Cockpit Coaming Rebuild

[John Stone]

When I rebuilt the Far Reach in 2009-2015 I installed new African Mahogany coamings. I bedded them with 3M 4000. I used teak colored polysulfide to bed the wood winch pads. This past season in the Caribbean water began to get under the coamings where the 4000UV failed. 3M 4000UV failure has been widely reported in the marine industry. 3M has only said they have since reformulated it.

After we returned from the Virgin Islands we hauled the boat out in August. I wanted to wait for the temperature to cool before starting boat work. In order to rebed them however I had to remove them first.

The first step was was to remove all the fasteners from the coamings. Not difficult because I can remove the overhead panels above the quarter berth to access the most hard to reach fasteners. I used a fostner bit to drill the wood plugs out. Gayle and I worked together to remove the 1/4-20 machine screws. Next, I used an oscillating tool to cut the bedding compound between the coaming and the fiberglass. I could not get to the bedding in the areas around the winch blocks. With as much of the bedding compound cut as I could manage I began to drive wooden wedges between the coaming and the vertical fiberglass face the coamings are bolted to. I knew there was a high probability the wood could be damaged removing the coamings which in fact occurred. The damage is not terrible but is extensive in a few places. 3M 4000 is not near as tenacious as 5200 but it is still a very powerful adhesive. I'll know more when I strip the varnish from the coamings at home. If I have to rebuild them it is not a very difficult project. I'll know more later in the week. Today, I cleaned off some of the bedding compound from the fiberglass.

Lesson learned: I will not use a polyurethane adhesive when I rebed them. I will probably use a single strip of butyl rubber. I might use polysulfide though for the winch blocks as it released with out a big struggle. The other option is Dolfinite, which I use for wood I want to be able to disassemble such as dorade box tops, kranze iron, bowsprit anchor rollers, etc.

Next step is finish cleaning the fiberglass of residual bedding compound and then strip the coamings back to bare wood.

[JD-MDR]

Thanks John. I'll be following. Refinishing the combings is one of my priorities, including the cap if I can figure out a way to keep the Spartan cleats. I can't find the link you posted on building yours. I might do it in Mexico. I'm thinking of going all the way up to Puerta Penasco to haul out . I guess I should bring all the bronze fasteners etc. with me. I would like to bring my old Volvo down to La Paz. I bet I could sell it easy down there or at least give it to a worthy person.

[John Stone]

Good to hear from you JD. Here is the link. Scroll down about half way.

http://www.farreachvoyages.com/blank-26/

I think to make the Spartan cleats work with a cap-rail you'd have to make an extension bracket. They are nice cleats but in my opinion not more advantageous than the bare teak cap-rails. I still have mine and though I don't miss them at all I might find a way to use them some place else.

[Jim Walsh]

I presume my cockpit coamings were bedded at the factory but it must have failed at some point in the past. Since I would never entertain the thought of removing them, as you have, I put a small bead of teak colored Life Caulk where they join against the side decks. It lasts for about three seasons but it’s simple to remove and renew.
It’s interesting to see a proper removal and rebedding process documented. It helps to reaffirm my decision not to undertake the task Good luck.

[John Stone]

I presume my cockpit coamings were bedded at the factory but it must have failed at some point in the past. Since I would never entertain the thought of removing them, as you have, I put a small bead of teak colored Life Caulk where they join against the side decks. It lasts for about three seasons but it’s simple to remove and renew.
It’s interesting to see a proper removal and rebedding process documented. It helps to reaffirm my decision not to undertake the task Good luck.

LOL. I hear ya. I was not looking forward to this project but in reality it looks worse than it is. As a result of the rebuild and many mods my skills improved dramatically. At this point the only difficulty is the drive to and from the boatyard. It's awful. A major PITA. I miss my boat shed and having the boat in my yard where I can work on it for five minutes or five hours. This is where having a boat on a trailer you can bring home at the end of the season wins every time. I'd love to work on the boat and take on all kinds of nifty projects if it was back in my shed. I've even though of building a HOA approved garage large enough to accommodate the boat and my shop. But it's too much money. If we lived out in the country I would do without hesitation. Alas....

[wikakaru]

I was expecting from your description to see the coamings split into multiple pieces. In the photo they look good. Is the damage on the other side?

Good luck with the project!

Smooth sailing,

Jim

[John Stone]

I was expecting from your description to see the coamings split into multiple pieces. In the photo they look good. Is the damage on the other side?

Good luck with the project!

Smooth sailing,

Jim

Some sections of wood peeled from the plank held to the fiberglass by the 3M 4000. I'll post some more pics when I have cleaned it up. I'm not really concerned if I decide to make new ones--not difficult or particularly expensive. Two 10' long by 10" wide by 1" think unmilled A. Mahogany is about $150.

But once I strip the varnish and bedding compound I will be able to examine them much more closely. If I can fair in the damaged areas with thickened epoxy or even grave in some pieces and since it will be unseen faced against the fiberglass I may do that.

MTF.

[wikakaru]

Some sections of wood peeled from the plank held to the fiberglass by the 3M 4000. I'll post some more pics when I have cleaned it up. I'm not really concerned if I decide to make new ones--not difficult or particularly expensive. Two 10' long by 10" wide by 1" think unmilled A. Mahogany is about $150.

But once I strip the varnish and bedding compound I will be able to examine them much more closely. If I can fair in the damaged areas with thickened epoxy or even grave in some pieces and since it will be unseen faced against the fiberglass I may do that.

MTF.

Whoa, that side is way worse than the first photos you posted. If you are lucky all the damage will be hidden and can be filled and forgotten, though I can also see why you might want to replace them.

Smooth sailing,

Jim

[John Stone]

Jim
Yep, they are banged up in a few places. No doubt about that. However, much of it is just varnish pulled off and looks worse than it is. Because the plank is bolted to the fiberglass coaming recess and because all that is hidden it may be inconsequential--non-structural in other words. In fact I could probably recess that whole four inch wide x 9.5' long strip and laminate in a corresponding piece of manufactured fiberglass and it would not make a bit of difference and be totally invisible. But, I would just build new ones before I went down that path.

I have some ideas on how to modify these coamings or new ones to make them easier to varnish and maintain.

I like the teak winch pads. I think they add a great deal of strength to the coamings since they, and the winches on top of them, are through-bolted flat to the deck and to the coaming--much stronger than bronze arched winch bases. But they are harder to maintain. I looked into bronze winch bases during the rebuild and they were quite expensive, especially for the big #46 Lewmars. So I'll stay with the teak ones. The biggest problem with winch pads is they trap water on the high side when sailing on the wind off-shore (water can pass under the bronze bases). With teak pads, deck water can't flow back along the coaming and escape. It's corralled between the winch pads and can sit there for days. I might be able to create drain holes to the cockpit--a whole new set of issues. So I'm thinking about that as well.

The bronze plates I installed on the top of the primary winch pad, between the winch and the pad, helped a lot with varnish maintenance. It's eliminated the horizontal varnished surface and did a lot to reduced UV damage not to mention negated having to varnish around the winch itself. I'll add those plates to the top of the secondary winch pads.

I also have a plan to eliminate the need to varnish in the tight space between the cabin side and the coaming caused by the "return block."

Anyway, it's an interesting and kinda fun project.

And lastly, I have been thinking about a way to install the coamings so I can remove them without so much invasive surgery. I have a plan and will share it if I determine it's practicable.

[John Stone]

After a dark and wet winter we have had some warm sunny weather. I was a slug this winter. I somehow got double pneumonia and didn't even know it till Jan. I was so tired. I did not want to do anything. But that's all behind me. Anyway, now all I can think about is sailing.

I bought some African Mahogany and jointed one edge, ripped the other side so it would fit through my planer, then took it down to 7/8" thick. I removed the teak caps on the old coamings.

Will use the old coaming to draw the layout for the new ones. Plan to make them an inch taller on the aft end.

I'm also making the teak stays'l winch blocks taller and will cap them with a bronze plate same as the primary winches.

I'm so happy to be back at it.

We have a long planned overland trip in our Jeep planned for March. I was looking forward to it all winter. But now I hear the sirens calling from over the horizon....

[John Stone]

Another photo.

[John Stone]

Using the old coamings as patterns I traced them out on the newly milled planks. I drew the lines to raise the aft end of the coamings an inch. Then, with a long guide bar clamped in place I cut the tapered top line with a circle saw. A let both end run a wild for now.

[John Stone]

I took the coamings to the boat and test fit them. I had to file one notch back about 1/16" and the coaming dropped right into place. Then I camped some 2x4s as wedges (cut the ends 10°) and wedged them in with some light taps with a dead-blow. The new stays'l winch pads fit well. I'd like to lower them about 1/4" to make varnishing easier.

The coamings will be topped with the bare teak cap-rails as before. The aft end of the coamings need to be shaped with the S curve profile. I may try extending the cap rail for them but will have to see what will work.

The hard part comes next--the return blocks on the forward end. There are some tricky compound cuts required on the blocks and for the angled half-laps. Thankfully, I documented the building of the coamings during the 2009-2015 rebuild, so I can go back and read up how I made them before.

The sooner I can get one or two coats of varnish on the coamings the better protected they will be from dirt and grime through excessive handling.

[John Stone]

Yesterday, I worked on the return blocks. I milled some 8/4 mahogany left over from the 2009-2015 rebuild. I planed a small section to 1.75" and ripped them a little wider than I thought necessary. Then, cut the dados. Next, I cut the 15° bevels to match the angles on the forward edge of the coamings.

I also cut off the old return blocks and dado'ed them to fit the coamings so I can use them as a mock-up.

Cutting the final inside bevel is tricky and potentially dangerous depending how I do it. Originally, I cut the outside edge last having left it wild so it was safer. Then cut the dado. I have a friend with a tapering jig and it might could work. I can also bandsaw them and clean the surface up with a bench-top sander. I won't cut them on a chop saw--too dangerous.

MTF

[Jim Walsh]

Nice job. If I tried to replicate this project the forestry police would arrest me for mis-treating wood products and confiscate my carpentry tools.