Construction        

Sailing

Mods

Criteria:

  1. Light enough to car top, rig, sail and right alone.

  2. Cheap - preferably < 2 sheets plywood.

  3. Pack up small enough not to swamp me in my cramped garage.

  4. Platform to mess around with Atlantic and Oceanic configurations.

Design:

I designed the hull using Hulls by Gregg Carlson (http://www.carlsondesign.com). Simple but effective piece of software that allows you to develop a hull shape, and output the flattened panel shapes in DXF format. I used IMSI TurboCad 2D (2D is freeware) to lay up the 4x8 plywood sheet.

Here are some of my reasoning for the design:

14ft:  < 2 ply sheets, can fit in my garage, and fine to car top, and can move around by myself. 16ft would probably have been OK too, but just started to seem too big.

The displacement will probably be around 230lb for one person and 350lb for 2 people - 

950lb bouyancy? I was considering a narrower, lower hull, fully sealed deck (like a cat hull) but that wouldn't paddle very nicely, which I want to be able to do as well while Amanda has a bad leg. Fully decked would also require that I knew how I was going to rig it beforehand, which I don't. This is a compromise between a sailing canoe (which are either boring with not enough sail, or too exciting with too much) and a proper sailing proa, I guess.  In fact the hull is kind of like a deep pirogue.

Flat bottom = just adds some width to increase buoyancy without increasing draft or wood usage - this means less wetted area, therefore less friction at the cost of windward performance. Also adds stiffness, I imagine. More  comfortable to sit in when paddling. Deep V because I don't want to bother with any foils at the cost of wetted surface.

Rocker - I read somewhere that the vertical "dead wood" in the bow or stern just adds friction, but doesn't add WL. I flatter guess it would make beating more comfortable, and make the boat track better.

Flare in the bows: That would require another chine. Pitchpoling is less of a problem with a low aspect ratio rig, like the crab claw.

Stiffness: I haven't really decided about this yet - I'm going to have a 1 1/2 gunwhale of the same 1/4 ply, and a 3' deck on each end ( which I will probably seal off with a bulkhead for safety) Then a couple of seats, which will  also add stiffness.

Plywood - 1/4 inch luaun. It's got a few voids in it, but since the hull isn't too tortured I'm hoping it'll be OK. I'm not going to try to get to hawaii on this.... 

Epoxy seal - some bloke on the web wrote: "I don't glue with paint, and I don't paint with glue" I don't think I'm going to seal it since it's not going to live in the water. Primer and latex house paint should do the trick, according to the same guy.

Build Log:

Saturday 16th Feb 2002 - 3 Hours

Cut the 2 chines, keel and 1.5' inwhale sections from 2 4x8 ply boards. Started raining so I had to find some room inside to join the chine sections with butt blocks. Not enough room to butt the keel section. Went wine tasting with Amanda, Mark and Maryse. 

Sunday 17 Feb. 2002 - 4 hours.

Assembled the chines and keel. Found that this was going to be too hard to hold in place using duct tape, so I drilled holes at about 18' spacing along keel/chine joint, and stitched with cable ties. Cut stem and transom from scrap 1/2' ply, and stitched them to chines. Should have shaped these pieces, as it caused me trouble later. Mixed epoxy, painted around seams - mixed remaining epoxy with cabosil until it had a peanut butter consistency, and applied as fillets, shaping with a spreader cut to shape. Way to little epoxy, so had to mix more. Still not enough, so I made the fillets too small. Mixed more epoxy, layed 4" fiberglass tape in place, and spread epoxy over it. Fiberglassing into the corners of the stem and transom was tricky and left me with big folds in the fiberglass. Left to cure over night.

Monday 18 Feb - Presidents day - 4 hours.

Turned hull over. Sanded seams to give about a 1cm radius curve. Mixed epoxy, painted around seams. Mixed some with cabosill to make paste to fill voids. Soaked the correct length of FG tape in remainder of epoxy. Unrolled the soaded tape into place - this worked a lot better than soaking it in place as I had done on the other side.

Tues 19 Feb: 1 1/2 Hours

Cut as much of the messy unlaminated parts inside at the stem and transom. Applied a layer of neater FG from keel to bow, stern.

Wednesday 20 February  Before work: 1/2 hour

Tried to fill void behind newly applied tape with epoxy, but most of it ran out. Scraped up excess after work, which was still tacky.

Thursday 21 February : 2 1/2 hours.

Cut the breasthooks from scrap 1/2 plywood. Cut inwhales to shape to join with breasthooks at bow/stern. Cut 20 2' lengths of 2 1/2" PVC pipe for clamps. Mixed epoxy, painted chines and inwhales, mixed in some cabosil and applied to chine. Clamped losely in place, fitted breasthook and snugged up - clamped inwhales fully. Bow/Stern FG with cabosil thickened epoxy in an attempt to seal so that I can fill this void with epoxy tomorrow.

 

Friday 23 February: Nothing, went out in SF.

Saturday 24 February:  5 hours

Cut and installed bulkheads. I decided not to do stern/bow the same for some unknown reason, one is slightly bigger. Filleted and glassed in place with 2" FG. Filled stem, transom voids with cabosil thickened epoxy.

Sunday 25 February: 4 Hours. 

Sanded and painted sealed off area. Cut an oversize piece of 1/8" for decking.

Monday 26 February:5 Hours:

Made AKA by laminating 5" X 8' strips of 3/8 ply. Will cut in half for two beams. Spacers add stiffness. Could have been wider, probably 3 1/2" instead of 2 1/2. Glassed Stem/Transom and outside of middle seam.

Tuesday 27 February: 1/2 Hour 

Cut AKA's into two. 

Thursday  28 February:2 hours.

Epoxied: 

  1. Chair - still need stiffness in rest of boat.
  2. AKA supports.
  3. Support for deck in fordeck area. 
  4. Hatch covers.

Friday 1st March:  Nothing

Saturday 2nd March

Sanded and painted hull with primer.

Sunday 3 March:2 hours.

2 coats paint outside hull & inside hatchs. Varnished Oar and akas.Drilled holes in bow/stern for grips/ rigging attachments. Still need to seal some how. bought 10'X6" schedule 40 PVC pipe for the AMA. 

Monday 4 March: Before work 20 mins.

Another coat on hull and akas. Varnished outside covers.

After work:

Painted inside with primer. Another coat on akas, hatch covers. Drilled holes for aka lashing.

Tuesday 5 March :before Work: 30mins

Coat varnish akas. Fitted another support for deck.

Wednesday 6 March: 2hours

Fitted the decks. Sealed through the hull holes.

Thurs 7 March: 

More painting.

Saturday 9 March:4 hours.

Helped Mark move. Sealed hatches, epoxy sealed masts. Cut and joined sail. Sewed trampolines.

Sunday: 10 March

Finished the sail with grommets etc. Finished rigging the boat. Then went sailing for the first time.