28 foot Crusier

[Scott Dunsworth]

I cant remember what or how the Belhaven plans specified the building of the dead wood. I believe I got it from Sam Devlin's book and ok'd it with Graham. In any case it made for a strong very stable way of doing it. As you know lamination's are much stronger and stable than the same size of dimensional lumber. That's the reason we all laminate the centerboards and plywood works out so well in so many applications.

[Scott Dunsworth]

Peter on your 28 did you ever consider making your main tabernacle from aluminum? Someone a while back asked Graham about using aluminum and if I remember correctly he was concerned the a aluminum tabernacle couldn't be sealed long term.

I just have this nagging thought about all the stress on such a short tabernacle. Mine main mast is 35 feet from the deck and will carry 320 feet of sail.

I have been messing around with some drawings on how to permanently seal it at the deck. Mainly a 45 degree edge routed around the the deck where the tabernacle inters the deck. There's more to it than that, but that's what I'm thinking. The groove would be then filled with 3M 4200, not 5200, so it could be refreshed when and if necessary. The mizzen is a non issue, it is 26 feet and will carry 132 feet of sail. The mizzen tabernacle is about 4 feet high above the deck and is also secured to the cabin.

I just keep thinking about being off shore for a few weeks at a time. I would just trust aluminum more.

The stress's on the main tabernacle would have to be very high on my build. Here we have a short tabernacle with a tall mast trying to raise 2000 lbs of lead ballast when the rail is close to the water.

On another subject, I know you did your research on dealing with lightning. All that I have read says to make as straight a path to the water as possible. There is no way for me to get the main protected by a straight path. The mizzen may be possible straight to a keel bolt, but the main would have a fairly long run to the first keel bolt after a 90 degree turn. Most marine surveyors recommend a 12 inch square copper plate on the bottom of the hull under the mast if a straight path cannot be done to an exposed keel. But that concerns me, would that dissipate the strike or simply blow a 12 inch square hole in my hull? I'm guessing nobody really knows, every strike is different in some way.

[PeterP]

Scott, my tabernacles don't penetrate any deck so sealing is not an issue. Strength is a different problem altogether. The mizzen has two wraps of 18oz glass, the main has 3. We'll see. Aluminum would be nice but I'd have to pay someone to make it and that eats up money real fast. Besides, a couple of years ago I went through a maritime museum in Holland and it was all wooden tabernacles. Pretty amazing scantlings. As for the lightning protection mine runs down mainmast through the anchor well to the foremost keel bolt. It is not a direct path but the wire sweeps a very easy arc - ^ 3 ft radius.PeterP

[Scott Dunsworth]

A short tabernacle with stays wouldn't bother me to much, but unstayed it does.

A three foot 90 sounds a lot better than a straight 90. With a straight 90 I would be afraid the release of energy would continue down and blow a hole.

Thanks for your input.

[austateaud]

Nice to know your each thoughts guys.

Cheers!

[Howard]

Scott:

Don't know how closely your tabernacles relate to the P26, but on those, the tabernacles extend all the way to the keel. Both attach to bulkheads, and on the main, there is 2X to 3X more tabernacle below the deck than above. Looking at it from a distance, the most leverage would seem to be on the lower mast section, with only a short piece of bury from the top of the pivot point to the deck. As explained to me, however, the leverage force does not end at the bottom of the mast, but extends all the way up and down the tabernacle.

Still, there is a substantial leverage force and on existing boats, it shows up on the center piece that lays flat to the bulkheads. One way to reinforce this section is with glass, but also to select a plain or flat sawn board for this piece, with grain running with the strain vs. across it as a quarter sawn board would (will split). As I see it, that leaves the bottom section of the mast as the weakest link. I can think of a couple ways to beef that up, if necessary.

As for lightning protection, I've researched it and studied the recommended solutions and after considerable head scratching, have yet to think of a design that would take a lighting strike down the mast, through the boat interior to ground somewhere in the water that I would trust to not do any damage.

[Scott Dunsworth]

The way I understand lightning, if there is not an straight path for the strike to exit, it will find it's own way. This includes guaranteed side flashes to the engine, wiring and all metal objects. Along with making it likely to blow through the hull below the water line somewhere.

The catch 22 here is a boat without protection is less likely to get hit than a protected boat. But the protected boat always receives much less damage, if any and the unprotected boat always receives much more damage. Including the possibility of becoming a small reef for marine life.

I have a lot of time before I have to decide on the main tabernacle, so I'll keep kicking that thing around.

I do know that the mizzen tabernacle cant go to the keel because the diesel will be in the way.

I understand the main tabernacle has a long leverage arm, but it also has a hard place right at the deck. This is what concerns me.

Lightning protection on the mizzen is a bit troubling also. The mizzen tube will stop right over the engine. If it doesn't have a real good path out I can see it jumping through the engine down the prop shaft and out. Possibly destroying everything along it's way including the shaft seal.

The flat sawed wood makes sense also, I had the same thoughts when I did my Belhaven. I also pasted it on to Kyle when she was building her tabernacles for her Belhaven last year.

[Scott Dunsworth]

I have decided to put another layer of light glass above the water line and a layer of 12oz. below the water line. I'm afraid the heavy 17 oz biaxle cloth is going to print through the finish of the top sides. I don't know how many of you know what print through is, but the heavy glass will eventually show the weave through the paint on a epoxy glassed hull. Our boat is going to be in the weather and sun the rest of it's life. I'm not going to paint her white or Yellow , probably the cream that the island packets use. So my hope is a thin layer of 6 oz plain weave will prevent this from happening. As for the bottom I'm not worried about print through, we all know how bottom paint is. I'm just doing it for extra abrasion resistance and hull strength on the bottom. This extra glass will only add about 84 pounds to the whole hull, that's only about 3 pounds per foot.

I do need to be careful not to add to many beef ups, but this one for the minimum weight gain I think is a good one.

I'll be able to cut some weight above the water line by using okoume ply on the inside of the decks and cabin foam core sandwich, but will use meranti on the outer layer. This will give me a more damage resistant deck than the okoume and help me stay within Grahams designed weight.

Graham did surprise me when he told me I would be glassing the decks and cabin exterior with around18 oz glass. I think I'll do a 12oz layer with a 6 oz layer over that for the print through issue. I'll lay them in a time frame where I'll have a chemical bond.

I glassed the deck and cabin of my Belhaven with 7 oz and if you look real close you can barely see some print through on the cabin sides. Surprisingly the hull was 10 oz glass and I have never seen any print through on it. That may be because of all the primer and paint on the hull sides, I don't know.

Just a bit of trivial, Graham didn't name this design the Candice 28, I did after my second late daughter. We lost her in 2000 to cancer when she was only 20. Candice will also be the the name of the boat when finished.

I hope the boat has the integrity and toughness to take all that is thrown at her like Candice did!

[Hirilonde]

I have decided to put another layer of light glass above the water line and a layer of 12oz. below the water line. I'm afraid the heavy 17 oz biaxle cloth is going to print through the finish of the top sides. I don't know how many of you know what print through is, but the heavy glass will eventually show the weave through the paint on a epoxy glassed hull. Our boat is going to be in the weather and sun the rest of it's life. I'm not going to paint her white or Yellow, probably the cream that the island packets use.

Print through is often the result of post laminate cure. It is more likely to happen with a dark hull and/or southern climes. It can't hurt to take precautions though.

[Travis Votaw]

I repaired PILGRIM's main tabernacle (at the hinge bolt) with 12 layers of glass tape and epoxy. The side pieces had begun to split apart from the back piece of the tabernacle due to the hinge bolt not being tightened enough to spread the mast load to the windward side of the tabernacle.

Since the repair, I have sailed her in strong winds several times and the repair is holding.

You can also bet that the hinge bolts on both main and mizzen are now tight .

[Howard]

Travis:

Sometime when it's convenient, can you take some photos of your mast tabernacle? I'd like to see where the problems were that you had to repair.

[Scott Dunsworth]

Well it's been a year now since I started this tub and shes still not turned over yet. I need to get my priorities in line.

[Scott Dunsworth]

I got the stern cut in today, here's a few pic's. Got some minor faring to do yet. Tomorrow we'll cut about 4 more keel lamination's, I'm afraid to go much further than about 8 inchs on the keel at this time.

[Scott Dunsworth]

I also did some testing with the cut offs of the stern tonight. The port side had on two joints with small voids in the glue joint. I could not break the pieces by standing on them against the glass. When turned over to the inside which hasn't been glassed yet, I could break the hull cut offs, but it never did break in any of the thick glue joints, it always split the wood instead, most of the time right down the center of the plank. This was a huge boost in my confidence in this method of building. By the time she's glassed inside she should be a very strong hull.

[wkisting]

Looking very nice Scott. I can't wait to see the interior start to come together. (I'm sure you can't either )

[Scott Dunsworth]

Finally I have got four days to work on my boat. So we will be doing some fairing of glass overlaps and install some more keel lamination's. Also going to start drilling keel bolts.

I was looking inside the hull the other night and it just looks so huge inside. It doesn't look like I could ever fill all that space with equipment and furniture! A 28 is a very big cruising boat for me but about 8 feet short of the average now days.

We did some measurements the other night also and it looks like instead of a normal v berth, we can get a full size mattress in along one side of the hull and still have standing headroom off to the side. The aft end of the forward cabin is 8 feet wide. It would be nice to have a regular mattress up there like some of the larger boats. We would have to sacrifice about 6" of main cabin to do it and make some wedge shaped lockers, but may be worth it. We also can build in some drawers under the bed.

 

Kyle that is doing a wonderful job of building a Belhaven is flying all the way from NV to help me sand and what ever is needed in June. Very unusual that someone likes to sand that much!

[ricknriver]

Good to see your build is underway again and looking good. Good thoughts on bunk/bed alternatives. Always thought most comfortable possible sleeping very important for enjoyable cruising.  I plan to have the BH at the Spring Messabout Chick and I are trying to conjure up at Lookout in April if you want to try another sailing break. Safe sanding. Rick

[Scott Dunsworth]

Been thinking, That's usually pretty dangerous for me  !

 

But anyway of trying to build a super light weight spindrift 11 as a dink for my 28 that could be hung on a davit. I know davits are ugly and it's pushing it to install one on a small 28. But I'm getting old and clumsy. We will have a walk out transom anyway and it just seems it would be so much easier to just step off the swim platform right into the dink.

What I'm contemplating is building the spindrift 11 with 3/16ths okoume. I would do the 10 but I built a 10 for my brother and he said he would do the 11 if had it to do over again. I'm not a big fan of okoume but it is light, only 8.8 pounds per sheet. I would skip glassing the hull but she would get banged around to much to do that. Probably some 4 oz plain weave glass inside and out, 10 oz tape for the joints, which would add about 8 pounds over a just epoxied hull. I would probably make a few thin laminated stringers to stiffen the bottom just a bit, or order some of those carbon fiber strips instead. No sail rig, so no centerboard trunk, board, rudder and bare minimum hardware. The new Jessy would be a better choice being designed for motoring, if it wasn't 12 feet long. The 11 will still hang over the beam by 7 inches on each side.

 

Would probably add just enough foam ( foam is heaver than air ) in the tanks to float her if she did come apart or was holed. Very thin laminated rub rails, laminated because you can get the same strength with less wood and weight. Then add a thin rubber bumper to the rails. One area I'm concerned about using the 3/16's is the seat tops. I could laminate some small seat stiffeners or use a few 1/8 inch okoume scraps I have for a few extra bulkheads in the seat tanks. I need to be careful here or I could end up with the same weight as using 1/4 inch for the seat tops.

The design of the regular spindrift I believe would be still plenty stiff using the 3/16ths, with the seat tanks running the length of the hull.

 

So minus the 2 hp outboard my goal is to come in around 60 pounds or less for a fully glassed hull.

I want the davit for solar panels also, there just really isn't a better place to put them. Hopefully with the weight of the davit, 200 watts of panels and my light spindrift, minus the outboard mounted to the dink I can come in at about 140 pounds or less hanging from the stern.

Having the davit I probably wouldn't tow her much but if I did the wind may blow her over being that lightweight and just laying on top of the water drawing only about 1/2 inch of water unloaded. I might tow her if I was just moving from one cove to another on flat water.

Anyone got any other ideas on how to cut the weight anymore?

 

Scott

[TrailerSailor]

Maybe you should build a 16ft Dinghi and a 50ft Sailboat???? But of course someone can overload every boat....;-))

[hokeyhydro]

3/16" ??? I think you mean 3mm Okoume. That comes in around 9 lbs a sheet. 3/16" is 5mm and hard to locate and around 20 lbs a sheet.

I don't think glass on both sides will save weight, and since the wood is thin it won't form a very strong composite structure. I'd stick with outside glass for ding resistance, forget seam on outside since you will glass it. Now if you want light, cedar strip. My 9' l. x 4' w. cedar strip dink weighed in at 50 lbs with 6 oz glass both sides and doubled on the bottom.