floorboards to convert to berth in CS20

[wkisting]

Hi all,

I'm planning to make some floorboards in my CS20 that can be lifted into place to fill in the legwell spaces to create a sleeping berth forward of the mizzen mast. I know this will mean adding a cleat (support ledge) to the seat faces and sides of the CB case, but I'm anxious to keep the weight down on the actual floorboards.

I have a nice sheet of 1/4" Okoume left over, so I'm thinking I might make a frame out of 3/4" thick x 2" wide Douglass fir stringers, then epoxy the plywood over the top. Do you think that a panel made this way would yield sufficient strength to support 200 lbs.? The larger floorboard/berth panel would be 19" x 49.5"). I can't go thicker than 1" overall for the panel because that only leaves 1/2" of height on the CB stringer to glue-and-screw on the support lip.

I read somewhere that Graham made floorboards for Green Heron using 1/2" thick slats over 1/2" thick cross supports, all from Cypress and/or Southern Yellow Pine, I think. What have others used? Recommendations? Pictures?

[Peter HK]

What have others used?

Hi Wes

It's always interesting to try to get a very light, stiff and strong panel.

For a cockpit table on a larger boat a few years ago I used 3mm ply glued onto both sides of 25mm styrofoam (with wood trim around the edge) so it looked like a thick wooden table but weighed very little.

For my floorboards/bunk supports (CS17) I thought 9mm ply wood be stiff/strong enough (maybe with a few cleats underneath) but didn't have a piece big enough left over. As I was keen to launch and had a sheet of 12mm (half inch) ply, I used that thinking I might do something better in the future. As it is they are lighter that I thought they'd be and nice and solid underfoot so I think I'll leave them as is.

They did need a wood block under one corner to sit nicely on the floor as there's a bit of twist at that part of the hull.

Cheers

Peter HK

[PAR]

Seat mounted cleats will work, but I used aluminum angle mounted to the cedar slats instead. The first two images are from a really poor camera, but the idea should be apparent. These two show the slats in the "up" position, the last image shows the slats removed, but they normally stow directly on the bottom planks. This a CS-17 with a slightly modified interior and centerboard case arrangement. The area forward of the thwart can all be made one large sleeping space (by raising the slat panels). The modified centerboard eliminates the arm, for wide open tossing and turning while snoozing.

[Peter HK]

Pictures?

I took a few photos when I was at the boat this afternoon.

Here is the floorboard down

[attachment=1]

Notice the cut outs to fit around the centreboard pin cheeks and the centreboard downhaul block.

[attachment=2][attachment=3]

Here's a photo of the cleats on the case and seats.

[attachment=4]

Cheers

Peter HK

[Peter HK]

Trying again

[wkisting]

Well, this is lucky... I was envisioning something like a combination of the ideas you two posted above. If I use the ply, I'll have a lightweight berth panel that is painted white like Peter's, but I had considered trimming it with aluminum or stainless angle the way Par mounted his, since it would preclude having to sand through the existing paint to glue-and-screw wood cleat/ledges for supporting the panel.

Par - Where do your panels stow when not in use for the berth? (Do they fit as floorboards? Or does the extra width of the aluminum prevent them from stowing on the hull floor?) Also, any concerns about the aluminum scratching up the boat finish while being moved about? And, if you're willing to answer a third question: What are the dimensions of the lumber used? (I assume there are cross beams under the slats for support, but can't quite see in the pics).

Peter - Did you do anything to add traction to your panel? One reason I'm considering the floorboard/berthboard idea is because I would like to increase traction in the forward area, where a little water on the floor can make things very slippery at present.

Thanks so much for the help guys!

[PAR]

The cedar slats are milled to 3/4" thick and are about 2 1/4" wide (going from memory now). Under the slats are several athwart pieces of 1 1/2" wide, 3/8" plywood, on about 12" centers. These are screwed to the bottom of each slat. The slats are oiled only (tung). Yes, they rest on the bottom planking as floorboards. I used vertical grain cedar for appearance, dimensional stability, light weight and good traction. They are spaced with a 3/8" gap and all edges are fairly heavily radiused.

Since the deadrise in the forward cockpit area is substantial, the floor boards need to be wider when in the lowered position, then when used as a berthboard. This permitted the use of angle stock and the distance from the seat edge to centerboard case is smaller then the angled distance from seat box bottom to centerboard case. This is partly because I placed the seat box stringer on the outside of the box to provide a toe/hand hold, clean up the inside of the boxes and add an architectural detail. I to had to notch the forward floorboards for the centerboard pivot and mizzen step, but because of changes to the case and board tackle, I didn't have any tackle low, on the side of the case.

The big aft cockpit has the exact treatment, but it's attached with 6 big, but short screws. I went to a lot of trouble lining up the aft compartment slats with the forward units so they looked like they belonged there. These slats are naturally much longer and run the full length of the cockpit, which also doesn't have the aft bulkhead seating box. There is a removable seat (as shown), but the slats run under it to the transom.

[Rod Thompson]

I too used cedar.  Fence boards.  They are light, rot resistant and provide traction.  Like PAR I will oil them.  Used wooden cleats.  Have slim but firm air matresses that will compensate for the spaces between the slats of the sleeping platform.

[Rod Thompson]

Wanted to inlcude this.

[wkisting]

Thanks for the detailed replies and pics, all. This is exactly the help/inspiration I needed. Once I work a solution, I'll post pics of mine to show what I ended up doing.

By the way, I very much like the look of Par's and Rod's cedar floorboards, but since my boat deck is finished bright with mahogany trim and a mahogany thwart, adding bright-oiled cedar floorboards might look out of place, no? I'm having trouble imagining it.

Here's a pic showing my boat's color scheme (just starting to plane at 7 knots)...

[wkisting]

By the way, I modified the CB downhaul from what is shown in the picture. To clear space to drop in a berth expander panel, I removed the whole bungee cord arrangement on the side of the case. Now a single line runs from CB aft through a small block to an "autorelease Clamcleat" on the thwart. I've used one on the rudder and it seems to release at about 30 to 50 lbs of force (on its lowest setting), so I think it will make a nice way to hold the CB down also without sacrificing the kick-up function, though I have yet to test it (I'm still re-varnsihing the thwart after swapping out the hardware and filling old holes). If it works, it will greatly simplify things.

[Peter HK]

Peter - Did you do anything to add traction to your panel? One reason I'm considering the floorboard/berthboard idea is because I would like to increase traction in the forward area, where a little water on the floor can make things very slippery at present.

The white paint on the floorboard (and the whole cockpit) is a nonskid paint. I don't like "slippery when wet"

Cheers

Peter HK

[John Turpin]

I may be a little contrarian here, but I've never liked seeing cleats in the cockpit foot well.  Primarily, I don't like the aesthetics of them, but also, they tend to scratch/annoy sailors' legs.  When in use, they're handy, but for the rest of the time (99.9%), they're noticable and clutter up the look of a pretty cockpit.  I'm just not a fan.

In my old plastic boat, this is what I did.  I made a cockpit grate that had built in legs.  When I wanted to convert the cockpit for sleeping, I'd just extend the legs and my grate became a bench.  It actually worked quite well.  Details are here:

http://svbluepeter.com/tetra-mods2009.htm#grate

[wkisting]

John, I agree with you about the downsides of a cleat on the seat faces. That's what made me start contemplating another way to attach the berth panels, such as PAR's aluminum angle lip idea, which may or may not work for my boat. I've thought about legs also, so it's nice to see your setup. The more I think about this, the more I am thinking I will only end up making a single panel that drops in place in the larger half of the forward seating. I just want a space where my wife can stretch out to relax or nap during a long day's sail, or where I can sleep if I take the boat camp cruising solo (and when my little girl is old enough to start camping with me).

Although I was attracted to the idea of having the panels serve as floorboards also, I'm now changing my mind. One thing I love about our CS currently is that when the floor gets wet, we use a little scraper-style shower glass squeegee to pull the water in the bilge back toward the Anderson Bailer. Since there are no floorboards, it is quite easy to clean up the bilge and evacuate nearly all the water quite quickly. If we had floorboards, they would have to be lifted out of the way to do this. So maybe I'll build just one berth expander panel, with legs or an aluminum lip, and store it in the forward area (under the foredeck) when not in use.

[Scott Dufour]

I've been toying with this myself.  I installed mahogany floorboard this year, and I'm looking to modify them also to be raised to the seat height.  I'm not crazy about the centerboard uphaul/downhaul configuration, so I'm looking to change that, too.  PAR, do you have some details on the changes you made, and can my existing centerboard be modified toward something cleaner like you've got, or did it need to be designed in during the build stage?

With two kids usually stored forward of the thwart (and all thier stuff), the uphaul and downhaul lines are constantly getting fouled.  (I sail in a lot of shallow water, and the centerboard's often getting coaxed up and down by the bottom.)  If that whole thing were cleaner, and the the trunk capped, then that makes a great unbroken surface when the floor panes are raised.

I'm also thinking that instead of cleats for the panels, a few of simple removable aluminum supports running athwartships and Z-shaped on their ends (over the seat tops, then under the panels) would do the trick.  They'd be very easy to stow wrapped with a bungee and shoved in a locker.

[wkisting]

Scott,

I just modified my CB downhaul to get rid of all the rigging alongside the trunk. Now I run a single line from the head of the CB, down through a block, straight aft to an "Autorelease Clamcleat" (model CL257) on the thwart. It significantly reduces the clutter alongside the case, and works better too since I can force the board down easily by pulling on the line (on the old setup, the bungee was too stretchy, so I always had to reach ahead and grab the line further up, which was inconvenient).

The starboard (right) side of the case used to have the elaborate bungee mechanism for the downhaul, but as you can see, it is now just a single clean line on the port side of the CB case, next to the uphaul. Very handy. The main reason I made the change was to clear space for a berth expander panel on the starboard side footwell, but I would've made this change anyway (even if I don't end up making a berth panel) because it is much simpler and works well. On its lowest setting, the clamcleat releases at about 30 - 50 lbs. of force, making it ideal for holding down the CB but allowing the kick-up function if you forget to release the board.

Here's a pic...

[PAR]

I made my case and hoisting changes from the start, which made a substantial difference in many of the build elements. For example the seat tops and the case cap are the same height. As you can see the case top is smooth and flush. The cases sides were reshaped to permit a different shaped board. The forward end of the board has part of a circle profile. This permits the curved edge to remain in contact with the top of the case, where the stringers live. This was an important strength consideration, because without the arm, the strength comes from the top of the board bearing against these stringer areas.. You could retro fit this feature on a stock board and case, but it wouldn't be as strong.

The board was weighted with about 18 pounds of lead. It drops very well and still kicks up when necessary.

The simple tackle isn't visible in the picture, as it was installed yet, but in reality, the only part you see is the tail and cam cleat under the thwart at the centerline. The hoisting lanyard (tackle) hides under the case stringer and passes between the mast and the case to a cleat mounted under the thwart. Everything else is under the forward portion of the seat (see drawing). The forward king post is also vertical rather then canted aft as shown in the drawing and the hoisting lanyard comes out of the case in a straight run to a single block mounted on the forward bulkhead, not angled down as shown. I did this to eliminate the king post mounted sheave. I used a piece of HDPE in the lanyard exit hole instead.

[JeffM]

I've thought about such a cb mod, partly to free up space in the cabin, partly because my cb case spits a fair amount at speed.  the strength issue hadn't occurred to me, though.  I'm intrigued by the tackle; I'd assumed I'd need to put a an uphaul to the lower end of the board, leaving it dragging in the water.  Paul, have you ever had your tackle foul, slipping between cb and case?

[PAR]

It can't, as it rides in a grove routed into the curved portion of the board (one of the reasons I curve this area) which is too close to the case cap to permit it to jump out. The image is crappy and during the rough shaping of the board stage, but the groove is clearly visible, so is the knot hole for the lanyard.

[JeffM]

Very nice! Thanks!