JEM Watercraft

I've got my Sabalo hull built to the point where I've just glassed in the final two hull panels. I'm working on the placement of the hull fittings so I can drill, fill, and drill the screw and rivet holes.

I have two questions on the boat at this point:

1. The seatwell I made seems to be tight at the corners (read, it doesn't fit between the side panels quite). and loose at the middle from the "sheer" at the top of the seatwell and upper hull panels. I have dry fit it, and I have to put an alarming amount of pressure outwards to push the seatwell side top edge within about 1/4-1/8" of the hull panel it should line up with. the current gap is about an inch in the center of each side between the panel tops. This makes me believe I probably made a bit of a mistake when I put the seatwell side panel edges on the outside of the ends of the front and back seatwell panels, instead of on the inside, thereby making it somewhat shorter in length overall and somewhat wider at the corners.

Should I just grind it down at the corners some and force the fit there, and then just use a lot of bent rods or temp framing inside to push the sidewalls out to where they need to go, despite the pressure that will be stored up in the build once it is tacked and filleted and glassed, or should I jigsaw those four corners open, and try to re-fillet the corners a little narrower, with more bow out on the sides naturally. That'd be hard considering the frame is now part of the hull, and wouldn't easily serve as a mold any longer.

Also, for padeyes and such, the notes recommend backing the hull with a second layer of plywood. The problem that brings up is that requires some very long rivets: 2 layers of 4mm ply, a layer or two of glass and the thickness of the hardware, plus some length for the rivet to expand on the end . What about backing the hull behind the padeye and other hardware locations with some lengths of 1/8 or 1/16" aluminum barstock, epoxied to the inside of the hull? It could be drilled through, eeasily enough, would distribute the load along more of the inside of the hull, and would serve to prevent a rivet from pulling into the wood or epoxy from the inside.

A.J.

can you post a picture?

What he said

Hope this works - took pic locations from Ayjays build log on the other site. Are they any help?

Hmmm.... looks like the seat well walls don't have enough curvature. You could trim a little in some areas and see if that helps. You might need to make a couple thin filler strips for the bigger gaps.

Yep, I posted anonymous, then figured what the heck and registered. Anyways, I believe I can force the panel sides outward enough to make it tackable. I just prefer to have less "pent up energy" in the hull, but it might actually make it stiffer once I glass it. I just don't want to warp other surfaces a little by bending this one so much. Yep, a filler strip might be required in the gap. No big deal there, I suppose.

You might consider cutting a slit in the middle of the side cockpit walls. That will relieve the pressure and let it conform easier. That will be easier to custom fit a thin "filler" strip.

How's this idea: I measure the length along the curvature of the sheer edge of the side panel top along the length is is supposed to attach to the seatwell. I then compare this to the top edge length of the sidewall seatwell, and know approximately how much longer that top edge needs to be to get identical curvature to the sheer edge of the side panels. (I then subtract some reasonable fraction of that distance so I don't overdo it.) I then cut a slit in the center of the sidewalls of the seatwell, and using some clamps and some battens, clamp the top with that separation required to get a more adequate bowing out of the sidewalls, and then fillet the created acute wedge shaped void. Once it sets, I sand it and glass it in on both sides, much like a butt splice, thus achieving a better conforming bow out of the side panels of the seatwell.

Sounds like about 3 days added to the build, but it'll help it go together easier later if I can pull it off properly.

that sounded like a really good plan.

More help, while I'm at it: My sabalo has a crooked nose!! the top panels must have moved a bit out of alignment at the bow when I tacked them in, and i just noticed it. The tip of the bow skews slightly to starboard, causing the first foot or so of the panel on that side to be just outside of vertical, while on the port side, the panel tips in.

I've already glassed the inside and done some filleting on the bow. I could cut the seams back openfor a few inches, and use some creative clamping and re-fill, trying to make it more true, or I could mix up some filling and fairing compound, and get a little medieval with a grinder. It's just skewed less than a CM, but enoguh where I can see it, and such asymmetry bugs the heck out of me.

I am thinking because I've filled and filleted all the seams and glassed the inside, cutting a few inches on the bow seams won't accomplish much, because the panels are going to want really badly to bend right back to where they currently are, i.e. the angle and orientation of the panels is fixed further down the hull already, and redoing just the tip of the bow might just move the asymmetry further back along the bow. It might be better to just fill and fair the one side on the outside, and then grind them symmetrical enough to be not noticeable?