Buccaneer 24 Builders Forum

Cases need two strong points

Gday

If you are thinking of making a glass case a few points to consider.

You only have to make the top and the bottom of the case tough and strong. The rest can be a waterproof sleeve. I like to get strands of unidirectional glass and lead it from the back of the case and fan it up forwards and outwards. This caters for grounding. Underneath this should be about 4 layers of 600gm DB on a nice 20mm diameter epoxy glue cove. Get onto the inside of the case and add two layers of 440gm DB. (Do the whole thing in 440 if you like)

As to the sleeve itself. If you don't want the board to rattle only make it slightly larger than the board. So you start with the board and put a piece of thin carpet around it, then some plastic taped down. Then I would go with a couple of layers of 4oz plain weave and then two layers of 600gm biax or DB. If you would like to stiffen the sides a bit glue four pieces of 40x12mm cedar or similar on the side of the case and then put the final layer of 600gm over. You need the fine weave for water proofness. Without filler the larger spaces in 600gm can make a weep hole.

If the top of the case is the same distance from the bottom as the bottom to the CLR of the board you will need the same laminate. If it is more distance then you will need less.

cheers

Phil

 

trunk

CS covered the layup pretty well, but I will add my "quick and dirty" ideas I don't know what your skins are in your hull, but assuming the hull is cored in the board area, I would grind out the inner layer and foam about 6" to each side and behind the trunk. However you decide to construct the trunk its self, the joint to the hull and reinforcing around it is more important than the actual trunk. As CS has pointed out, the trunk is only loaded at the top-the hull skin takes the bottom stress. I would start with a 8-12 oz cloth inner layer for a smooth finish, make a nice 2" radius fillet around the hull-trunk bottom of well reinforced putty, use 3-4 layers of 20oz roving to "tab" the trunk to the hull and make the ends 6-8 layers of roving. The rear bottom joint area should be 3/8- 1/2" thick finished and the forward top almost as much where it attaches to the bulkhead. The sides of the trunk can be thin- maybe 2-3 layers of roving. The top edge can be stiffened with wood or foam or any other combination. The water comes up about 16" in the trunk, wood or other core can be used above the waterline. Finish the outside to your taste. I and many other people in the "field" tend to over build repairs, in this case, I think it is justified- adding 10lbs extra structure here seems well worth the weight. I am assuming hand lay-up and epoxy, vinalester poly could be used, but I trust the bond strength of epoxy and I really would not want to be face down in the bilge with the poly fumes in the summer Have a nice 4th B

 

Mine's lighter.... I suggested 3/8 ply because it would be stronger if anyone left out the top "seat". Building up glass at the hull trunk joint is a good way to go, the bed logs serve to hold the slot size while installing. A temp plastic wrapped spacer inside the trunk would hold the slot size while tabbing if that approach was used. That fiberglass stuff is 96 lbs per cubic foot versus about 36 lbs for the ply.

 

trunk weight

I just built a couple of smaller trunks (for my floats) of half glassed 1/4" ply and half all glass. From those, I would estimate the trunk as I described would be 22-25lbs installed. I would expect to use a little over a gallon of resin. I know a wooden trunk might be a little lighter, but the idea was to get rid of wood below the water line- this is a fiberglass boat. A trunk not braced at the top will fail or crack the hull- keep the braces to the seats in place. The Buc is deceptively light, but the sailing forces are very high and Crowther designed it as a unit- and EVERY part is important. B

 

"The Buc is deceptively light, but the sailing forces are very high and Crowther designed it as a unit- and EVERY part is important. B."

Thats why it is so important that the top of the trunk is stoutly supported athwartships, passing the wracking forces into the side stringers and thus the hull skin.

 

I'm not arguing bracing the top, I agree. I did see one tri (Walter Greene I think) where it had drop in braces that could be removed at anchor for interior room, neat until you forget! Any thing that helps give you a moment is good. Done well wood is fine above and below the waterline and the skills to use it are readily known by most people. Basic glassing isn't hard but it can be taken all the way to resin infusion, vacuum bagging and autoclaves, for a trailer sailer wanting to get on the water fast it can be hard to know where to start.

 

IMO you guys are building overstrong and 25 lbs for a board case seems excessive to me ... but then I'm a lightness freak. However, as mentioned, the mid side sections just have to keep the water out; I'd say 3 layers 6oz cloth plus paint would do that job fine - but bottom needs 5 layers carbon over heavy glue coving and top needs brace reinforcing - that's why I use carbon, stiff, strong, sets quickly (black) to steel hard and light - and because you're talking of a not large reinforced area, not expensive either.

 

Carbon is great in the right spots. He'll probably mix a quart of bog, lather on some glass tape and go sailing...

 

trunk weight and mistakes

On my two float trunks, one came in at about 15lbs and one at 17lbs installed. They are 12"x30"x1.25" on the inside. I intended to have about 1.5" thick but some how they shrunk Since they are in wood floats, I didn't have to do much heavy tabbing/reinforcing, and they shouldn't have as much strain as the main dagger. One hull had some voids in the ply so I added a ply/glass layer in that hull- so the 2lbs extra. I didn't use any roving or carbon, we will see if they are strong enough, I think they are. My foam board blanks are supposed to arrive tomorrow! B

 

new pic

From last weekend, before a race.

 

foam core help

OK! I have my foam board cores, but I think I need some help with board construction. I have only built up boards from wood and foam blocks, so they were stiff and stayed straight while I applied glass. My new foam cores are perfect foil shapes, but they are too bendy to hold their form- what do I do? Any experienced suggestions would really be helpful, I don't want to mess these up. I have two boards and a rudder to build. B

 

I'd lay up uni directional carbon I beams, (5 layers) cut the foam and lay the I beam through the thickest section - then with your foam glue attached front and rear and cured ... there's your straight foil for laminating on. Just imo of course.

 

Thats a good one Gary.
But Bruce, if you don't need a rigid spar in the centre lay wax paper in the concave sections of the foam block, lay the foam core in, then stand the whole lot on a firm flat surface, (ie:kitchen counter) and lay up the first coats of F/G one side at a time.

 

New builder

So far i've spent the past few days reading
The bucc 24 thread, the 22-24 tri thread, the bucc vs kt24 and a few others along with this one on page 45 of 60 so far but i thought i'll post and introduce myself.
I ordered my plans from OS7 a few days ago (many thanks)
So far my plan is to spend july looking at the plans and figuring everything out including what mods i want to make so far I think i'm going to do the suggested stretching to make it a 28. Using the wooden beams (capricorns i think too late to remember).
Perforated plywood instead of netting between wings like OS7
I plan on making it a liveaboard so cabin space is going to be highly important so i am seriously leaning towards in ama foils, like ...the yellow bucc.
I am an amateur sailor have been a carpenter before
Plan on building a sailing dinghy to use as a future tender and get some more experience sailing. Thinking it's going to be alot cheaper sourcing a used mast from craigslist.
I'm 6'3 beginning to ramble so to end my intro
what do you think of a shadow free area to put a solar panel and possibly small wind generators in the ama's
and does this have anyplace on my boat
http://www.homedepot.com/buy/lumber...ure-resistant-plywood-underlayment-63705.html

 

I think first you should look at the b28 thread ! if that is what you really want.

If you want a live a board then I think you have the wrong boat, I would look at a cat for better load carrying.

I think 24 to 28 is a bridge too far 26 sure !

Wind generators on the floats is not a goer in a boat this size.