centerboard case sides

Finally.......all four centerboard case sides out basking in the yard.

The wide ones become the inboard case sides. Notice all the reinforcing ribs and high density top edging. I decided to use Luann Mahogany for the high density core edging along the top portion of the case sides.

infusing a portion of a centerboard case

Sometimes it's a toss up as to when to use the resin infusion process. In some cases, a controlled infusion of resin can be a good way to insure a strong part. Other times, it can turn out to be a big waste of time when the same thing can be accomplished with conventional wet layup w/ peel ply or vacuum bagging. One nice thing about the infusion process is that, if done properly, it can be a neat and clean operation.

Clamping things with clamps

a man can never have too many clamps......

center board cases

Here's on of four centerboard case sides being fitted with various high density edge cores and extra glass. I'm using a medium weight Luann mahogany for my "high density core material. This top case edging will be covered with 32 oz glass and vacuum infused.

Bagging the inner, port centerboard case side

Since my vac bag table spent the winter outside in the rain, I had to spend a little extra time preparing it to be used again.

This time, I screwed three full sheets of tongue and groove 3/4 in plywood to a framework of 2x4's and sheathed the whole thing with a 15 X 9 ft. sheet of thick rubber pond liner. My logic here is that I only have to use one sheet of vac bag every time I create a part because I am able to simply seal the top membrane to the lower rubber sheet and use it over and over again. By placing the entire platform up on a few sets of car jack stands, It also provides a nice comfortable , clean work surface.

In this photo, you can see the yellow rubber vac bag tape along the edges of the rectangular vacuum bag area. Also, here are a few more things to notice:

the vacuum manifold can be seen inside the bag on the left. To distribute the vacuum pressure, I use a 1/2 in piece of plastic cpvc pipe with lot's of holes drilled in it. This gets wrapped in breather material and insures that good uniform vacuum pressure is maintained along the entire part.

center board blanks

Time to shape some surf boards..... These things are almost 10 ft long. The upper board blank is still in the bag that I used to vac-bag all the foam pieces into one big board. If you look closely, you will notice cross cuts in the board stringers. These cuts were made to help me gage the thickness when I go to shape them down to size. ( before I bonded all the foam in place, I used a skil-saw set to the precise depth that corresponds to the thickness of the boards called out in the plans.)

laminating the centerboard stringers

Inside of the twin centerboards of this cat will be the most beautiful lightweight straight grain mahogany stringers that the world will never see. Here, I'm using a vacuum pump to help laminate two sets of four 8 inch wide by 78 inch long boards. These boards will then be shaped and then bonded with 45 x 45 x 0 glass and will become stringers that will then be embedded into two separate foam blanks. These stringers will then be shaped and capped with multiple layers of unidirectional glass and the sections that will swing down into the water will be shaped into symmetrical foils.

The next blue sky will find me shaping them with my power planer like two big honkin surfboards.

Varifying the varifications.....

It's always good to have someone check all the layout dimension before taking a power planner after anything. although it's always possible to glue foam back into place if you make a mistake, it can save some time. Here, the inspector is checking the location of the centerboard pivot pin. He has also made various marks on his legs........perhaps to test the functionality of the writing instruments.

the boards

So here's the full size template of the centerboard. The gap in between will actually measure 27 inches and both of the templates are seen here taped onto a 4 x 8 sheet of core cell.

The plan is to slice most of my scraps into uniform widths, laminate them into a 4 sheet thick plug and vac bag the block into one solid blank. Various sections are comprised of high density material ( I'm planning on using straight grain 1/4 sawn Douglas fir for the internal sheer portion of the spar. Since this piece is going to be encapsulated thoroughly and capped with multiple layers of glass and epoxy, I will not feel that bad about using wood as an internal spar.

Next comes the fun part. The plan is to build a 3D Cad file of the boards and have them cut on a CNC router. If it was summer, you can bet I'd have these things on a couple of saw horses in the sunshine and just shape them with a power planner like two long boards .

Soulfull tools

Special thanks to Barney of Hood River, Oregon for passing along his Grandfathers saw. I think most good tools seem to hold the presence of past owners. This is a good because table saws, in particular, have been known to throw things across the shop for reasons unknown to the living. New table saws do not come with the watchful presence of past owners.

It's good to know that Barneys grandfather and I will both be watching out for my fingers.

"Center" board cases

Although it would certainly be easier to fit this ship with dagger boards. I like the idea of making sure that when she runs aground, the boards will simply kick back into the hulls. Here I've lay ed out the board case sides and have pre-cut all of the High density foam inserts that become integral parts of the case sides.

The case sides are comprised of 3/4 in. 5 lb. corecell with various inserst of 12 lb. foam to strengthen high stress points.

Doubling up the sternI uI

 
 This first photo shows the extra pieces that I have cut to add thickness to the hull stern flanges. Notice the slim crescent shaped flange thickener that I have preformed to fit the trailing edge of the stern.  

Here's a shot of all the pieces after they have been bonded in place. I used a v grove flooring adhesive spreader to coat the bonding faces with a generous amount micro thickened epoxy.  

    

in the bag....

After gluing, screwing and clamping all the preformed foam in place, I covered the assembly with a piece of used vac bag sheeting and tucked a little 1500W heater under the cover and called it a good night.......Although the shop temp was around 35F, the aft steps felt like they were in the Bahamas........wishful thinking I guess.

roughing in the aft starboard boarding steps

Although it's darn cold in the shop, I was able to use my easy bake foam toaster ( seen here lower right) to thermoform the end radiuses in the step faces. My technique has been to form and fit most of the pieces and temporarily screw them in place here an there with some sheet rock screws. After everything fits the way I want it to, I come back and mark all the critical join areas with a sharpy ( A ----->A, B------->B, etc ) It also helps to label "up" in case your boat flips over or you fall off a ladder and get disoriented.

Fancy foam fitting feat

Here's a simple technique for fitting a strip of foam to an irregular curve. The foam piece that you see mid photo needs to fit against the lower surfaces so I've temporarily clamped it a full width higher than it will eventually sit. I then took a scrap or stick and used it to scribe the curve by moving the stick up along the curve while making dots with a sharpy. From there, it's a pretty easy exercise in connecting the dots and cutting the excess off. You can spend a lot of time making paper templates and trying to cut things perfect but using little tricks like this can help keep things moving along.

starboard boarding steps

You're looking down at what will eventually become the starboard side stern boarding steps. I've taken a little extra care to sculpt some nice rounded curves to avoid having corners that may some day bruise the hips of careless bikini clad super-models if they try to board the boat in a chop.

more stair work

Here I've added the extra thickness along the edges of the stern. All this foam work will get sanded and shaped smooth. the hull edges will also be gouged out and capped with the usual mix of epoxy, cabosil and microbaloon filler then I'll glass this grand stairway and move along to the starboard hull. When ever I feel like I've made some progress, I look up and realize that there's another hull waiting for me.

port side boarding steps

Here's a little progress made towards building the aft steps. I haven't built the lower step and this will involve boxing in a structure that will house the rudder bearing and it will have the ability to pivot up. I chose to create a slightly rounded cascading detail that eliminates any exposed step corners. Also, the next step is to add another layer of foam along the stern hull edges. The fun part will be going at this thing with a bunch of sanders and shaping tools so that it'll have a nice sculpted form

port side stern steps

Here's a start roughing in the boarding stairs for the port side hull. I chose to go with the boarding platform and radius the stairs to eliminate exposed corners on the steps. I also decided to go with the under slung kick up rudder box so after I build the stairs, I'll go after them with a saws all and create the rudder support portion that will kick up.

unde cover

snug and dry inside the shop......

tucked in for the winter

This is the first posted photograph taken with my new Canon Rebel digital camera. From here on out, hopefully you should see an improvement in the quality of my photographs.

Here's a shot with the morning sun shining through the starboard side hull foam. The make shift scaffolds allow me to risk falling to my "harm" onto the cement floor between the two hulls. Since the cold won't really allow me to lay up the bridge deck floor, I'll most likely build a better temporary walkway between my hulls.

Stern view

Here's a 3/4 stern view. Lot's of work to do but it's nice to see all this expensive foam, glass and epoxy beginning to look like a ship.

Putting the pieces in place

Since the Pacific NW chill is beginning to make her way off the cool Pacific and onto the North west coast, It's time to put the pieces together so that I can set up a protected place to work....mainly "Inside" the boat. I decided to position the hulls as they will eventually go, throw a big 6 MIL plastic cover over the shell and create a snug place to work me through the coming winter months. Of course, the curse to avoid is becoming bogged down in details at a time when large brush strokes are still required.

brother kevlar

My brother flew in from Santa Cruz to help me sheath the port side hull with Kevlar. Unfortunately, "Big Brothers" latest wars have made this stuff fairly expensive. With new leadership, America will most likely be able to reduce the need to turn this stuff into vests. I think it looks better on a boat than a desert tan Hummer.

port side bullet proofing

One advantage of finishing the bow beam is that you can use it as a scaffold when you're sheathing the port side hull with Kevlar. I used three 1 ton harbor freight chain hoists and a few straps to flip my hull upside down. Here, I'm applying resin before laying down my 9 oz. Kevlar along the keel and bow section.

Kevlar option

I chose to go with the optional 9.oz Kevlar sheathing on the hulls. This option begins by laying down 8 inch wide, 9 0z. unidirectional kevlar along the hull center line "keel". This is then covered with 9 oz. twill kevlar fabric sheathing from 48 inches aft of the mast bulkhead, forward to the stem and 8 inches above the waterline. Kevlar is very difficult to wet out so using slow hardener, lots of patience and peel ply over the big sticky mess is about all you can do.

Someday, maybe I'll feel better about myself after I beach this ship onto the only hidden rock on the sandy beach.....

another view...

here's another view of the same. I was able to hand work the entire length of the boat one section at a time. By working about 6 ft. of epoxy, glass and peel ply at a time, it is possible to control the resin glass ratio to a high degree. any excess resin is simply moved along onto the next 6 ft. section. and on and on and on until the carpel tunnel syndrome kicks in. NOTE: high density foam core keel section can be seen lower right hand.

final outer starboard hull laminate

Although it's not advisable to skip too far out of sequence, I'm guilty of putting off laminating the final outer starboard hull exterior section. Here's the result of my weekends work......8 hours sat; 11 solid hours sunday laying two full runs of 34oz. triaxial glass, resin and peelply. Note 3" overlap section recessed into foam w/ power planer.

Also, In the upper background, you can see my cabin top. In order to preserve shop space, I winched it up into the rafters and tied it off.

back to the cabin top[

Here's the final run of "B" (24 oz. glass) going down over what will be the interior top of the cabin. This photo shows my 10 step lamination technique.

1) lay foam over stringer mold
2) fair all glue joints
3) skim foam with a slurry of epoxy and micro balloons
4) roll wet coat of epoxy over foam using a 3" paint roller w/ 3/8" fur
5) lay glass over wet coat
6) wait until the glass soaks up from below
7) roll another wet coat over glass
8) lay peel ply over wet glass
9) wet top of peel ply with left over epoxy that is on the roller ( this makes it easier to work)
10) work excess epoxy from center to edges using bondo spreader.

bonding the big burly bow beam

Here's a look down the inside of the bow beam. For bonding, I used System three Gel-Magic which is a thixotropic structural epoxy adhesive. It's a pretty handy epoxy "glue" that mixes 2 to 1 like epoxy but it's formulated to turn itself into a gel that will stay put. I spread a decent amount along both bonding surfaces, placed the top chanel over the bottom, rolled them on their side and fixed the bow beam together with temporary screws. The photo confirms that I have 100% internal squeeze-out along the entire length of the seam.

poping the 2nd bow beam section out of the mold

Including building the mold, fabricating the two 19ft. bow beam sections has taken about 16 hours. Considering that I am paying myself 0 dollars / hr, that comes to a total labor cost of 0 dollars. Shown here, after popping it out of the mold, is the 2nd half of the bow beam section. Next step will be trimming it down to spec, bonding the two halves together and skimming the beam with a mixture of micro spheres and epoxy to smooth down the seams and minor imperfections. To eliminate bonding prep work I placed peel ply into the mold top and bottom. Peel ply is my friend.

Solar post-cure using the green house effect.

After bagging one section of the bow beam, I used pressurized air to blow the bag up and then set it out in the sun. Thanks to the green house effect, on a sunny day, the temperature inside the bag can easily reach upwards of 120F.

Inthusiasm

It's nice to have enthusiastic workers to keep the project moving along.

Composite bow beam mold

Here's my helper smoothing down the packing tape along the length of the bow beam mold. The two upper cap beams are in-set about the thickness of what I think the sides will be; thus forming an internal flange. After layup and vac bagging is compete, I'll remove the cap strips and lay up what will become the other half of the full 19 ft. length. Then the two channel sections should fit together and be bonded to form a composite beam that is 7 in. tall, 9 1/2in. wide and 19 ft long.

mast base core installed.

The one inch thick end grain core insert is now in place. To the left, you can see the piece that I cut out. Again, I used system three polyurethane glue and made sure that it was flush to both the top and bottom surface of the one inch thick core cell deck foam.

installing a high density core section

The portion of the deck in front of the cabin gets a very high density insert. Here you can see an 8" x 16 in. end grain oak core that will transfer the compressive loads of the mast into the deck, the mast bulkhead and the forward center section bulkhead. Your looking at the under side of the forward portion of the cabin top.

getting closer ...

So I've used my oven to form all the foam to fit the cabin top mold. I've used two inch squares of 3/8th in. plywood and sheet rock screws to hold the planks in place. Once all the pieces are "dry fit" together, I found it easier for me to start from the middle; edge gluing the planks together one by one.

I'm using SYSTEM THREE polyurethane glue ( similar to the one part, moisture cure, Gorilla glue)

another angle

This is actually the inside of the starboard side cabin top......seen here up side down.

My toaster oven

So you're looking into the inside of my heat lamp powered thermoforming oven. It's made from a few two inch thick 4' x 8' sheets of foil backed insulation foam and a total of ten 250 Watt heat lamps......... takes 6 minutes to heat the foam until it can bend easily.......7 minutes and it puffs up into very expensive landfill fodder.....When this oven is on, I have to turn up the radio to drown out the jet engine like sound of my electric meter.

Laying down the cabin top foam

Here's an action shot of the 1 inch foam going down over the cabin top mold.