I am in process of buying a 2000 Moody 46 and today I put down an offer/deposit and will have professional survey done later this week. I have found couple of issues that I would love anyones opinion and expertise. I found a crack that runs horizontally next to where mast is bolted in and some rusty keel bolts see pics. Are these two issues a deal breaker? thank you in advance.
Moody 46 2000 Moody 46 Open
- Thread starter Hani Esoo
- Start date
- Status
- MOA Position
- East Coast Captain
- Boat name
- WILD THYME
- Berth
- Suffolk Yacht Harbour
- Boat type
- Moody 425
- Cruising area
- North Sea, English Channel, Biscay
Hi Hani and welcome to the MOA,
It's hard to be sure about the crack from a photo, it could be simply a crack in the flow coat Marine Projects used to paint over the bilges in these boats or it could be something more significant. I would want to grind it out to see whether it penetrates to any depth or is just at the surface, I would certainly draw it to the attention of your surveyor.
The rusty keel studs and nuts are often found on Moodys as they used carbon steel for these parts, which inevitably rusts if sea water gets jnto the bilge (e.g. from cleaning the log impeller). In cases where the studs have been drawn, it's always found that the rusting is limited to the oart exposed in the bilge, provided the keel to hull joint has not failed admitting seawater to the lower part of the stud from outside. This rusting always looks a lot worse than it is and can often be remedied by cleaning them up with a wire brush and protecting with a tough rust tolerant oaint like Hammerite.
The nut in your final photo looks as though it might have lost a lot of material, again hard to be sure until it's cleaned up. In such cases it's possible to split the nut off and replace with new. If doing this, take care not to disturb the stud unless you plan to change that as well, in which case you will need to reseal the stud in its hole. If you're keeping the original stud, replace the nut in the same material to avoid galvanic corrosion.
You will often find that younger surveyors, used to stainless steel keel studs, are thrown by this rusting , but it is relatively easy to deal with and much advice is available in the MOA, if you join us.
Hope the purchase goes well for you and look forward to seeing you as a member.
Peter.
It's hard to be sure about the crack from a photo, it could be simply a crack in the flow coat Marine Projects used to paint over the bilges in these boats or it could be something more significant. I would want to grind it out to see whether it penetrates to any depth or is just at the surface, I would certainly draw it to the attention of your surveyor.
The rusty keel studs and nuts are often found on Moodys as they used carbon steel for these parts, which inevitably rusts if sea water gets jnto the bilge (e.g. from cleaning the log impeller). In cases where the studs have been drawn, it's always found that the rusting is limited to the oart exposed in the bilge, provided the keel to hull joint has not failed admitting seawater to the lower part of the stud from outside. This rusting always looks a lot worse than it is and can often be remedied by cleaning them up with a wire brush and protecting with a tough rust tolerant oaint like Hammerite.
The nut in your final photo looks as though it might have lost a lot of material, again hard to be sure until it's cleaned up. In such cases it's possible to split the nut off and replace with new. If doing this, take care not to disturb the stud unless you plan to change that as well, in which case you will need to reseal the stud in its hole. If you're keeping the original stud, replace the nut in the same material to avoid galvanic corrosion.
You will often find that younger surveyors, used to stainless steel keel studs, are thrown by this rusting , but it is relatively easy to deal with and much advice is available in the MOA, if you join us.
Hope the purchase goes well for you and look forward to seeing you as a member.
Peter.
Thanks for the response Peter, the crack is actually deep into the stringer and I am wondering if it was grounded at one point.
- MOA Position
- East Coast Captain
- Boat name
- WILD THYME
- Berth
- Suffolk Yacht Harbour
- Boat type
- Moody 425
- Cruising area
- North Sea, English Channel, Biscay
Hi Hani,
A crack going deep into a stringer is, imho, a cause for concern and something on which I would seek the advice of a surveyor or an experienced shipwright.
One possible route is to get a realistic estimate for a professional repair and offer that amount below the asking price. That, if accepted, is a major help, but doesn't remove the risk of greater damage being revealed when the job starts.
Peter.
A crack going deep into a stringer is, imho, a cause for concern and something on which I would seek the advice of a surveyor or an experienced shipwright.
One possible route is to get a realistic estimate for a professional repair and offer that amount below the asking price. That, if accepted, is a major help, but doesn't remove the risk of greater damage being revealed when the job starts.
Peter.
- MOA Position
- East Coast Captain
- Boat name
- WILD THYME
- Berth
- Suffolk Yacht Harbour
- Boat type
- Moody 425
- Cruising area
- North Sea, English Channel, Biscay
Hi Hani,
I'm not sure what you mean by a schematic of the boat. The association do not have any drawings that I am aware of, but I guess her designer
(and MOA President), Bill Dixon, has.I assume he can be contacted at his business:
Dixon Yacht Design, Unit 16, The Boatyard,
Swanwick Marina, Swanwick,
Southampton, United Kingdom, SO31 1ZL
+44 (0)1489 572337
info@dixonyachtdesign.com
It would be interesting to know whether he is prepared to share a copy of the lines,
Peter.
I'm not sure what you mean by a schematic of the boat. The association do not have any drawings that I am aware of, but I guess her designer
(and MOA President), Bill Dixon, has.I assume he can be contacted at his business:
Dixon Yacht Design, Unit 16, The Boatyard,
Swanwick Marina, Swanwick,
Southampton, United Kingdom, SO31 1ZL
+44 (0)1489 572337
info@dixonyachtdesign.com
It would be interesting to know whether he is prepared to share a copy of the lines,
Peter.
Peter Rigby
Temporary Member
There are numerous threads on the topic of mild steel Vs stainless 316 for the studs and nut/backing plate assemblies with apparently no definitive answer.
The use of carbon steel for the studs seems to make sense to avoid crevice corrosion, but the Achilles' heel being the corrosion of the nuts and studs that are typically exposed to sea water in the bilge.
I was wondering whether a hybrid solution might make more sense. i.e. Use carbon steel for the studs and 316 for the backing plates and nuts. To limit the chances galvanic corrosion one could use an anti-corrosion compound such as Duralac. If such compounds are effective on masts between steel rivets and aluminium alloys, they should surely provide the protection necessary at the interface between stud and nut in the bilge ???
The use of carbon steel for the studs seems to make sense to avoid crevice corrosion, but the Achilles' heel being the corrosion of the nuts and studs that are typically exposed to sea water in the bilge.
I was wondering whether a hybrid solution might make more sense. i.e. Use carbon steel for the studs and 316 for the backing plates and nuts. To limit the chances galvanic corrosion one could use an anti-corrosion compound such as Duralac. If such compounds are effective on masts between steel rivets and aluminium alloys, they should surely provide the protection necessary at the interface between stud and nut in the bilge ???
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- MOA Position
- East Coast Captain
- Boat name
- WILD THYME
- Berth
- Suffolk Yacht Harbour
- Boat type
- Moody 425
- Cruising area
- North Sea, English Channel, Biscay
Hi Peter,
I don't think this board, headed for NON-TECHNICAL questions is the place for a highly technical discussion of the ways in which various metals corrode and how to prevent that. Suffice to say that crevice corrosion in an anoxic chloride contaminated environment is not unique to austenitic steels so ferritic or carbon steels can suffer that and the performance of chromate pastes in protectng against electrolytic action between aluminium in steel provides no argument for it protecting against chemical corrosion of steels.
I would not recomend mixing metals in the way you propose some prefer to use a chloride tolerant austenitic stainless steel and others prefer to use the original Moody carbon steel approach. I appreciate the arguments for both. I would also note that the vast majority of yachts built in the past 30 years use type 316 (A4) stainless steel sruds or bolts where the keel is of a bolted on design. While the incidence of keels coming off boats has increased in that period, none of these events which have been technically investigarec find bolt or stud failure to be the cause. You can add to that the fact that the Moody keel attachment design is very conservatjve compared to most modern yachts where the joint is much shorter leaving less space for studs and you might understand why I'm personally happy with either material fof the studs nuts and backing plates and see no reason to mix the materials.
Peter.
I don't think this board, headed for NON-TECHNICAL questions is the place for a highly technical discussion of the ways in which various metals corrode and how to prevent that. Suffice to say that crevice corrosion in an anoxic chloride contaminated environment is not unique to austenitic steels so ferritic or carbon steels can suffer that and the performance of chromate pastes in protectng against electrolytic action between aluminium in steel provides no argument for it protecting against chemical corrosion of steels.
I would not recomend mixing metals in the way you propose some prefer to use a chloride tolerant austenitic stainless steel and others prefer to use the original Moody carbon steel approach. I appreciate the arguments for both. I would also note that the vast majority of yachts built in the past 30 years use type 316 (A4) stainless steel sruds or bolts where the keel is of a bolted on design. While the incidence of keels coming off boats has increased in that period, none of these events which have been technically investigarec find bolt or stud failure to be the cause. You can add to that the fact that the Moody keel attachment design is very conservatjve compared to most modern yachts where the joint is much shorter leaving less space for studs and you might understand why I'm personally happy with either material fof the studs nuts and backing plates and see no reason to mix the materials.
Peter.
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- Boat name
- CANTATA
- Berth
- East Coast
- Boat type
- Moody 36(90s)
- Cruising area
- East Coast France Belgium Holland
I'm closing this thread at this point for the reasons that Peter Wright outlines above.
Hani, please start a new thread if needed, if you have still not bought your Moody and have further queries.
Peter (Rigby), do please start a new thread in the Technical Forum if you want to pursue your query on mixed metals further.
Thank you!
Hani, please start a new thread if needed, if you have still not bought your Moody and have further queries.
Peter (Rigby), do please start a new thread in the Technical Forum if you want to pursue your query on mixed metals further.
Thank you!
- Status