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Building Tips

2006/12/19




Anchor
Bob and Sheila made a small sprit with roller for the anchor aft . This has worked out well and they deploy all Loose Moose 2's ground tackle from the well.

Leyenda uses an 35 lbs CQR with 15m 5/16" chain and 100m 1/2" Nylon cable.

Ballast
Mat laid 600 lbs lead  + 110 lbs  cement (vol.est.@96lbs/cu.ft.) each side in ballast boxes. A further 50 lbs lead each side was laid in the bilge under sole abaft bulkhead E to help trim her level only slightly down by head.

Dan writes: The hull underneath the ballast should be through bolted to every frame member surrounding the ballast and the ballast should be supported by rods or bolts through the frames. The corners where the bottom meets the bilge board cases should be heavily fiber glassed. 

Dave and Anke screw copper sheets to the bottom of their Luna and that way solve the anti fouling problem too. They use bronze screws to avoid electrolysis. Today (2006) they say that water probably penerated through the tar sealed holes into the bottom planking, as the boat had become quite heavy by the time.

Bilge boards
If you opt for all wooden boards instead of the alloy core, be sure to put a metal sleeve inside the boards so that the pin is not bearing on wood.

Bright work
Tim did send an e-mail from Australia:
One word from my own current bitter experience: ensure the interior surfaces of panels, stringers, beams etc. are all smooth finished (i.e. final sanded ready for painting or varnishing) before actually fitting them; also make =sure= you rapidly clean up glue runs and so on. It's impossible (and a danger to health) to clean up properly once the boat is all together, as I've just found. I've given up trying to get a yacht-like interior to Lady Kate, we're now just going to paint with latex paint. The detail of finish (from professional builders no less) is so bad that we can't use gloss paint because it will show all the mess. Problem is that the interior is intricate once fully together and sanding all the mooks and crannies just can't be done (well, it can be, but only at a horrendous time cost)

Copperpoxy
Applying is in 2 stages: first layer with a foam roller. That results in an surface like coarse sandpaper. Object here is to establish film thickness. Second layer with a squeegee to fill the valleys between the peaks. The need to sand depends on your squeegee skills. Stirring of the material by hand can be a bit of a hassle especially at a low temperature, but warming on my wood stove did help.

Lady Kate was finished below the waterline in copperpoxy (local equivalent, different trade name), bilge boards too. It's still working well after 5 years BUT Lady Kate lives in fresh water.

Have in mind, you can't clean a flat bottom easily at low tide. A friend of mine (scuba diver) offered to clean Twilight's bottom once a year...

Fiberglass AS29
Bruce made a table covered with Formica and laid up the bottom and sides out of  four layers of biaxial cloth and vinyl ester resin. The bottom was than placed in a particle board cradle, plywood bulkheads were bonded to it and the sides bonded to the bottom and bulkheads. The top is from a mold for a Mirage 34, the cockpit from a 24' racing boat. The stern is stepped to facilitate getting out of the water and the bow is brought to a point. Bruce used an offset centerboard in place of the bilge boards, this in addition to moving the forward berths forward gave him room for a shower with standing headroom on the starboard side.

Insulation
Discussing with Dave a sandwiched deck with a foam core or vertical plywood stripes as mentioned by the Gougeon Brothers  he answered:
I'd thought more along the lines of a standard Bolger deck (longitudinal deck stringers supporting the ply deck), but with a second, lighter deck screwed into the stringers from the underside, with panels of foam loose (not glued, that is) and held in place between the true deck and false one. This wouldn't be nearly as strong as the Gougeon system, but easier to build, stronger than designed, and everything could be dissassembled, cleaned and inspected. Unfortunately, I thunk of it too late for LUNA.

Kevils
The kevils are too short for two thick dock lines. Make them at least two inches longer on the outside, says Dan.

Limber holes
If one would build bulkhead G to plan the condensation water would drain right into the double bunk... I asked Tim how the problem is solved at his boat. His answer:
The limber hole isn't there. In fact ...none of the limberholes shown in bulkheads on the plans are present on Lady Kate. This is a design modification I approve of! - apart from preventing wet bedding, you want the ability to watertight-seal compartments if voyaging. The limber hole in bulkhead G particularly needs to be stopped up- think in terms of a following wave filling the mizzen/engine void and entering through the dorade vent: better to have the flow in your drawers rather than right through the boat....

Noise
Tim writes:
Anchor: very noisy. Solution is to go to the other side of the channel/island/harbour where there aren't waves. Berthed/anchored, with ripples: the stern is quite noisy too from the slap-slap of wavelets and ripples. Deborah and I quite like the noise, which is natural, soothing and masks other noises.

The bow sometimes  slams, sending a shudder throughout the hull, especially when fishing trawlers motor past at night says Mat. In heavy chop and strong winds he reduces the noise by tying a spring warp to the anchor chain/ rope shackle and allowing the boat to lie broadside to the wind on a bridle setup by cleating off the spring to the mizzen cleat. (motion is a bit jerky...)
A solution in lesser winds and chop is to inflate a cheap rubberized nylon surf mat (5' x 2'6"). The trick is to inflate to only about 2/3 pressure and tie it back aft and underwater a bit to overlap the water/hull bottom interface. Mat uses 2 lines tied back to the spinnaker sheet blocks.

Plywood
I use mostly birch plywood from Finland well coated with epoxy, on deck the lighter Bruynzeel's Okumé and some inexpensive Lauan ply in minor interior places.
As Bernie Wolfart suggested some years ago we tested our Finply by making a cutting board for the kitchen from a piece of scrap and placed it into the dishwasher every couple of days.
You´ll have to replace your old plastic cutting board anyway...  needed for rudder bearings!

Ports
For strength, the port lights on the hull should be on the outside.

Post in the main saloon
Needed to support the deck, says Dan. Handy to support a table and give hand holds.

Tim wrote: We cut out the post in the main saloon of Lady Kate once we had built the the galley back to plan, including the dresser. The dresser and associated bulkhead were important structural members. The fore deck is slightly springy, but what I think we'll end up doing is putting in a laminated crossbeam rather than reverting to a post. Mind you, if we were Southern Oceaning, I'd probably have two posts in the main saloon!

Rub Rails
Because the sides are vertical, make rub rails bigger and make one lower to protect against projections on pilings near the waterline. (Dan)

Rudder
The rudder post of Lady Kate is run through plastic bearings made out of ordinary vegetable chopping boards (white, very slippery) gives a self lubricating bearing.

Side panels (lower)
Dave writes: ... we punched a hole in our Long Micro at the waterline (in order to save 3 miles they took a shortcut and had an unpleasant encounter with a short branch spike of a log in front of a bank of sand...), and decided to run a second layer of plywood along the hull to a point about 5cm above where bottom meets transoms.  This doubles the hull thickness to about 20cm above the waterline Additionally, we used it in the big boat (Luna) at construction time as the horizontal butt block between upper and lower side panels, and it worked great!

Timber
In order to contribute to save the rain forests I opted for local species: mostly larch, black locust for bottom frames, bow and transom, ash for interior framing in few places where hardwood seems appropriate.

Water Tanks
Dan has two flexible bladder tanks 26 gallons each, in the place shown for the middle drawers under the main saloon settees.

 




© 1999-2006 by L. W. Foltz

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