Rudder rebuild - Moody

MightyWalrus

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Concerned that there's moisture in our rudder and considering a rebuild. Anyone able to advise on the cost of rebuilding a large rudder? (Moody 47). Recent survey came back 'ok'. Hull is totally fine but there are suspect blisters on the rudder face (yeah, I popped a few... not good) and a tiny but persistent drip when hauled out. Think the time has come ....... Thanks for any feed back.
 

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I had a similar issue but on a smaller vesselI of 10.8m guess it varies geogrphically but at say Hayling island you might be looking at around £ 800 if you are asking for price a contractor might charge to drop out take away, fix and resinstall.
 
Are you a member of the Moody Owners Association? (MOA) Lots of technical info and probably someone who has specific information on your model.
 
Do you know what the rudder is made of?

When I made mine up I welded X3 tangs to the rudder stock then shaped marine ply over the tangs and butted up against the rudder stock. All gluing was with epoxy glue and gaps/hollows were filled with epoxy filler. Finally the whole rudder was covered with x 4 layers of epoxy and glass cloth.

If water did find its' way into the rudder I wonder what harm it would do? I wonder what yours is made of?
 
Are you a member of the Moody Owners Association? (MOA) Lots of technical info and probably someone who has specific information on your model.

+1 Best place to get help.

A few blisters on a rudder are not unusual and my first step would be to drill a hole in the bottom to see just how much water comes out, I wouldn't worry about a small amount provided no sign of delamination anywhere. Hole can later be filled with epoxy and blisters dug out, cleaned, dried and filled.
 
Agree with Graham though not so sure about the level of technical help available on MOA (I am a member) and use it a lot. Owned three boats from Marine Projects and water in the rudder is not that uncommon, I used to drain our Sigma 33 every winter. It seemed to get in at the joint between the shaft and the moulding so not that easy to prevent, we just drilled a hole in the bottom at lift out and plugged it before going back, if it is about half a litre lying in the bottom of the void it is not doing much harm.
 
Agree with Graham though not so sure about the level of technical help available on MOA (I am a member) and use it a lot. Owned three boats from Marine Projects and water in the rudder is not that uncommon, I used to drain our Sigma 33 every winter. It seemed to get in at the joint between the shaft and the moulding so not that easy to prevent, we just drilled a hole in the bottom at lift out and plugged it before going back, if it is about half a litre lying in the bottom of the void it is not doing much harm.

MOA search shows up quite a few rudder rebuild threads but nothing on that particular model of boat. It is however a standard rudder design used on many models such as my 376.
 
The rudder on my 1978 Rival was a bit damp with small bubbles on the surface. I opened up some inspection panels and confirmed that the stainless of the tangs and the welds to the rudder shaft were pristine (cue mutterings under my breath along the lines of ... why did I bother...). Inspection panels replaced and a couple of coats of epoxy added after a winter dry-out. As already flagged, my yard also recommended a hole drilled into the base of the rudder at haul out, seems to do the job.
 
I rebuilt a friends rudder after a grounding which broke half of it off, a Westerly Longbow, but most rudders are similar construction, I enjoyed the job but it took a lot of time and workshop space, the materials cost around £100 inc. epoxy resins at the time, but I had a lot of foam board, mat and rovings left over. It would be faster starting from scratch and using polyester resin which goes off faster and is not as temperature sensitive.
Jefa sell ready made rudders but they are modern deep spades, their website is good and worth a look if contemplating a project like this.

Chris Owen'a very experenced sailmaker told me that nearly all yacht rudders would work better if the aerofoil profile was fatter this would also make them stronger. I considered doing it on our Finngulf but it was easier to add a flange with similar effect. If that is accepted it provides the option of drying out and overlaying a rudder rather than replacing the whole thing?
 
This is great, thanks so much for the advice and feed back, just applied to join the Moody Association too. Much of whats written above rings true with my gut feeling, which is that it's probably ok. Some great feed back. Thank you everyone !
 
@MightyWalrus ; did you make any progress on this? I own a 1985 M47 as well (currently hauled out in Mexico) and thinking about dropping the rudder to take a look at it. Any info you already gathered would be awesome! :)
 

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Concerned that there's moisture in our rudder and considering a rebuild. Anyone able to advise on the cost of rebuilding a large rudder? (Moody 47). Recent survey came back 'ok'. Hull is totally fine but there are suspect blisters on the rudder face (yeah, I popped a few... not good) and a tiny but persistent drip when hauled out. Think the time has come ....... Thanks for any feed back.
Many rudders contain moisture. It gets in via the stock. Has it been verified in your case or are you relying on a moisture meter reading? Is it a safety risk? Most likely not. Theoretically the tangs that secure the blade to the stock could corrode but how many cases of this are reliablely on record?

You need solid evidence of need before you spend hundreds to get the blade split, checked out and rebuilt. You will not feel good if no work apart from a blast from a drier is required.

When you've rebuilt your rudder at great cost and effort, chances are it will show moisture before long.

PWG
 
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