*(&@)$ cockpit coamings

[JMetzner]

I launched As You Wish last summer without cockpit coamings, having blown out the first set tightening them down. During winter maintenance (yes, it's winter already up here) I thought I'd make another try, this time running the first layer nearly all the way to the back of the cockpit. Using the method described in the plans, this set isn't going together well either.

So, I'm thinkin' about a plan B. What other methods have folks used to fabricate these dang things?

I thought about making a vertical lamination, bending the pieces in place. I think I remember someone trying it and saying it was tough. There are tight radiuses at the forward end of the coamings, subtle angles and with wanting to go with full length coamings, the swoop of the deck fore to aft becomes an issue.

I thinking maybe some composite of foam, fiberglass & epoxy might be easier. I have a bunch of RAKA epoxy left, but don't know what kind of foam core to use with it. Any thoughts?

Thanks,

John M.

Fairbanks, AK.

[capt jake]

I used the lamination method you describe. It really wasn't bad at all. Once the side laminations were together I attached the forward pieces of the coaming on top of that. I made up the forward 'swoopy' pieces as described in the plans but I glued them all together with CA glue and faired them prior to installation; then installed them on top of the lamination.

The aft coaming that goaes transverse was also laminated, though it was a horizonatal lamination.

I sanded and pre-finished all pieces with epoxy prior to installation. Counter sunk and bunged teh screws. the forward 'swoopy' pieces were attached from inside teh cabin with screws.

[attachment over 4 years old deleted by admin]

[waynemunro]

I used the method pretty much as described in the plans as far as cutting the pieces, but assembled and sanded before attaching.

here is a picture of the bits sitting in place before being stuck to each other

I extended the coamings right to the bach, but the bottom layer was in two pieces, as I didn't have a long enough piece in this wood to do the whole lot, I had the extendion on the bottom layer overlapping with the layer above so it held together better.

I screwed it from the uderside where I could, from the top where I couldn't and dowel jointed into the cabing side. applied lots of epoxy and hoped for the best.

here they are sitting in place after joinging and sanding (so much easier when not attached) and before attachment:

and as you can see, glue got everywhere on the day I attached them. I used wooden plugs cut from the same boards to fill the screw holes.

and all things considered I think they came out ok:

Good luck with your coamings, I think this was probably the single item that took me the most time of anything on the boat.

[waynemunro]

whoops, looks like I have blown out the width of the thread with my large images, sorry about that.

[capt jake]

Wayne did pretty much the same as I did. Looks great Wayne!

[MikeStevenson]

Wayne: Looks good. Is it still comfortable to sit up on the deck to hike out?

[waynemunro]

Thanks Guys,

Yeah Mike, it still seems fairly comfortable, I was a little worried about that while building, but in reality have not noticed any discomfort at all in practice, and have been sitting out there at least half of the time that I have been sailing. I think there is enough room between the toe rail and the splash coaming extension to 'nestle', I have a theory that the splash coaming extension even provides a nice little edge to prevent the slide down into the cockpit, I'll experiment a little more next time I am out.. and since summer is rapidly arriving that won't be long now.

[Dave R1]

John, I think building them as Wayne did makes the most sense. I would probably start by masking the boat and then epoxy up layers rough shaped and fitted to the slope of the cabin bulkhead as Wayne did. Then I'd pull them off the boat for shaping, smoothing and finishing. Then I attach them through the side deck (if you can get there) and through the cabin bulkhead. At this point, with your boat otherwise finished, I'd consider bedding the coamings in marine caulk before screwing them down. That would keep the water out but it would also keep you from having to remove paint on the mating surfaces to get epoxy to stick.

I took a different tack and added ears to the cabin bulkhead when I was cutting it out. That and the low coaming along the inside edge of the side deck do a pretty good job of keeping the water out of the cockpit. The coaming isn't really noticable when you (I) sit on it either.

[JMetzner]

Thanks for the tips guys. The method Wayne detailed is basically what I'm trying to do. The first time around I had the full stack of layers built up (screwed together) and sanded smooth. I disassembled the stack, was installing them on the boat when I overtightened one of the screws and blew out a couple of layers along a grain line. Yaaaaarg!!!! Had to rip it all apart before the glue finished setting. I've been using Alaskan Yellow Cedar, maybe I need to switch to something less brittle. The idea with the CA glue for the temporary stack up of the layers is a good idea too.

Did you guys make individual tracings for each layer as you built the stack? That's the way I did it ther first go-round, but had trouble with the layers getting wider as they went up (pencil line thickness). For this last try I made a template for the first layer and used it to keep the width consistant for each layer. I had to extend the forward end a bit on each layer as they moved away from the cabin trunk. Still had trouble with consistant curves at the front of the coaming.

Thanks again,

John M.

[capt jake]

CA glue can be very permanent, if applied properly. It is fast and not forgiving at all so have everything in line the first time! I use 'Hot Stuff'. I have a bottle of the thin and medium body as well as a bottle of accelerator. Wonderful stuff!! I also have a bunch of replacement tips for the bottles as they always plug up. Do try to avoid the fumes when it is kicking off. Nasty stuff!!!!

I can see the problem you are describing with the pieces getting wider, though I just cut inside of the pencil line, glued and thehn sanded it all fair.

[Dave R1]

John, if you are going to screw the individual layers in place, you could use round head screws or better, pan head (because they are lower profile) with a flat washer. Counterbore for the heads and washer and by all means predrill for the screws. The cone shape of a flat head screw acts as a wedge and splits the wood. Won't happen with a screw that is flat on the bottom of the head.

I'm not convinced that the screws would add much in the way of strength as compared to properly glued laminations. I might use screws as temporary clamps until glue cures and then remove them prior to adding the next lamination.

[JMetzner]

Dave,

Yep, the screws were only there as temporary "clamps" although I haven't been removing them before the next layer. Too much of a hurry to wait for things to dry. Dunno why, there's only about 7 months before the water gets soft enough again to go sailing up here. I have been pre-drilling and countersinking the screws. I didn't think about the wedge action of a flat head screw, though.

The more I think about it, I believe most of the problem has been from the wood I've been using. This last try was with some very dry yellow cedar. I think I may try something else. I don't really care about the grain, since they won't be bright finished. Also, I might be a little too picky about the fit. I'm too used to building furniture, but this ain't a piano. :wink:

John M.

[Dave R1]

Is your water already too hard to sail on? Ours isn't yet but I wouldn't care to even get in it long enough to get the boat off the trailer. Brrr!!!!!

[waynemunro]

John,

my process for cutting out the layers did not involve any templates really, the bottom layer was marked by putting the wood down on the deck, and running the pencil round underneath against the seat back. I then marked another line a fixed thickness in from that, set the jigsaw to the right angle (can't remember what it was, 20 degrees? most of them seemed to be), and cut out the shape, remembering to cut from the right end so that the angle went the right way. The next layer was marked using the cut our piece from the bottom layer, and so on, and so on. I think this is the process as described in the video ?

seemed to work ok, when in doubt I cut a bit wider, easier to remove more than add it back on.. and the belt sander with 80grit seems to remove wood quite quickly.