Monday, February 26, 2007

Bow web laminations part 1

First I had to wrap the web with one layer of the 8.9 ounce s-glass cloth with the fibers at 45 degrees. Then a second layer over the top 3 inches around the G10 tube. I must admit that I could not wrap this 'odd form' part with one piece of cloth. Practically, I wrapped the cloth around the G10 tube (pulling it tight) and used separate bits to cover the edges where required. I then sanded the part to make it smooth.

I used a steel rod clamped in a vise and pushed through the G10 tube to support the web when I applied the cloth and unidirectional carbon fiber tape.

Here is the web after applying the required vertical strips of overlapping unidirectional carbon fiber.

It does not really show in the picture, but the part at this point sure looks like it has some mean character!

I then sanded the edges smooth. You can see how much carbon fiber is built up around the tube.

Next step is to fill and smooth the part with a low weight epoxy putty.

Sunday, February 25, 2007

How to build rudder blades and centerboards

I was generously sent some material from an interested F-22 builder in my area yesterday.

How to build rudder blades and centerboards

The article makes me think about the question of material for the daggerboard. Should I use shaped foam or edge glued red cedar? I'm imagining the flow around the aft edge of the board at 15 knots.

Here is a section from the link that I find very interesting about the trailing edge.

Here is a technique for fiberglass covering that has proved over the years to provide a long lasting trailing edge. When rebuilding an existing blade or before applying fiberglass cloth to a new blade, plane a flat on the trailing edge about 1/8"-wide (wider for large rudders and centerboards). When applying the fiberglass cloth, position the rudder or centerboard horizontally so the leading edge is up. Drape the fiberglass over the foil and trim so that it extends 1/2" past the trailing edge. If you make a full-scale drawing of the trailing edge of your board or rudder, you will get a better idea of exactly how much fiberglass cloth to leave.
After the fabric is wet out, use an #807 syringe to apply epoxy thickened to a non-sag mix with 406 Colloidal Silica to fill the gap between the two layers of fiberglass cloth. Squeegee out excess epoxy and align the trailing edge so that it is straight. If necessary, clamp a plastic covered straight edge in place to make the fabric conform to the shape of the trailing edge. After the epoxy cures, do the final shaping with a sander or sandpaper and a block of wood. Use caution, the edge can be very sharp!

Sunday, February 18, 2007

Daggerboard case mold

It has been a hectic week at work. Some goals for the boat build that I had made last week, have not been fully achieved. However, some progress has been made.

I have cleaned up and reorganized the basement to make the space required for the bigger flat panel table. I have space now for a table as large as 4'x12'. This larger table will create the parts for all the remaining flat panels from the float decks to everything in the main hull.

That's ~6' long dagger board mold construction parts in the above picture. Note that with the 3/4" thick mdf boards almost sealed - it almost looks like a piece of furniture!

In the above end view, note my interpretation of the appropriate 'slight taper' called for in the drawings.

Lake Ontario again. (It's where I live). Above picture shows the 1-2 meter build up of ice on the beach where our new puppy Colt (6 month old Australian Shepherd) likes to run.

Don't go out any farther Monica!

Sunday, February 11, 2007

Bow web pre-lamination

The continued cold weather, shutting down work in the garage, has given me the 'opportunity' to work on other parts of the boat.

With some Corecell A1200 high density foam (a pale yellow colour) now in hand I decided to put together the pre-lamination parts of the bow web. The next step will be to laminate this with wraps of fiberglass and strips of carbon fiber. The bow web, I believe is a new feature of the F22, not found on other Farrier designs. The design does a number of good things.

  1. Eliminates another metal part. It looks like synthetic rigging is standard on this design. Check out Precourt Systems.
  2. Organize furler systems for the jib and optional genoa.
  3. Provide a mounting point for the bow sprit, which will be removable with a pin and not retractable.
  4. Keep the sails down low to the deck.

The part went together quite simply.
  1. Glue 3/8" thick 5lb foam together to to make the 3/4" required thickness. I actually used some smaller foam offcuts for this part. You can see the join in the pictures.
  2. Trace the shape from the supplied full size template.
  3. Cut it out.
  4. Cut to size the required high density foam inserts for supporting the G10 tube and the area where there will be a hole drilled for the bow sprit pin. Glue them into place.
  5. Mount the G10 tube in place on top of the high density foam and fill in around the tube with a putty (microballoons) . I purchased the G10 tube from Ian Farrier as I could not find a convenient supplier for this material in such small quantity. I thank Ian for sending me a contiguous 13 inch length of the G10 tube.
  6. Sand and smooth as specified.

It's pretty much ready for laminating.

Wednesday, February 07, 2007

What version of the F-22 trimaran am I building?

Well, the continued cold weather here has given me the opportunity to think forward and consider work that will require some decisions. Ian Farrier has created a basic design with a large number of options that can suit both cruising and racing requirements. As a person interested in good design with consideration of the best engineering compromises, I find myself still committed to building a boat that can win races but will still also allow for short term multi-day cruising .

Therefore, for those interested, and to make my decisions final I have decided to build the following

  1. Aft cockpit version
  2. Full cabin
  3. Daggerboard
  4. Boomless main
  5. Optional pop-top
  6. Materials and techniques for the F-22R designation, including all carbon fiber on the daggerboard and rudder
  7. No raised floor
It will look much like the picture above.

But hold on, wait, it will not have a red hull!

More likely it will have a black hull with white decks and with some fancy Raven icons embedded in white and red on the hull.

I'm off tomorrow (at lunch break) to buy high density foam, carbon fiber tape and carbon cloth to enable the fabrication of the bow web, daggerboard case and daggerboard. I'm also planning to set up a bigger vacuum bag table in the basement for making the larger flat panels for the main hull.

Sunday, February 04, 2007

Second set of float bulkheads complete

I have finished the last set of float bulkheads and have the foam stringer all ready to go. As a pure photo opportunity I set them all into position (they stand on their own). When I took this picture the temperature was -10 degrees Celsius. I've been waiting for the temperature to warm up a bit but I can't wait much longer. I have two propane heaters (kindly donated by my brother-in-law) that I am now prepared to fire up and hand lay up the inner hull, foam stringer and tape the bulkheads into place.

I really want to reverse the form frames and get the last two float halves finished.

Here is a close up of the access port cut into the aft beam bulkhead. The exposed foam was dug out and the edge was filled with putty to make it robust.

It's a small world. I took this picture yesterday walking the dog. It shows a view of Lake Ontario from Guildwood atop the Scarborough Bluffs. Bluffers Park can be seen in the distance. It will be one definite launch point for my new trailer trimaran.

Thursday, February 01, 2007

West coast of North America, 'Raven' mythology

The Beginning

In the beginning there was nothing. Only water, darkness and The Raven.

He flew through the darkness with a bag that hung around his neck. He had been flying for a long time, and was starting to get tired. So while he flew, he removed a rock from his bag and threw it into the sea. This rock became the first land. He sat down upon this land to rest, while resting he took other rocks from his sack and threw them into the water. Thus The Raven made the land.

Rested, The Raven picked up his bag and continued to fly. After a while he became tired, so he sat on a rock and took more items from his bag. He removed the fir, the pine, the spruce, the redwood and all the trees of the world. He also removed the huckleberry bush, the wild strawberry, the grass and all of the plants of the world, including the plants of the sea. These things he scattered across the land and the water, so that they may grow.

Again The Raven took his pouch around his neck and flew through the darkness. And again The Raven became tired so that he sat upon a rock. This time he removed all the animals of the world. The wolf, the eagle, the salmon, the bear, the dear, and all the animals of the land and of the sea.

The Raven looked around him at the world he had made, it was a good world, every one was peaceful and happy. But before he flew off he looked into his pouch and saw that there was one thing left. So he removed man from the bag and placed him upon the earth.