Bavaria 39 keel problems

jimmy_the_builder

jimmy_the_builder

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Afternoon all, I realise as a fully paid-up member of the mobo gang I am treading on hallowed ground here - but I need some urgent raggie assistance. A very good chum of mine has a Bavaria 39 which he's owned since new (2005). The boat's just been lifted for a bit of annual below-the-waterline love - and he's been given the slightly scary news that the keel is apparently separating from the hull, yikes.

Anyway - what would be _really_ good, if possible, is to hear from any other Bav 39 owners - especially anyone who has the larger keel fitted. Anybody out there?

Yours very gratefully from the dark side
Jimmy
 
jimmy_the_builder said:
Afternoon all, I realise as a fully paid-up member of the mobo gang I am treading on hallowed ground here - but I need some urgent raggie assistance. A very good chum of mine has a Bavaria 39 which he's owned since new (2005). The boat's just been lifted for a bit of annual below-the-waterline love - and he's been given the slightly scary news that the keel is apparently separating from the hull, yikes.
Click to expand...

How has he heard? If it hasn't already been done, he needs to get a surveyor - a good surveyor, and one who knows this type of boat - onto the case pronto. If you let us know where the boat is, someone here may well be able to recommend a surveyor.

If it was the Clyde, for example, then I'd recommend Ian Nicholson because he's a very experienced naval architect as well as a surveyor and will probably have a much better idea of what rectification work might be needed/possible than someone whose professional life is kicking the tyres for insurance companies. OK, that's a bit cruel, but if there is a serious structural problem your pal needs someone with serious yacht design experience to look at it.

Good luck, and sympathies.
 
Depends a great deal as well on what is meant by 'seperating from the hull'..... it could be from the keel bolts need renewing/tightening through to the hull is delaminating around the keel box..... as said above.... a surveyor needs to identify what the actual problem is

PS.... its not unknown for the mastic around the joint to deteriorate, and for an inexperienced eye to mistake this for failure...... so it might not be anywhere near as bad it sounds at face value
 
jimmy_the_builder said:
Afternoon all, I realise as a fully paid-up member of the mobo gang I am treading on hallowed ground here - but I need some urgent raggie assistance. A very good chum of mine has a Bavaria 39 which he's owned since new (2005). The boat's just been lifted for a bit of annual below-the-waterline love - and he's been given the slightly scary news that the keel is apparently separating from the hull, yikes.

Anyway - what would be _really_ good, if possible, is to hear from any other Bav 39 owners - especially anyone who has the larger keel fitted. Anybody out there?

Yours very gratefully from the dark side
Jimmy
Click to expand...

As everyone else says, surely a job for a decent surveyor.

Is it really as bad as he's been told. It's a newish boat and it seems a bit odd (but probably not impossible) that he didn't notice any water ingress as the problem developed.
 
Talulah said:
You might find this post interesting.
http://www.ybw.com/forums/showthread.php?t=177477
Click to expand...

Ignore the video, that was for a Match that run aground.

Assuming that your mate never run aground and the play is minimal (measurable in less than 2mm) it might be as simple as re-torquing the keel bolts. It may be necessary on boats like Bavaria/Beneteau and the like which use galvanized steel bolts instead of stainless steel. Even more so if embedded in a lead keel which is softer than steel and hence tends to settle with time.
 
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Thanks for all the replies. Here's the current situation, as I understand it:

- boat was lifted in Gosport last week
- when lifted, the boatyard guys noticed the gap at the aft end of the keel
- the gap is max 12mm, and runs forward about 300mm from the aft end of the keel
- when they settle the boat down on the keel, the gap closes - so it very much looks like a failure, rather than a static gap that might normally be filled with mastic
- on the boatyards advice, a surveyor was instructed
- the surveyors initial inspection is suggesting that there is no aft keel bolt; the big question is: is this by design, or not...

So: what would be really helpful would be to hear from any other bav 39 owners to see what the aft keel bolt arrangements _should_ be. My chum is along to have a look at the problem for himself first-hand tomorrow, so time is of the essence.

Thanks again for the replies. Appreciate any further advice.

Cheers
Jimmy
 
Is the boat a 39 Cruiser? What keel type? Deep Lead? The aft of the keel does have keel bolts, but of course not to the very tip. If it is so much detached some must have failed. Was there any water ingress?

Normally the keel is also glued to the hull. The mastick used is so powerful that if one WANTS to remove the keel, fiberglass delamination form the hull may occurr. Some keels even remain attached once all the bolts have been removed. Has this happened or is there a clean separation without delamination? If there is a clean separation the best course of action will be:

1) remove the whole keel (paying attention that no damage occours because of the glue (see above)
2) clean hull and keel top
3) check every bolt carefully
4) replace (if possible) or straighten any damaged/bent bolt
5) refit with new mastick and new nuts.
6) torque appropriately

If (1) is not possible, then just clean, inject new mastick (boat on slings), re-torque (boat on cradle) and pray (boat in the water and heeling).
 
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Bav Keel Bolts

I find this very difficult to believe, Bav keel bolts are massive stainless jobs, the design is somewhat over engineered.
This would not have happened in one season, surely it would have been noticed last time out of the water.
Seems to me there is something else going on here. If there is a bolt missing there will be a hole for it in the hull.
 
haydude said:
Is the boat a 39 Cruiser? What keel type? Deep Lead? The aft of the keel does have keel bolts, but of course not to the very tip. If it is so much detached some must have failed. Was there any water ingress?

Normally the keel is also glued to the hull. The mastick used is so powerful that if one WANTS to remove the keel, fiberglass delamination form the hull may occurr. Some keels even remain attached once all the bolts have been removed. Has this happened or is there a clean separation without delamination? If there is a clean separation the best course of action will be:

1) remove the whole keel (paying attention that no damage occours because of the glue (see above)
2) clean hull and keel top
3) check every bolt carefully
4) replace (if possible) or straighten any damaged/bent bolt
5) refit with new mastick and new nuts.
6) torque appropriately

If (1) is not possible, then just clean, inject new mastick (boat on slings), re-torque (boat on cradle) and pray (boat in the water and heeling).
Click to expand...

Thanks for this. I don't know what the keel type is (he described it to me as the 'large keel', which I took to mean that there was some choice about keel size at the point of order); I'll ask the question when I speak to him again later this evening. However - I do know that there's been no water ingress, cos he mentioned this specific point when we spoke earlier on, and I forgot to put it in my last note.

Cheers
Jimmy
 
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BoyBlue49 said:
I find this very difficult to believe, Bav keel bolts are massive stainless jobs, the design is somewhat over engineered.
This would not have happened in one season, surely it would have been noticed last time out of the water.
Seems to me there is something else going on here. If there is a bolt missing there will be a hole for it in the hull.
Click to expand...

This is a good point, and one I thought of myself. If there is or was an aft keel bolt, one presumes that if was to become loose, it would do so over a period of time.

However - if the bolt is absent, then presumably you could get a more sudden failure? I should hasten to add that this is speculation by me. Until we know what the keel bolt arrangement _should_ be, then it's hard to figure out what's missing (or not) on this boat.

So: lonely Bav 39 owner, GSOH, seeks similar for 'I'll show you my keel bolts if you show me yours' type activities...

Thanks again for the replies.

Cheers
Jimmy
 
haydude said:
Is the boat a 39 Cruiser? What keel type? Deep Lead? The aft of the keel does have keel bolts, but of course not to the very tip. If it is so much detached some must have failed. Was there any water ingress?

Normally the keel is also glued to the hull. The mastick used is so powerful that if one WANTS to remove the keel, fiberglass delamination form the hull may occurr. Some keels even remain attached once all the bolts have been removed. Has this happened or is there a clean separation without delamination? If there is a clean separation the best course of action will be:

1) remove the whole keel (paying attention that no damage occours because of the glue (see above)
2) clean hull and keel top
3) check every bolt carefully
4) replace (if possible) or straighten any damaged/bent bolt
5) refit with new mastick and new nuts.
6) torque appropriately

If (1) is not possible, then just clean, inject new mastick (boat on slings), re-torque (boat on cradle) and pray (boat in the water and heeling).
Click to expand...

He was just on the phone. Yes it is a deep lead keel.

HD you seem to be well-informed about this, are you a Bav 39 owner?

Cheers
Jimmy
 
JTB - it seems odd that the separation is taking place only over the 300mm from the after end. It's impossible for the keel to articulate over the length of the join, so it must be the hull flexing upwards as she is lifted.

The technical term is sagging, BTW.
 
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sarabande said:
JTB - it seems odd that the separation is taking place only over the 300mm from the after end. It's impossible for the keel to articulate over the length of the join, so it must be the hull flexing upwards as she is lifted.

The technical term is sagging, BTW.
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Yep. If I was guessing (and bearing in mind that as a mobo-er I've got no direct experience of this sort of thing) my presumption would be that the extra-heavy lead keel + alleged absence of aft keel bolt = remainder of keel fixings causing hull sag as described.

What isn't clear is whether there _should_ be another keel bolt there - or if there's a different (and much more serious) problem going on like insufficient strength in the hull lay-up.

Poor bloke though - he's been given a worst-case repair cost, which I'm not at liberty to share here - but it's a pretty scary number.

Cheers
Jimmy
 
I would be tempted to look at another Bav with similar spec thats up for sale and count/compare the keel bolt arrangement. While I think its unlikely as Bav QA is quite good you must eliminate that the last one or two keel bolts were completely omitted. Personally I cannot imagine how as most of build it done by template and I assume all the keel bolts are drilled automatically on a rig?

From what I have read on here and heard from a friend that grounded their Elan 33 while racing the damage appears similar. GRP can flex a lot and show no/little sign of distress. I have seen all the galley timber shattered by what was obviously well over 2" of collision movement yet only 100mm x 150mm patch on the side was crazed.

I would see if the surveyor will offer an opinion as to grounding damage as it would then be covered by insurance surely.

Better an insurance claim than trying to prove inadequate build quality by Bavaria after all they are one of the most prolific production boat manufacturers and apart from the "apparent" Match keel connection under design, they are durable boats that have stood up well to heavy charter use/abuse!
 
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Hi there Jimmy,
I too have a Bavaria 39 Cruiser displaying the same symptoms. Mine is a 2005 build lead keel. I first observed the movement of the trailing edge at the first liftout one month after launching. My crack is only aft of the last keel bolts.
I will try to attach the bolting arrangement as a Bavaria drawing and photos of a partial solution. Compare your bolt arrangement and I think you will find it to be the same - no broken or missing bolts just too big a distance from the keel bolts to the aft edge.
The lead keel has 10 off M20 bolts and the aft pair is some 300mm forward of the trailing edge. This appears to be too far away and an additional bolt would help at the aft edge of the frame. (This occurs in the Cast Iron keel design) When lifted in the slings mine flexed to open a 10mm to 12mm gap. In the water the gap is more like 5mm (the keel weighs less in the water).
The keel centre of gravity is nearer the aft bolts than the forward bolts thus loading the aft bolts more.
I believe that when the boat is lifted in the slings the hull flexes down and opens a gap between the hull and keel at the aft edge. This looks somewhat alarming but I have been watching this for 6 years on mine and no other symptoms have appeared and it has not increased.

What I have done is:
1. When the boat is sitting on the keel, tighten the keel bolts. Mine were loose.
2. Installed 10mm st st plates between the frames and epoxied into the hull to take the bolts. The photo shows the preparation and the plate sitting nearby before glueing in.
3. Lifted the hull in the slings, cleaned out the gap then filled with sikkaflex and allowed to set overnight before launching. This has filled the gap and squeezes the sikka when the boat is set on the keel (at the next liftout).

The aft bolts are through the forward reinforcing of the frame. This loads the frame assymetrically and has it twist and exaggerate the gap.
Some might say that this amout of movement is un acceptable but I think it is tollerable if there are no other symptoms. I am satisfied that no water is entering the area of the bolts on my boat. There is no other cracking of the keel joint.
If you want to do more I think that keel removal is the only next step and I have a yacht designers procedure for re fitting the keel to stop the gap happening.
PS, I think I have added two photos but the drawing is 97kb of pdf which I have failed to attach. PM me for a copy or can someone else help me post the pdf

Andrew
 
EyeCandy said:
Hi there Jimmy,
I too have a Bavaria 39 Cruiser displaying the same symptoms.
Click to expand...

Hi Andrew

Thanks for your long and very informative post. Your second photo looks _exactly_ the same as the photo's I've seen this evening of my friends boat. I've also seen photos from the same model of boat, only fitted with the cast iron keel - and you're exactly correct, it has a final keel bolt very close to the trailing edge of the keel.

In your step 2 - do you mean that you have installed the additional s/s plates to receive the _existing_ keel bolts? (Ie to reduce the degree to which the weight of the keel can cause the hull to sag)

I'll pm you now to get your pdf. Thanks once again.

Cheers
Jimmy
 
From what I've read an additional pair of bolts near the trailing edge of the keel would be good but in this case that's not possible.The main reason for the detachment for want of a better word is that the structure is not rigid enough to take the load to the last bolts so it has to be beefed up.Another floor glassed in where the flexing is occuring might do it but the whole thing must be well thought out to prevent point loading.The grid structure on Bavs is quite strong so it should a simple matter of adding another floor with two or even one logitudinal stringer connecting it to the existing floor.
Something like this.
floor.jpg

If it were my boat I wouldn't loose sleep over it .I know because I've done it before and it works.
 
I believe Opal paid for the hulls of the Bavaria Matches to be strengthened. I presume they got some payment from Bavaria for that. I know in one case the work was done by Opal and it certainly wasn't paid for by the owner of the boat.

If this is a general fault with the Bavaria 39, presumably there would be a similar arrangement (albeit not through Opal as they don't exist anymore). It may require a bit of twisting of Bavaria's arm.

It would be very handy if you could find out what is happening in other countries.
 
Seems a bit rubbish if they haven't altered the spider moulding to take into account the different bolt pattern on the lead keel; poor show.
 
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