1.04.2010

YIKES!!!!!!!


This photo scares the crap out of me.......I doused the lights in hopes that it would show the laser grid lines that I was using to align the port side centerboard location and now I see some creepy red eyed catamaran monster looking back at me from the port side state room.



Now how many times does a person get to use space age lasers, cardboard, box knives and masking tape all in one day? Here's a confusing shot looking at the port side centerboard case location. ( Ive taken it out again to add all the reinforcement webs)

  The forward portion of each case requires a series of reinforcements that transmit loads generated by the boards back into the hull so Im using a really nice laser level that my brother gave me for christmas to create patterns that I will use to cut the foam core pieces.  

1.02.2010

Starboard side centerboard case.


Pre fitting the starboard side centerboard case.  Fot this photograph, I'm standing in the port side forward cabin looking aft.  Takes a bit of trial fitting..... marking interferences, grinding away at them re fitting it, marking more snaggs puling it out again and again.  If you look real closely you can see a 2 inch wide grey strap that I tied into a loop.  I finally figured out that tucking my shoulder under this strap lets me lift the case out by my self without much effort.  Also note temporary stairs leading down from the bridge deck.

12.16.2009

It fits.....


This is where the port side centerboard case will live out it's useful life.  I've positioned it in place temporarily and will remove it so that I can install the other support webs.  The case is offset nicely and it leaves plenty of walk way floor space inside the hulls. Notice, however, I have not yet installed the floor supports so you are looking at the curved bilge of the hulls.  Also you will notice that the case fit is not yet complete because the top portion of the case needs to lay flush with the top surface of the side web.   Regardless, I will sleep better tonight knowing that it is going to be possible for me to actually build this cat with centerboards........As Ian Farrier says : It's a lot more work. He's right but I still want to be able to run this ship over unseen sand bars without having to worry about smashing a dagger board or ripping an unwanted slot in a hull. 

Stressful sawing


Cutting a gaping hole in the bottom of the port side hull was a stressful thing to do.  After days and days of stretching string lines, making measurements, swinging plumb bobs, wielding levels, shining lasers and pretty much convincing myself that I knew where to cut my centerboard case hole, I went ahead and cut it......will the case fit...... or will I have to build a new boat?  The wood piece is a representation of the cross section of the centerboard case and here, I am using it to check the fit of the case before I man handle it in place.

Marking the location for the port side centerboard case install


Although this is not the most elegant photograph of the interior of the port side hull, it shows a number of sharpy pen marks that I have made to convince myself that I know what I am doing. ( measure five times, mark three times and cut once )

You can also see the multi layer unidirectional upright web along the left side of the door opening. This, along with several more reinforcing webs will provide ample bonding points to distribute the forces that will be generated by the centerboards.

Port side centerboard case trimming


The forward end of the centerboard case nests into the inner hulls forward of the mast bulkhead.  The lower edges of the case protrude through a slot cut in the boat and will be trimmed to match the curves of the hull.

12.09.2009

forward end of port side centerboad case


Here's a close up of the forward end of the centerboard case awaiting an end cap of glass and epoxy.

Port side centerboard case


Here is the port side centerboard case resting on top of the port side master cabin top.  This was as good enough place as any to prepare the edges of the box for external glassing.

12.07.2009

reason enough.....


Here are 16 reasons to build a cruising catamaran........nice compared to 9 degrees outside the shop.  Tonight, it's colder here in Hood River, OR than it is in Anchorage Alaska.  The extension cord is running to a small heater inside the bridge deck cabin keeping it a comfortable 75 deg. inside the boat. Maybe I should think about naming her "Thermos"

12.05.2009

clamping the centerboard case sides together


With a record cold front on it's way to the Pacific Northwest, what is beginning to become the port side centerboard case is nice and warm inside the main bridge deck cabin. Notice  that the little 750W heater has kicked itself off and it is not having to work too hard to keep things tropical inside.  Outside, the first winters snow is beginning to fall on the metal roof of the shop. 

joining the centerboard cases sides


  To control the precise distance between the centerboard case sides, I've wrapped a 4 x 6 inch wood with tape so that I can use this as an internal spacer.  Next, the plan will be to lay glass and epoxy over the  spacer, add foam along the ends and clamp the centerboard sides in place. Once the epoxy cures. I'll remover the spacer.

12.02.2009

Setting up the boards for some hand shaping



Here I am preparing to hand shape one of the centerboards. The Oregon sun was low and strong on this 2nd of December and in honor of such a beautiful day, I decided to set things up outside.

You'll notice the recessed spar which will be covered with 15 layers of 12 inch wide uni glass in between  two layers of 24 oz triaxial glass. Since the final external dimensions will be critical,  it will take a bit of skill to shape these blanks while taking into account the required schedule of glass. Not only will I need to achieve the perfect foil section, I'll need to be able to do that by anticipating the thicknesses of individual layers of glass that will be layed in various places throughout the board.  for example; the leading edge of this board will be covered with additional layers of glass so I'll need to create a recessed leading edge so that it can be built up and fared to the correct external final shape.....it's sort of like trying to work backwards in time.

12.01.2009

checking the fit...


OK, since I had to cut the spar out of my blank, shape it, impregnate and glass it with epoxy then bond it back in, Here's the board blank with the spar core pressed into it's home again. Next step will be to bond it back in place using a good thick mixture of micro / cabosil and epoxy.

Tomorrow I'll have a go at these blanks with a power planer and shape them like two big long boards. That will make for a good day.......maybe I'll add a fin box and take one to the Oregon coast for a surf session. or....maybe mount a mast base and windsurf it here in the Columbia Gorge.....or give it to by buddy Cory to do some free style strapless kite boarding with it.......

de bagging the centerboard spars


Here's an interesting way to open a vac. bag.....

Fitting the centerboard spars


Originally, I created my centerboard blanks with the high density cores  (mahogany spars)  all in one. but I decided to laminate, shape then wrap the spar cores individually with glass, then insert them into my centerboard blanks before the final shaping.   Fortunately, I was able to utilize a good portion of my excess foam "cut offs" to create the centerboard blanks by cutting the smaller  foam  pieces into strips and vac bagging them all together.  Notice the board blank on the left is being fitted with the spar.  

11.30.2009

a simple post cure oven


so here's a quick post cure oven that I put together to cure my centerboard cores. tomorrow I'll pop them out of the bag and you'll be able to see what this is all about. I placed both spars inside this foam box and used small blocks of styrofoam to close in the edges between two thick foil covered foam sheets. Notice the heater in place as well as the vacuum pump sucking away.

Centerboard spar cores


After laminating, planing, shaping and tapering the centerboard spars, I am preparing to glass them and insert them back into the centerboard blanks.  In this case, I chose to use a light weight mahogany core material as my "high density" spar core.  Once these spars are embedded into the centerboards and laminated with 15 layers of 12 oz unidirectional glass,  these spars will become the primary structural elements in the centerboards.  Here, I am simply pre fitting my glass in preparation of vac bagging the glass onto the cores.  In this case, I used 3M 77 spray adhesive to keep my glass in place then I mixed a whopping amount of epoxy and rolled it on thick.  I then wrapped the spars with peel ply and vac bagged them to insure that I would get good saturation and bond between the wood and glass.  If I do this right, the wood will never know it is part of boat.  ( Being fully encased in glass and epoxy,  hopefully this wood core spar  will never see one molecule of H20 as long as I sail ) 

11.06.2009

F-44SC Catamaran: mast base core

F-44SC Catamaran: mast base core

mast base core


Here's the mast base core.  This chunk will be fully encapsulated with epoxy and multiple layers of glass. I elected to laminate this piece from White Oak.  White Oak is known for it's durability and resistance to water.  ( White Oaks have cellular structures called tyloses. Tyloses give the wood a closed cellular structure, which does not allow water to pass.) further knowledge on White Oak: http://en.wikipedia.org/wiki/Quercus_alba

To further reduce ANY possibility of water intrusion,  all fastener penetrations will first be drilled out oversize with a large paddle bit then the void will be filled with solid epoxy, micro,  aero fill so that any fasteners will have no contact with  the wood.