Monday, April 19, 2010

Foredeck Beams

I'm starting the long process of framing the interior of the boat.

The curved foredeck beams have been cutout and installed. The pattern for each is given in the plans. The plans didn't say how to attach them exactly, so I just glued and screwed them to the side of the frames and the inside of the gunwale. I made a small notch in the gunwale for the deck beams in between the frames to make it easier to screw on. Also, a strip of 3/8"x3" plywood called a king plank is checked into the top center of the foredeck beams.

Then I carefully trimmed the gunwale shear line to align with the frames and deck beams. (I used a circular saw which is actually an accurate trimming tool that's faster than a hand plane if you have to cut off a lot of material.) The plywood deck will be attached to the frames and the gunwale. They all have to align with no gaps.

Two carlines are also installed aft of the foredeck beams. These match the curve of the gunwales, but are angled inboard, as you can see in the pics below. They are angled this way because the cabin sides are going to be secured to the side of these carlines and the cabin sides are angled.

Here's a good pic of the connection of the cabin beam, gunwale and carline. You can see the cabin beam slightly checked into the gunwale (not too much so to not weaken the gunwale). Some people prefer not to check into the gunwale at all, but I found it easier to assemble this way. Also you can see a funny shaped spacer block that the carline is secured to.

Bending these carlines into position was unexpectedly very difficult. It required a compound bend in two directions. After breaking the first one, I cut out a piece that was slightly curved downward (about 1/2") in the middle, eliminating the need for a compound bend. This doesn't sound like much of a difference, but it significantly decreased the force required to bend the carline into position.

On an unrelated topic, I made a new scarfing jig. If you recall from almost a year ago, I made a scarfing jig to use with a belt sander (which is almost comical to think about now). Here is the new one that works with my table saw. It just keeps the piece being cut at a 12:1 angle. It couldn't be simpler really. I've been using it instead of the belt sander jig and I thought I would show it on the blog just to be thorough. I'm going to need it again soon to make the shear capping pieces.

Sunday, April 18, 2010

Jib Sail Finished

I finished the jib sail. Here is a pic of it being folded up for storage. Notice all the jib snaps installed and the leather sewn on the corners. (Never mind the dog grazing on sewing scraps.)

I also made three duffel bags for the three sails following purchased plans. The duffel bags are made of nylon and pretty easy to sew. Making all three of them took me about 5 hours. The piece of fabric is folded in half and sewn together, then the bottom is cleverly folded to make a square and sewn down. The bag is then just turned right side out. There is also a draw string pocket along the top. The jib sail is in one of the bags in the pic, but the other two are empty waiting for me to make the other two sails.

But the "sail loft" is now cleaned up and mothballed for now. I just wanted to make sure that the sailmaking wasn't going to cause me any problems and it isn't. I'm going to get back to working on the hull now.

I apologize if the sail assembly portion of my blog isn't very detailed. If you want to learn more about the sail kit assembly, I figure you can just go to the sail maker's website and watch streaming videos. I just want to share my personal experiences like:
- yes, I can sew sails with a crappy home sewing machine.
- making a sail pattern before sail assembly for future use.
- details about my specific sails, etc.

Wednesday, April 7, 2010

Working jib sail almost complete

I almost finished sewing the working jib sail.

My first stitches are ugly ... but they are slowly getting better. I spent about 4 hours learning how to use the sewing machine and adjusting it using some scrap fabric. After a lot of "bird nests", I got it under control. But then when I started sewing the sails, I had a whole new set of problems. The hardest part is feeding the large pieces of fabric through the machine and keeping the stitch straight and evenly spaced. Having an uneven stitch just looks a little funky and doesn't seem to affect the seam's strength too much, so I'm not too worried about it. (Luckily the sail maker sold me white thread that matches the white fabric, so sewing mistakes are not too conspicuous).

The sailmaker sold me a bunch of double-sided basting tape. Sewing the sails would be impossible without this stuff. Even the pros use it. I basically just tape everything together before sewing and then nothing moves when it goes through the sewing machine. The tape just stays hidden in the seam permanently after sewing.

My cheap little machine sews through very many layers of material surprisingly well. At one corner of the sail, I sewed through 8 layers of 4.4oz sail cloth and two layers of thick webbing.

So here's a little description of how this sail is constructed. The horizontal sail panels are sewn together with a 5/8" overlap seam with two rows of zig-zag stitches. The corners are reinforced with 4 layers of additional fabric patches. Here is a couple of pics after the panels and corner patches were sewn together, but before the edges and corner hardware are done.

At each corner there is an attachment point for halyards and sheets (ropes). One corner has a D-ring. The D-ring is attached to the sail with multiple pieces of webbing that are sewed onto the corner patches. The other two corners have wire thimbles. The thimbles are attached to a wire that sewn into the luff edge of the sail (kinda like pipping on upholstery). Each of these attachment points is heavily reinforced with thick twine that is hand sewn. The thimbles are further reinforced by a brass ring that's sewn into the sail next to it, then twine secures them together.

All the hand sewing is done with very heavy sailmaker twine. The hand sewing was pretty easy since I used an awl to pre-poke the holes and a coin to push the needle through. The corners are dressed with little pieces of leather, which is just there to prevent chafing. Here's some pics of the wire thimbles and wire sewn into the sail. (The leather is partially sewn on at the moment.)

Bronze jib snaps are attached behind the steel wire all along the luff edge to attach the sail to the fore-stay wire on the boat. You can see one of these snaps installed in one of the pics above. Without this wire in the sail, the grommets that the jib snaps attach to would just rip out of edge of the sail.

The other edges (the foot and leech) are just double-hemmed.

So I just have to finish stitching on the leather patches and then I'll have a perfectly functional jib sail (with some comically ugly stitches in a few spots ... but oh well).

Sail loft getting ready

Here is a glimpse of the sail loft. A nice little yellow spare room.

I purchased three sail kits (main, jib and storm jib) from a sail maker. These kits have all the hardware and materials (fabric, thread, twine, rope, wire ... everything I need) and instructions to assemble them. I just need to sew the sails together (mostly machine sewing but some hand sewing at the corners) and attach the hardware. The sail fabric is already cut out. For those of you not familiar with sail design, the sail maker designed the sail panels with curved edges so that when they are sewn together they will form an airfoil shape. (Not something I can learn to design without sail design software.)

I'm going to try to sew tough sail fabric with a cheap little Singer sewing machine from Target. I'll let you know how it goes. The sail fabric is called Dacron, a surprisingly tightly stitched, plastic-like polyester fabric (kinda like Nylon, only much more stiff). I have to learn how to use the machine before I can sew the sails. The stitches of my first sail will probably look bad, but hopefully I'll get a hang of it. I'm going to make one sail (the jib) just to make sure that I can do it, then get back to building the boat. After the boat is closer to completion, I'll make the other two sails.

But first, I made a full-size pattern of the sails for the day when I want to make replacement sails. (Talk about thinking ahead, right?) The sail maker was kind enough to give me a computer print-out of the X,Y coordinates that he used to cut the sail panels out with a large automated plotter. I typed these coordinates into AutoCAD to draw the panels exactly to the correct shape. Then I just printed them out superimposed on each other on 30in x 112in paper. Here is a pic of the sail pattern with one of the sail panels lying on top of it to make sure that it matches. It matches perfectly of course.

Here are the coordinates of that sail panel and the resulting CAD drawing. Confused? If so, don't feel bad, it took me awhile to figure out what these coordinates meant.

I figure I paid the design fee so the design is mine. When I make some replacement sails in like 10 years, I'll just have to buy the materials.

You can't call me a sail maker since I'm clueless about sail design, but I guess you can call me a "sail assembler", kinda like the Chinese workers that most sail lofts outsource to nowadays.

Bow Eye and Trailer Adjustment

I installed the bow eye into the stem of the boat. The bow eye is just a long stainless u-bolt that the trailer winch attaches to. I had to chisel out some of the stem because the u-bolt wasn't long enough (this is a common practice I hear). On the back side of the u-bolt there is a steel backing plate to prevent the stem from getting crushed when the nuts are tightened. I also installed a metal clip where a pulley will be attached that rotates (or raises and lowers) the centerplate. I fabricated the metal clip out of some stainless steel plate using an angle grinder.

The boat saw a brief glimpse of daylight as I opened the garage door to winch it up on the trailer. Ooo ... here is a glimpse of the future towing rig. I know I know, it's a beast.

Back in the garage she goes. The garage door is sealed up with plastic again since its still pretty cold outside.

After a few hours of adjusting the roller and bunk heights, the boat is now firmly seated on the trailer. I moved the bow stop (and thus the boat) aft a foot or so to reduce the tongue weight. The boat and trailer will weigh about 1000lbs and I'm shooting for a tongue weight of about 50-70 lbs. After I moved the boat aft, the tilting function of the trailer actually wants to tilt the boat back even when the boat is all the way forward against the bow stop. I thought this would be a problem, but its actually not, because the winch pulls the boat forward and down, which automatically levels the trailer when I'm winching it up onto the trailer. Also, the tilt joint is locked in place with a pin except when launching the boat.

There was a scary moment when I tried to board her from the rear (gigidy) and the whole trailer and boat violently tipped back. After that, I added jack stands under the rear of the trailer frame. The boat is now stable enough for me to climb around in.