1970 Coronado 15 Hull # 553 Repair, advice welcome!

Hello,
I have appreciated this forum, especially the thread involving 5monkeys and canracer's repairs of this boat. I am now taking on my own repair of hull #553 which I recently took home.
It seems to be in decent shape. I have removed the forward bulkhead. The tabbing of fiberglass tape had 'unglued' from the hull.
I've included a few pictures from underneath. The foam is dry, the thin plywood on the underside of the floor is strong and dry,and the 'fin' of thin plywood going from centerboard trunk forward is a bit damp, but seems stable and strong still.

The existing compression post seemed inadequate, as it was just a 1*4 piece of plywood screwed into one side of the 'fin' below and butted against the underside of the mast step.
My current plan is to rebuild a stronger compression post, and I also want to add the secondary bulkheads mentioned on the C-15 tuning guide, which will be located under the chainplates.
I will add more pictures, and I am hoping for some encouragement and advice along the way!

Speaking of Chainplates, the wood backing plate is dry but I can break off small pieces from the edge, as though it is very old. I imagine it is still strong enough to keep the small metal backing plate from pulling through the fiberglass, as it is still able to distribute force just fine. I will add the picture as soon as it gets approved to my gallery.


One more concern: the stiffening material which is built onto the inside bottom of the hull seems waterlogged. What is this material? Will it still provide stiffening if it is intact but waterlogged? If not, can it be replaced, or can I add stringers to the hull to make up for the soaked foam?
Thank you in advance for any information or advice! I am still referring to the aforementioned thread, and exploring the dark insides of the boat.
I removed one of the foam blocks today, and could remove the other. Is it okay to cut them in half to manage them better, will that make a difference? I believe I will be able to get inside the foredeck to affect some of these repairs.

 

Here is the boat over all,
and here is the chainplate backing plate I mentioned. The wood is cohesive but aged, and I imagine it is plenty strong to distribute the forces onto the fiberglass on a wide area.

 

Any waterlogged wood is useless.
The stuff under the mast support and running forward on the keel line is plywood.
You should replace it.
Chain plates are fairly important, if the edges of the backing plate are crumbling, the whole thing is damaged and needs to be replaced. Seriously. The backing plates you show are really not good enough to spread the shroud load, that is why the secondary bulkheads are recommended and standard in the later boats.

Cutting the loose foam in half won't matter a bit - it serves no purpose but to keep the boat afloat if it is completely swamped. Actually mine had additional foam inserted in the sides, under the seating deck. I have no idea if it was a good idea or just excessive caution, but the foam under the floor is not very much.

Good luck.

Marc

 

The deck & frames below look shot. You're probably going to have to:

1. Cut the deck off.
2. Measure new deck plate & framing wood.
3. Remove old decking & framing.
4. Replace with fresh material & bond with West 404 or equivalent structural filler. I recommend a layer or two of fiberglass around the wood and a very nice bead of West 404 around all structural connections to deck, hull and mated parts. If you do a good job and keep the boat drained and covered after use it will minimize saturation and the new parts will last for many years.
5. Re-install the deck plate (requires splicing the fiberglass joints with several layers of glass).

These are just high level steps. The devil is always in the details. West has a lot of great resources on their web site including the one below.

https://www.westsystem.com/wp-content/uploads/Fiberglass-Manual-2015.pdf

May the force be with you.

 

That is really hardcore. To make a good joint where you cut thru the sides of the hull, you need cloth on the inside and outside.
You can't reach the inside for at least 1/2 of the length of the boat. And including the transom.

Take a look at the pictures in the other C15 threads.
This is a small boat, you are not getting inside like a 25'er.

 

The tight space is one reason I suggested removal of the deck. The other is the wood under the deck is in bad shape. Quite a bit of work wrapped up in this project. Some skilled hands with a fiber saw & fiberglass repair + splice skills are needed. When re-installing the deck you might consider fabricating a lap joint that is:

a) Attached to the hull and overlapping the seam.
b) Can be pulled closed with temporary blind fasteners (e.g. Cleco clamps). That's about the only way to close up an enclosed area like that.

e.g. Closing up a blind area with cleco clamps & pliers. Tip: Wax the cleco tips so they do not bond to the epoxy.

​

 

Thank you all for the replies and information!
JosephT, how certain would it be that the wood under the decks is shot? It is dry and seems solid. It appears to have been coated with some clear sealant that is now peeling. There isn't any noticeable flex in the deck. The wood running fore and aft on either side of the centerboard trunk is thin plywood, but again, dry.

One of my short to mid-term goals is to learn basic fiberglass repair skills. Some of the steps mentioned seem high-level technical, but I am a quick learner and will be fastidious.
I'm aware that boat repair and boats in general are expensive and time consuming. I suppose that is why I purchased this smaller sailboat to make my mistakes on, and learn with, instead of being like my one friend who bought a 32' Ericcson and within a year it was sitting on the bottom of the lake!
Thank you all for the encouragement. I will post a further update when I get the new compression post figured out, and as I start the process of cutting out new bulkheads.

 

If the deck wood is in good shape that's good news. It looked a bit warped to me, but maybe it's just the perspective. Replacing the bad wood still looks like it's going to be very difficult to get in that tight spot under the deck...anything beyond arms reach will be tough. You might consider an access panel about mid-way between the mast & bow. Then again, my initial suggestion to remove the deck can still be done. It appears one other person did it. This is a Cononado 15.

​

Ref: New Member rebuilds a Coronado 15 https://www.boatdesign.net/threads/new-member-rebuilds-a-coronado-15.28959/

 

Hello coronadoVT, I'm sorry I didn't notice your thread earlier. If you still have the boat and are interested in making a few repairs, just let me know. That boat in the picture above is mine. I made that repair and many others.

 

Canracer,
Hello! Thanks for noticing my thread! I did get a little discouraged over the project, although after removing the bulkhead, I have had some promising progress in that
1. I found that I am able to squeeze myself into the compartment so that I can work in there without removing the deck. I do this by backing in from the cockpit, and from a kneeling position, I feel like I could do the necessary work to reinstall the bulkhead and reinforce the shrouds/chainplates.
2. I have taken the boat into my pond and rowed/trolled around a bit, which was fun and gave me new inspiration to the project, as I can see this is a very cool boat, very stable, and it floats, doesn't take on water, and looks nice on the water!
3. What is holding me back is a complete lack of fiberglass skills. I am considering buying some 4 inch fiberglass rolls and some epoxy mix, and trying to glass in some supports under the shrouds. I can access the location from inside the forward hatch, and from the access hatches on the sides of the cockpit.
How technical is this fiberglass work? Could I just cut some pieces of plywood to fit and glass them around the edges to the bottom/sides/tops of the inner compartment, under the shrouds?
Thank you for your time. I will make time to reread your thread on here, which has been helpful already.
I will also add some pictures!
Eric

 

Those are good pictures. The backing plate for the side stay looks old but as long as it's dry and solid, it could be plenty strong. I see a crack in the forward end but I'm not convinced that this could lead to a failure. What's the condition of the block? Does it have dry rot? Get a closer look and poke at it with a screw driver. If it's soft or soggy then you can replace it easily enough.

The main problem with your boat is the compression post for the mast. That hull should have never left the factory. Now's the chance to build it right.

What is the overall condition of the hull? Any other issues?

 

This image shows a new compression post. It's sits on a heavy bed of new fiberglass and between new stringers. Additional strength is provided by the bulkhead installed in the bow. I installed the bulkhead first but would have done it differently if I knew then, what I know now.

 

My original thread was messed up when photobucket asked for 500 hundred dollars to host my images. I tried to include, as much as possible, that original content in this thread. It's a good resource.
Coronado15 Rebuild https://www.boatdesign.net/threads/coronado15-rebuild.54844/

 

How is everything going coronadoVT?

 

Hi Canracer,
Thanks for checking in! I have to admit I have been discouraged lately on this project, but now that work is winding down, I am looking at it with renewed vigor.
I want to learn to do basic fiberglass repair, and this is a good starter project. What I need to do, is reinforce the chainplates ( I am thinking of glassing in an attatchment point below each chainplate, and using a turnbuckle and wire to strengthen the chainplate from below), and glass the bulkhead back in. That's pretty much all except for replacing the lines and making a new mast partner.
Would you think that 4 inch fiberglass tape would work to reinstall the bulkhead into the hull? I have no fiberglass experience at all, but I am eager to learn.
I will be ordering some fiberglass tape, 4 or 6 inch, and the resin/hardener, to start this in earnest this fall.
ALSO, I am happy to say that, through a combination of determination and flexibility, I am able to crawl backwards into the forward space of the hull, which will allow me to work on this without removing the deck.