Bulkhead Replacement Questions for a Cabo Rico 34

Greetings! I recently purchased a neglected Cabo Rico 34 displacing 18K Lbs, which required gutting of bulkheads and cabinets due to water damage. What would be the two best options for new BH material for a boat such as this? Original BH's were 3/4" teak veneered marine plywood, installed as a single piece for each install, but also looking at at reducing risk of future rot, and perhaps improving strength (not that that was ever a problem for the CR's). For the rebuild however, I believe the larger BH's (main and forward cabin, which are both glued to aft and fore wall of the molded head/shower insert, and therefore those walls enclosing the head will need to be cut out with the bulkhead) will need to be installed in sections due to space constraints (which that did not exist when the boat was being constructed), and then glassed together due to their size. Also figuring that after cutting away the fore and aft walls of the head/shower insert, the new bulkheads can have a couple layers of glass applied to the backside walls (enclosing head/shower) and and then faired back into that insert. Also planning to use +/- 45-degree biaxial tape for the tabbing. Any knowledgeable guidance on materials, tabbing (including number of layers of tabbing), and overall approach to this job would be appreciated. Boat is mostly gutted at this point, with a couple more BH's to remove, and existing tabbing ground out. Then the reconstruction can begin.

Thanks in advance!

 

Welcome to the Forum JK.

It sounds like you have a major re-build on your hands here - are you going to gut her totally, or will you be able to still leave some bits inside?
If you have some photos of her, inside and out, please do post them - everybody on here loves photos of re-fit work.
And this thread could develop into a Blog showing the progress of your re-fit.

Re new bulkheads, you could make them out of marine plywood, or you could make up foam (or Nida-core) sandwich fibreglass panels and use these instead. Or even make up very fancy vacuum bagged panels, but that is really only worth it if weight is critical, and it sounds like you have lots of buoyancy available at your disposal.

 

Thanks for the feedback - hadn't considered foam bulkheads. Yes, it is a major project, but I knew that going in, and have done a major refit before with an Ericson 29. I think there are a few panels I can save - and will help stabilize the cabin top as all other bulkheads are removed. These are the doorway openings to the head, v-berth, and aft cabin, which have some ply, but also lots of solid wood which did not rot. Also some above-settee/galley minor BH's that were not immersed will stay. For some reason, the ply in the doorway panels that were immersed don't seem rotted with the 'probe' test (basically pushing a pick into the wood to see how soft it is), but all the primary athwartship/structural BH's rotted significantly and must be replaced. Not sure how structural the doorway openings are, but certainly provide some rigidity to the boat. Most of the boat will be gutted, and have already completed the better part of it - plumbing, electrical, mechanical, appliances, etc. I will upload some photos when I have time to pull them together (along with video I've made - yes, thinking about the vlog/blog), along with a build schematic. I feel confident doing this, and have some in-depth experience with all of this. Some big decisions to make, and before I spend the $$ wanted to vet it with the experts. Thanks again!!

 

Excellent!
That is the most important thing, having a pretty good idea re what you are letting yourself in for - so many folk approach re-fits very naively, and get discouraged quickly when they find it will take twice as long and cost three times what they initially estimated.
Please do post some photos (and even a video, wow) when you have time, and you can be sure to get a most enthusiastic response on here.

 

You are doing such a job as I am, Complete refit of a Alberg 30. I don't have all the knowledge in the world but here is what I did. I used marine Ply 3/4" for my bulkheads, I dado-ed out of the hull side of the bulkhead panel 3" a 1/4 recess into the bulkhead.
So that as I laid layers of fiberglass it would slowly build up to just over flush with the bulkhead when fiberglass tabbing was complete. This turned out to be about 7 layers of bi-axial cloth. If you don't do this you will end up with a very thick edge of fiberglass over the bulkhead plywood. My last layer of fiberglass I put on went over the 3" daddo to 4" up the bulkhead to tie it all in. I went a bit further and drilled holes and put fiberglass strand string to both sides and fiberglass them in.. Sure there is no need to do this but it made me feel better.


Before I did all this i coated the bottom of the bulkheads several times with slightly thinned epoxy to seal the edges before I installed them. I put 1/2 pieces of dowel slightly hot glue to the hull to keep the bulkhead off the hull put in thickened epoxy fillets in between the dowels in several locations let it dry and then knocked out the dowels leaving the gap ready to fill with epoxy fillets. don't think the gap had to be 1/2 but that is what I did. I used large Popsicle sticks from home depot to use as a fillet tool.

I totally overbuilt the bulkhead tabbing. One thing I cant over stress if you don't know is that really take the time to roll out the air bubbles before you finish each layer. Makes the following layers so much easier to do. Also if you haven't started to fiberglass the bulkhead yet, Makes it much easier if you have a rough surface on the hull, to take thickened epoxy like filler , I used milled fibers or fumed silica and lay a thin layer along side and over the area you are about to fillet and fiberglass and make yourself a smooth surface for your first layers of fiberglass. If you don't do this rolling out air bubbles over rough surface is not easy and leaves lots of bubbles you can't push out. I used bi-axial to start then bi-axial with mat, then bi-axial then bi-axial and mat and so on. I prefer using biax with mat for many things as its so easy to wet out prior to laying it down holds its shape better than whetted out bi-axial but bi-axial is cheaper than biax with mat.. (stitched mat ) this is important if using epoxy.
I like 1708 bi-axial with stitched mat for laying fiberglass over re cored balsa decks from the below side, makes it so easy to do.

The green stuff you see is Total fair that i used to coat the fiberglass and make a smooth surface over all the fiberglass. I am sure there is no real reason to do this either as paint will cover it to.. But I like everything to be smooth when I paint.

I know everyone says its not worth the money and you will never get your money back. But for me, not about someone else value, it's the freakin joy of building something, I am having so much fun doing this.. financially I planed for this for awhile, purchased stuff long before i started.

 

Wesley - Thank you for the detailed account of your bulkhead project! It looks like you are doing a fantastic job! Yes, the existing bulkheads on the Cabo Rico are dado'd as you describe, but the layers are only a few of a heavy 90-degree/0-degree cloth in polyester resin. The BH's weren't sealed, and water got into them. I was able to 'pop' some of the tabbing off not only the BH which I might expect in it's current state, but also where it is glued to the hull, which surprised me. I definitely plan to rough up all the surfaces that will receive glue, sealing all edges, maintaining the gap as you described, and using epoxy. I had planned on using +/- 45 deg biaxial as the tabbing. I like your approach of alternating with triax including mat, and had already considered drilling through and running glass strands as you have done as a final reinforcement for a bulletproof bulkhead. Don't know if I'll paint the inside of the hull as all that gets covered - any specific reason you're doing this?

What marine ply to did you use? Okoume, Meranti...? or something else? How did you come to the decision to use what you did? I'm considering using a teak veneered marine ply since that is what was used originally, as all BH's are exposed and integrate with the teak trim aesthetic. Had also considered Coosa, and then laminating a teak veneer over that.

As for the money, I think it is all relatively affordable, and not a huge expense when doing it yourself as we are doing. Hiring this stuff out is where it gets prohibitive, and a non-starter for me anyway. The boat was relatively cheap due to it's condition. I hope to sail this boat into retirement (still a ways off) and hand it off to my kids to take me sailing when I'm too old. So the effort and costs are worth it to me!

I'll share my work once I get it together. Thanks for sharing - and beautiful work!

 

I would build foam with rebates at the intersections to simplify fairing inside.. Create a wood frame backer and screw the panels to it while they are bonded on the seams. Then remove the backer and glass tape the seams with 1708 tapes.

if you have more questions, let me know, this method is also the easiest imo

 

Jkenan: I choose Merante 3/4 due to its considered stronger and it is an bulkhead that has supports for deck stepped mast beam. And I don't like dark areas and I am going to paint all in white other than wood varnished trim,
There is no reason to paint all the inside in white to be honest other than I am a bit of a obsessive about being able to clean and wipe things down to clean and also brightens up the darker areas in lockers as as well. I tend to go overboard when I restore things. You can probably see in my picture by the green fairing that there is a 6" merante over the base of the bulkhead. This is laid over the fiberglass 7 layer on both sides of each bulkhead That is three layers of fiberglass over that. To complete this obsessive project I will be fastening this together with SS thru bolts every 8" pinching the layers of fiberglass tabbing together in on big over done mechanical attachment. In reality the base of the bulkhead is not 3/4" its 1/1/2" and yes i know its over done.
I love this boat and have since my youth sailing with my father in the pacific. So like you i am doing this for the love of the boat and myself. Its unless lost due to some disaster the boat I will sail into my old age.
Even though I did the fiberglass strands to mechanically attach the bulkhead to the hull that was probably enough, I didn't need to the extra sandwich over all that. Also I am told that you can also just through bolt with SS fasteners and washers the fiberglass tabbing as well when cured. Part of the reason i did all this extra comes from a bit of fear of something failing.

I gutted this boat and only used two of the old bulkheads as two were in mint shape, no rot no decay.

I like your boat, I looked at one couple years ago and I loved it an considered it but for me a bit bigger than I wanted. In the end I chose this Alberg 30 cause of a few factors. Its wonderful ability to heave too. Its narrow beam, I am expecting to have to do a number of haul outs as I cruise on some long voyages, an smaller is cheaper for mooring an hauling out. I will miss though the roominess of my Southern Cross 31 which I lost in hurricane Sandy due to the boat next to me on the hard was improperly set up by the marina.
In the end its my success or failure that will show at the end. Not to mention it will be designed interior as I want it to be and laid out for my comfort at sea and in a blow. Alberg 30 is a great boat but its layout didn't suite me in long voyages. Also Alberg 30 is a great design but was in many respects workmanship was not exciting. People either love them or hate them.

 

jkenan, Fall guy has a idea if you saw it above, I have done what he has suggested but not with foam if that is what he is suggesting. I have done this before but the backer plate made from Merante and made it like the pieces you in my picture, and left it as a added support and fiberglassed it in .. because I didn't want to tear out an entire BH that had other things being supported by it. if there is not a terrible amount of rot and its limited to the first couple inches, would save you some time. Only problem I see is that wondering how you would get to the side of the BH were the liner is. If there is a way to get behind the liner or the liner to the BH off this would be the way to go..

 

So, with Covid came the layoff. With the layoff came a very anxious spring and summer supporting a family, looking for a job, not getting anywhere with it, and not getting anything done on the boat (couldn't justify the time or money). With the fall came some traction, and with winter came not one but two great job offers, so I am back in business with the Cabo Rico 34! Wild year to say the least. Revisiting this thread, I can say that I've decided to gut the entire interior except for large FRP inserts: galley, settees, and fore/aft berth inserts which also house water tanks. All bulkheads will be rebuilt anew. I will be able to save the teak door frames (which are quite thick and beautiful), doors, and lots of the cabinetry facings including their associated doors. So, lots of louvered doors, frames, and cabinet facings will be salvaged. The interior, I've decided, will be done in a Herreshoff style interior, with oak strips about 2-3" wide (and v-groove seams) lining bulkheads, headliner, and inside hull along berths, all painted white. I have a ton of white oak lumber (I live in the country with tons of hardwoods, and my neighbor has a sawmill). I've also decided to go with 1/2" Coosa Bluewater 26 panels for the bulkhead cores, cockpit floor (double laminated to 1") and will surface them with white oak 1/4" strips, laminated to the Coosa, to make up the original thickness of rotted 3/4" ply. I won't have to rabbet the Coosa, and will simply laminate the white oak on top of the Coosa up to the tabbing, then trim it out in teak trim. That, with teak doorways and cabinetry, will lend to a very bright and warm interior, I think. With the boat gutted, I have ground out all prior tabbing, and am close to having a blank slate. Like Wesley, I plan to paint everything white once new bulkheads with oak laminate are installed and galley/settee/berth inserts repair and prepped for paint. Then install rebuilt cabinetry and trim it out. Glad to be back at work, and back to work on this project!!

 

Welcome back JK!
It has been a rather roller coasting year for sure - congrats on the new job, and on being to get back into your big re-fit now.
Please do allow this to develop into a re-fit thread, with lots of photos along the way - I am sure that everybody on here will follow it most enthusiastically.