I have a 400e whose keel has developed some rust and a crack where the lead portion meets the steel portion. Also note some rust at the hull-keel joint. Is the fix just a matter of using a wire brush, some kind of anti-corrosive, and some epoxy, or do I need to plan for shot blasting, re-fairing, and a few months out of the water? Pics below.

Starboard

Port

Leading Edge

Trailing Edge

Seen boats with way worse.

Hi Dan - and welcome to the forum

A few informations about your boat, like model year and number, how long you have owned her, the interval between renewal of the bottom paint and so on ................. - would be nice.

Try Search->Advanced search->All forums->Any Date and "Keel" or "Keel Damage", and you will find a lot of previous posts.

The big craters with rust in the cast iron surely haven't developed after one year in the water? If so, there must be a fault in the moulding. I remember a post in myhanse where an owner had to replace the lead part of the keel, because the moulding at the top of the lead was filled with debris. Find his story via the search function.

In my opinion, the worst damage is the crack where cast iron and lead are connected. It seems that the lead part can move just a little bit, and this can result in metal fatigue in the bolts. Do also read the post about the serious problem if seawater is trapped in an oxygen-deprived environment. https://www.myhanse.com/damaged-keel_topic12359_page1.html?KW=keel

Be sure, that any repair (like an angle-grinder removing rust in the iron/lead connection) will ensure, that the lead part of the keel is rock steady.

: Kjeld

P.S.: The bolts at the top are not like on my H400. I have 10 M42 bolts, 2x4 in a quadrant, and 2 in line. (This drawing is from a H370 from 2006).

The broker had had the bottom anti-fouled last January-ish, but he admitted it was the cheapest he could find. None of the damage to the keel in the photos was evident then, but it appears there was an extra thick coat of anti-foul at the separation line. The surveyor (I found the best respected in the region) said that he suspected the fairing had come loose on the keel but noted no reason to be concerned as true damage would be spectacular and obvious.

I have had a littlte rust on the cast iron too, and just cleaned off the rust and applied some Hammerite anti-rust paint. In your case, a bit of filler afterwards also will be needed.

Regarding the connection between cast iron and lead, I would email the photos of the crack to the surveyor, and ask if it will be okay to clean the crack with an angle-grinder with a thin disk, and then apply "filler with high compressive strenght" in the connection.

When the boat is heeling, there is a substantial force trying to widen the crack. (And trying to induce metal-fatigue in the keel bolts).

You should read the posts here at myhanse about grounding. The fact that the crack in your keel is wider in the front of the keel, could be because it suffered an impact from grounding.

If no repair is made in the bottom front of the keel, it still could have happened, since a grounding in a sandy bottom leaves little damage.

It will be wise to check for hairline cracks in the fibreglass around the keel  bolts inside the boat.

I own a H400 myself, and the fastening of the keel to the bottom is very sturdy. Also the keel bolts are in a reassuring size. If you ever have seen the size of the keel bolts on a (insert name of a cheaper German yacht), you know what I am talking about.

Good news is that it’s not a heavy structural repair (though advice about the bulb bolts above is a worthwhile check). Just cut back, let it dry, treat the iron, re-fibreglass, fair and epoxy. 

On ours, the start of the issue was a lobster pot that thumped into the keel when we caught it’s line. Noticed it at next haul out. It was a 9 inch band of repair work but easy to do. I got in a good professional I know as getting resin to adhere correctly is a bit of a black art and just played helper for this job. Note even on an ‘epoxy’ hull boat the keel is covered in polyester resin! Hanse marketing never mentioned that :-)

Inspiration Marine also deserve a big thank you for remote advice and support to confirm the repair plan logic.  

Mark

Where did you source the schematic's of the keel and what year and version of Hanse is it for?

cheers

Technical drawings of Hanse keels are on:

 https://hanse.boatoon.com/en/search?order=score&p=1&search=keel

 - but you will only find the keels in stock by boatoon. If you need a special drawing, email boatoon for it.

The drawing above is for a Hanse 370 year 2006, where the total weight of the keel is 2188 kg, and the draught 1,95 meters. My H400 (2006) has a 10% longer mast (19,52m) and a 1,98 meter heavier steel/lead keel with a total weight of 2915 kg.

The iron part of the keel on my 400 is fastened to the hull with 10 pieces of 42mm bolts in galvanized steel which is stronger than stainless steel. The H370 (see drawing) has bolts in 42/36/24mm since the keel is 727 kg lighter. Be aware, that the double bolts are not apparent in the H370 drawing, since no top view is shown.