MERLIN ROCKET FORUM

Topic : Deck Repair advice needed

Hi all

I'm looking for a bit of guidance and advice on repairs!

Spent 5 hours in our Rocket on Saturday for a 5 hr race in aid of the RNLI... as I'd only spent about 3 hours on and off in it up until then I didn't realise just how hard it would be!

Unfortunately due to high winds and incorrect helm placement, it's developed a bit of a split/crack on the one side deck. On Friday night during training we heard a crack, and the inner slope of the deck had split slightly, by the end of a challenging race on Saturday that split was 5 feet long, and goes up pretty much the length of the side of the boat. The split goes between the two blue straps indicated in the first photo.

Photos:

http://www.cautionwater.com/uploads/MerlinDamage/_5095054.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095056.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095057.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095058.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095059.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095060.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095062.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095064.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095066.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095068.jpg
http://www.cautionwater.com/uploads/MerlinDamage/_5095070.jpg

Need some advice on fixing - whether it's doable to fix it myself, as the only load this wood really bears is me (and the jib sheet cleat, although we're now sheeting straight from the barber hauler block on the floor). It is a clean split between three pieces of wood, it's not cracked across it.

I want this done properly (i.e. ideally not by me) so any advice on where to take it and guestimates as to how much I'm looking at to get it repaired would be appreciated.

I'm based in the Midlands (near Dudley). Another chap racing against us, Graham Pope of Severn Sailboats recognised it as a Smoker's and has worked on them before, so he's an option, would like some other possibilities though!

For anyone who's interested, it's 3146 Sledgehammer, recently purchased from a chap at Bala Sailing Club, and now relocated to Himley Hall SC in the Midlands (small Merlin fleet of one).


Posted: 13/05/2010 00:46:27
By: Richard H
Hi Richard,

Basically with your boat being an old girl it looks like the glue (cascamite) has failed along the join. To repair it is a pretty simple task and very doable by you. Get yourself a hack saw blade, open the join rake out all the old glue and then if you can open up the join as much as you can by using something like thick but narrow wooden wedges. Once you have done this mix up some epoxy resin something like SP320 or 106 (comes in 1kg packs or you can by the small SP handy packs)a then once you have thoroughly mixed the epoxy add some micro fibfres to create a nice thick paste (West do a good fibre mix called Filleting Blend this, when mixed, comes up pretty much the same colour as the wood whereas SP Microfibres is more a whiteish colour) anyway,apply the epoxy mix to the crack and then clamp together remebering to remove excess epoxy. This can be done by running a very sharp knife or chisel along the join. It would also be worth while putting some wide masking tape either side of the join as this will stop the epoxy going all over the good wood. Once cured 24/48 hours in good warm try environment, rub back, make good and add several coats of varnish. If you go back to bear wood then it might be worth adding a couple clear coats of epoxy over join and wood before varnishing to give extra strength. Good luck.

http://www.sailboats.co.uk/Cat~Epoxy_5187.html

Posted: 13/05/2010 09:06:35
By: Richard Battey
Exact same thing happened to me in 3245. I hear from other people that it is just the Cascamite glue giving up after 30 years!

She will be good as new with epoxy, don't worry. A professional will do the job so that there is no sight of the original problem. Laurie Smart made a beautiful job of my inwhales, but he is probably too far south for you (Horsham). Someone else will recommend a Midlands boatbuilder shortly...


Posted: 13/05/2010 09:06:36
By: Mags
loads of spelling and grammar mistakes but hey I havent had a tea yet and it is only 9am!;-)


Posted: 13/05/2010 09:09:05
By: Richard Battey
I did this on my last boat and the fix was quite easy - after making sure its all dried out, I scraped out the old glue carefully with a scalpel or stanley knife so there was no loose stuff left in the crack.  Put masking tape along each side of the crack as close as I could to the gap, then squeezed epoxy into the gap until it started coming out of the back. You then need to clamp it up as best you can.  When the epoxy was starting to cure and was just getting hard, I took the masking tape off leaving just a small line of epoxy to tidy up with a sharp blade. I went on to put small extra knees between this loose piece of inner deck and the inside of the top plank so it didn't happen again.
I think Phil Scott near Sutton Coldfield would be the logical choice of repairer - sorry I don't have his number to hand.
Hope this helps.


Posted: 13/05/2010 09:18:31
By: KM
LOL, lots of good advice already in the time it took to write my reply - sorry for the duplication!


Posted: 13/05/2010 09:20:13
By: KM
When clamping up an epoxied joint remember to use a piece of plywood or the like to prevent the clamp damaging the wood on the boat.  It's amazing how those little circles of crushed wood will show up.  BUT to prevent the ply getting stuck to the boat witha bit of stray epoxy just put a piece of the brown plasic self adhesive tape over the ply.  Epoxy won't stick to the shiny surface.  To clear away excess after it has set heat a chisel up with a heat gun - pretty hot and it will pare it off like a knife through butter.


Posted: 13/05/2010 09:28:27
By: Garry R
Agree entirely with what has already been said but just to say the splitting and cracking is a bit more fundamental and structural than you may think and is the result of the boat twisting and moving.  I would have a very careful look around the main high load areas - shroud attachments and join between foredeck and sidedeck particularly - as I think something is likely to be amiss somewhere else to allow the boat to move.  You may need to reglue and reinforce some other areas.  The carlings on the inner side of the side decks are much more structural than I had previously believed.  DON'T bodge it or you will have continuing problems.  It will be a tall order to be sailing again this weekend.


Posted: 13/05/2010 11:24:23
By: Andrew M
Try taking it to Phil 'Dirtyhands' Scott who is based near Hams Hall, just east of Birmingham.  Phil does lots of repair work on Merlins and knows what he is doing.  He can be raeched on 0797 3720732.


Posted: 13/05/2010 12:48:03
By: Midlander
Thanks for the advice guys - will try to give Phil a call tomorrow.

Andrew M - I can tell its not a quick job, and I'm too busy for the next few weeks to sail it anyway :) It's not that bad a crack, and it would be sailable in light winds. I do myself tend to err on the side of caution, but I'm not convinced about the boat twisting and cracking, as I can place the exact moment that it went "crack", when I sat on the side a little too far back, where I suspect it was a little weaker.

From then on every time I sat on it (although I tried to sit as far forward as possible, where there was the supporting cross beam underneath) it got a little worse, and as the split moved forward, the pressure from the jib cleat didn't help either and took over from the action of me sitting on it.

Thanks everyone.


Posted: 13/05/2010 21:07:41
By: Richard H
Hi There, 

We had exactly the same thing on 3239, also built by Rowsell Brothers just a few years after yours, and it repaired fine. We found that the glue was failing not only where you see it now, but also on the other joints between the light/dark wood so wherever possible we opened it up, cleaned it out and re-glued with epoxy and its absolutley fine now.

We sail over at Chelmarsh (not very far from you) with a similar sized Merlin fleet, so we'll have to get together for a race or two :) drop me an email sometime.


Posted: 13/05/2010 22:11:16
By: Robin Szemeti
Hi,
Paintcraft are not too far away in Nottingham and if you do not want to tackle it yourself, they will help. Ask for Nigel.


Posted: 13/05/2010 22:21:17
By: John Haynes
Same thing happened on 3233 (Rowsell NSM).  As KM has described, cleaned out and epoxied the splits/cracks, then placed 1/2 inch small knees (using deel wood) underneath to support the joint between the side deck and inwale to prevent it happening again.  That was four years ago and it hasn't.


Posted: 14/05/2010 13:56:10
By: Richard (3233)
Same here, I was only this afternoon cutting cardboard templates for some small knees ... will rout them out of 6mm ply and epoxy-fillet them into position ... about 2 per section so 6 or 7 knees per side in total.


Posted: 14/05/2010 16:39:34
By: Robin Szemeti
Just to say that after thought I still think the issue is that the boat is trying to twist in a breeze and waves downwind, plonking the helm down hard is the nail in the coffin that finally causes the carlin to give up.  I have had a fair bit of splitting in the carlins on Heaven Sent after vigorous sailing in 2008 at Salcombe then the Nationals, since Laurie beefed things up round the aft end of the foredeck and reglued everything not only have the splits not recurred but the boat is definitely stiffer and quicker.  The fix was to extend the block the jib cleat sits on around the corner joining foredeck to side deck - this is an obvious structural weakness that has been removed on more recent boats with a continuous curve linking the 2 structures.  Look carefully at the area under the side deck near the shroud and the bulkhead and see if there is any cracking.
If you ever get the chance to play with a deckless Merlin shell you get an idea of how important the decks are at stiffening the structure


Posted: 14/05/2010 17:57:05
By: Andrew M
This is very common, often due to impact damage or sheer old age (Or in some cases inpact damage due to old age!!). What kind of state are the rest of the decks in? In your photos the varnish is quite badly blown, which will have allowed water in. This would have frozen on cold days/nights over the winter and started to pop the joints. My point being the other side is most likely not far off going either if the deck is in similar condition.


Posted: 14/05/2010 21:12:54
By: Chris M
Chris - There is some general weakening of the varnish starting in some places on the deck, not too bad in these areas. When I spoke to Phil Scott he suggested doing something with the other side as it was likely to happen there too.

Robin - sounds good, although I suspect your venue will be better than ours, as I've had to replace the rudder blade on my Merlin as the 2 feet depth over about half the lake was a bit of a problem :) Interestingly, with little or no centreboard down it still goes well upwind!


Posted: 19/05/2010 18:34:40
By: Richard H
heh, sounds rather shallow .. hope you don't get a drought :)

I am seriously hoping ot have mine back on the water next weekend (ie in about 10 days time ... got on last little epoxy job to do ... and the final coat of two pack .. wold be done know of dew had not formed and given the last coat a matt finish :(

You are very welcome to come over to Chelmarsh, just let me know when and I'll be there to welcome you, they are a very friendly bunch, and it would be good to have another Merlin to play with.


Posted: 19/05/2010 20:44:33
By: Robin Szemeti

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