prior to the survey. The surveyor can only survey what they can see, they won't remove any screwed panels...if you think about surveying a wooden boat where would they stop??

A surveyor who doesn't take a screwdriver with him to take up the cabin sole to inspect the floors isn't worth employing. If there's something that requires looking at behind a screwed panel then a good surveyor will remove that panel.

It's usually easier with wooden boats as generally they're more open with their interiors so there's less to unscrew before you get at major structural components.

 

[Tranona]

Not quite sure why you are posting these links here - other than, I guess to knock Bavarias.

The failure on the Match 42 was well reported at the time. However, despite the death there does not seem to have been an official investigation and report so there is no definitive conclusion published. As I understand it (from as good a source as the ones quoted) the boat had been subject to a bit of "rock bashing" beforehand. The failures were unique to that model, which is (or was) very different from any other Bavaria. The builder subsequently modified all boats of the class - indeed one of the owners in the UK posted a series of photographs of the work on here at the time. So it is difficult to see how this can be used to illustrate a systematic failure amongst boats from that builder - if that is what you are trying to do.

The other link is about an earlier boat that is built in the same way as the Sigma on this thread as can be seen from the photograph and the internal damage (probably resulting from a grounding) demonstrates that the method of construction is not trouble free.

If you look hard enough you can find failures in keel hull joints - particularly fin keels from just about every designer/builder.

 

[wotayottie]

For example, as I wrote before, improper tightening sequence of keel bolts. Or the boat was lifted off the keel by someone who missed the front two keel bolts.

No way would either of those cause the front of the keel base to break off unless the keel was faulty.

 

[Tranona]

It's great that Bavaria are using keel bolts and backing plates. Problem is they ain't bolted to anything significant. But hey, as long as it looks nice.


.

What absolute rubbish! Why, when there is a serious discussion going on do some people have to make such stupid comments!

If you have something useful to contribute, do so.

For a start I suggest you read the thread properly. There has not been a survey on the Sigma in question. The OP has posted his photos commenting that he could not access the forward areas where the two short studs are, so their condition and security is unknown. The second set of photos show there has possibly been damage and repairs at the aft end, which is to be expected if the keel has impacted on something hard. Also have a look at the thread on the Sigma in Italy. The condition of the original keel studs and the spacing of the main studs does not inspire confidence about the security of attachment to the hull.

Keel problems are common on boats of this type and age, partly because of the way they are put together and partly because they often have a hard life as racing or sailing school boats.

Cannot understand the reference to wooden boats. Totally irrelevant.

The main point that I am making is that more recent boats, whether they be Bavarias or Beneteau, Hanse, Dufour etc are much better designed and built than boats of the era of this Sigma. The integrity of the bilge and keel bolt area of modern boats compared with the hotchpotch of materials and techniques used previously is but one example.

 

[Woodlouse]

What absolute rubbish! Why, when there is a serious discussion going on do some people have to make such stupid comments!

If you have something useful to contribute, do so.

For a start I suggest you read the thread properly. There has not been a survey on the Sigma in question. The OP has posted his photos commenting that he could not access the forward areas where the two short studs are, so their condition and security is unknown. The second set of photos show there has possibly been damage and repairs at the aft end, which is to be expected if the keel has impacted on something hard. Also have a look at the thread on the Sigma in Italy. The condition of the original keel studs and the spacing of the main studs does not inspire confidence about the security of attachment to the hull.

Keel problems are common on boats of this type and age, partly because of the way they are put together and partly because they often have a hard life as racing or sailing school boats.

Cannot understand the reference to wooden boats. Totally irrelevant.

The main point that I am making is that more recent boats, whether they be Bavarias or Beneteau, Hanse, Dufour etc are much better designed and built than boats of the era of this Sigma. The integrity of the bilge and keel bolt area of modern boats compared with the hotchpotch of materials and techniques used previously is but one example.

The comment about wooden boats was in reply to a different post by Snooks.

I have read the thread and I'm afraid that the pictures provided are good for speculation only. To get a decent idea you'd need a closer inspection of the keel root both at the fore and aft ends on both sides, then a good look at as many keel bolts as possible and a close examination of the laminate around the keel to look for signs of movement.

I'm afraid you're wrong about better design and build quality on modern boats. Design is ruled by a brief that'll say something like "we want two double cabins, 7 berths over all, two heads and a saloon with space for 10." Then a boat will be designed around it. The build quality of the boats is governed by how little they can possibly put into the construction and get away with it.

If you only want to do coastal cruising in light and moderate weather then boats like bavarias are fine. But I have to say personally that if I was caught in a gale offshore in a bavaria I would be absolutely bricking it.