U-Bolt deck fittings and reinforcement - Contessa 32

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martinteeluck

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Hi all,

I've heard and read a few things about deck u-bolts for the shrouds on Contessa 32's being prone to fatigue and requiring reinforcement - I'd be grateful for any comment, advice or best of all a qualified method of how to go about such a job. Being shoestring-sailors we're doing as much work as we can ourselves but require some confidence, this being a "structural" item, that we can do this job ourselves.

The mast is being taken out in a few weeks for inspection and repair (not looking forward to that one!!!) so it seems to make sense to do all deck fitting stuff we can while the mast is down.

Attached are a few pictures (we weren't guilty of painting over the fittings!!!) both inside and outside of the boat which I hope give a good impression of their current state.

View attachment 31794View attachment 31795View attachment 31796View attachment 31797View attachment 31798View attachment 31799View attachment 31800View attachment 31801

As always I look forward to any and all response from your respected hive-mind!!!

Many thanks,
Martin
 
Why not ask Jeremy Rogers? Sure he must have done that job on other boats - or the class association.
 
Which stay goes to the fitting in picture four? The backing plate looks awfully small for a back stay or cap shroud.
 
I know little about Contessa 32s but I know a bit about fatigue. Are these fittings particularly prone to fatigue? To my eye they appear to be quite well designed and I would not have predicted failure. Close inspection by eye and maybe by dye penetrant will reveal any cracks, check closely for unfair loading ( not apparent in your photos) and replace anything that doesn't look right.
 
Lazy Kipper said:
Which stay goes to the fitting in picture four? The backing plate looks awfully small for a back stay or cap shroud.
Click to expand...

Hi LK - Pictures 4 and 8 are plates for the lower shrouds (1 forward one aft) whilst 5, 6 and 7 are for the cap shroud (hope I've described that clearly!) The plates are approximately 3 x 5"

Thanks for replying,
Martin
 
vyv_cox said:
I know little about Contessa 32s but I know a bit about fatigue. Are these fittings particularly prone to fatigue? To my eye they appear to be quite well designed and I would not have predicted failure. Close inspection by eye and maybe by dye penetrant will reveal any cracks, check closely for unfair loading ( not apparent in your photos) and replace anything that doesn't look right.
Click to expand...

Hi Vyv - I've read that they are prone to fatigue and Jeremy Rogers mention them as something to watch for when buying new. I'm no expert but the loadings on and below deck don't appear to have stressed the GRP - just thought this might be a job worth doing whilst the mast is out - have you done anything like this before? DIY job?

Thanks for the response,
Martin
 
sailorman said:
I vaguely remember those short rods through the GRP web originally were round & it was recommended to add a flat surface where the shroud plate nuts fit as the round caused the nuts to break in 1/2 due to the point loadings
Click to expand...

That's correct. Our Co32 came with old U bolts which (on the cap shrouds) were bolted onto a backing cylinder which had a rounded profile. The point-loading of the nut pressing onto a rounded surface meant the nut was highly stressed and prone to cracking. We visited Jeremy Rogers in Lymington years ago and he pointed this out to us. When the nuts came off they were indeed cracked - a scary moment! could have been like that for years but it was potentially a very weak point. Looking at your photo 1072 you have exactly the same set up, and I would strongly recommend you replace it.

Jeremy supplied slightly bigger U bolts which are slightly angled to align with the cap shroud/deck angle, which are much stronger and which have a flat backing plate, not a rounded one.

If you contact Jeremy Rogers they will send you the upgraded U bolt and plates, it's a very easy job. They are slightly wider so the through deck holes will need to be widened slightly.

PM me if you need more info.

Nick
 
sailorman said:
I vaguely remember those short rods through the GRP web originally were round & it was recommended to add a flat surface where the shroud plate nuts fit as the round caused the nuts to break in 1/2 due to the point loadings
Click to expand...

Hi Sailorman - Ahhhhh, clever observation! What's your opinion of a "shaped/concave" stainless steel washer being placed between the rod and the but helping to relieve localised pressure to the nut?

Thanks for your note,
Martin
 
sailorman said:
I vaguely remember those short rods through the GRP web originally were round & it was recommended to add a flat surface where the shroud plate nuts fit as the round caused the nuts to break in 1/2 due to the point loadings
Click to expand...

Hi Sailorman - Ahhhhh, clever observation! What's your opinion of a "shaped/concave" stainless steel washer being placed between the rod and the but helping to relieve localised pressure to the nut?

Thanks for your note,
Martin
 
NDG said:
That's correct. Our Co32 came with old U bolts which (on the cap shrouds) were bolted onto a backing cylinder which had a rounded profile. The point-loading of the nut pressing onto a rounded surface meant the nut was highly stressed and prone to cracking. We visited Jeremy Rogers in Lymington years ago and he pointed this out to us. When the nuts came off they were indeed cracked - a scary moment! could have been like that for years but it was potentially a very weak point. Looking at your photo 1072 you have exactly the same set up, and I would strongly recommend you replace it.

Jeremy supplied slightly bigger U bolts which are slightly angled to align with the cap shroud/deck angle, which are much stronger and which have a flat backing plate, not a rounded one.

If you contact Jeremy Rogers they will send you the upgraded U bolt and plates, it's a very easy job. They are slightly wider so the through deck holes will need to be widened slightly.

PM me if you need more info.

Nick
Click to expand...
i sold my Co32 15 yrs ago.
the other issues are
no stringer behind the loo
bonding of the bottom of the main bulk hd
 
By the way I should have said I am going to the boat tomorrow. If you PM me your email address I will try to send you a couple of photos of our set up.
 
NDG said:
That's correct. Our Co32 came with old U bolts which (on the cap shrouds) were bolted onto a backing cylinder which had a rounded profile. The point-loading of the nut pressing onto a rounded surface meant the nut was highly stressed and prone to cracking. We visited Jeremy Rogers in Lymington years ago and he pointed this out to us. When the nuts came off they were indeed cracked - a scary moment! could have been like that for years but it was potentially a very weak point. Looking at your photo 1072 you have exactly the same set up, and I would strongly recommend you replace it.

Jeremy supplied slightly bigger U bolts which are slightly angled to align with the cap shroud/deck angle, which are much stronger and which have a flat backing plate, not a rounded one.

If you contact Jeremy Rogers they will send you the upgraded U bolt and plates, it's a very easy job. They are slightly wider so the through deck holes will need to be widened slightly.

PM me if you need more info.

Nick
Click to expand...

Hi Nick and thanks for your reply, great to hear it's an easy job and I'll get in touch with JR for some new ones.

Do you have any comment on the lower shroud plates? Are they like yours or are your own more beefy?

Thanks again,
Martin
 
The Rogers yard will supply new U bolts for the job, but they are not cheap.

In my view it would be better to source your own and do not be afraid to do the work yourself. It is simple stuff.

The original U bolts were a bit small so make sure you have gone up a size.

As Lazy Kipper has said the attachment for the lowers need bigger backing pads; many owners have taken the opportunity to fabricate L shaped brackets as well, which can then be bolted to an existing, or newly fabricated, rib. On my boat a gusset has been welded to the rear of the bracket as well. This is masive overkill, but secure.

The cap shroud fitting should not bear on a round bar (as shown I think in photos 5, 6 and 7), the new ones have a flat machined on to give a fair loading to the nut.

Have a good look at your forestay fitting as well.

The backstay is a simple thing but is easily neglected because of its tricky position. In fact I have forgotten, again, to check mine out. I must do this, and soon.
 
martinteeluck said:
Do you have any comment on the lower shroud plates? Are they like yours or are your own more beefy?
Click to expand...

The aft lowers are bolted onto a massively over-engineered L shaped bracket. The forward ones just bolt to a backing plate like yours, which I have never been happy with but keep forgetting to do anything about! I really must get them upgraded ....
 
doug748 said:
The Rogers yard will supply new U bolts for the job, but they are not cheap.

In my view it would be better to source your own and do not be afraid to do the work yourself. It is simple stuff.

The original U bolts were a bit small so make sure you have gone up a size.

As Lazy Kipper has said the attachment for the lowers need bigger backing pads; many owners have taken the opportunity to fabricate L shaped brackets as well, which can then be bolted to an existing, or newly fabricated, rib. On my boat a gusset has been welded to the rear of the bracket as well. This is masive overkill, but secure.

The cap shroud fitting should not bear on a round bar (as shown I think in photos 5, 6 and 7), the new ones have a flat machined on to give a fair loading to the nut.

Have a good look at your forestay fitting as well.

The backstay is a simple thing but is easily neglected because of its tricky position. In fact I have forgotten, again, to check mine out. I must do this, and soon.
Click to expand...

Hi Doug - I'd forgotten about fore and aft! Will check them out and thanks for your post, Martin.
 
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