Sunday, April 29, 2018

Vision Rowing Shells

In 2001 I was commissioned to design a competition rowing shell. The result was the Vision Single, which was built in Lightweight and Heavyweight versions. The builder was Slade Rowing, moulding the boats in female moulds from pre-preg carbon/epoxy with Nomex core. They were built in Johannesburg, South Africa, with the aim of selling into the international market.

The design that I drew broke with all of the traditions of rowing sculls in terms of hull shape. It was very advanced, with shape features not previously seen in rowing shells. Before designing it I told my client that I could draw a boat at least equal to the best but it would be difficult to sell to the traditional rowing community because it would be so very different.

The boats were very fast but, before they could be proven in top level competition, Slade Rowing failed under the weight of logistical problems that overwhelmed the company due to limited funding.
Vision Lightweight Single scull as built by Slade Rowing.
This design has lain almost unused since the closure of Slade Rowing. Now it is attracting interest again. A new Vision Single was launched in New South Wales, Australia, a few weeks ago and has been going through testing, with a second boat to follow. The two amateur builders have reported that their new boat has lived up to all of their hopes and is now ready to begin competition.

An amateur-built pre-preg carbon/epoxy/Nomex boat? No. They have built their boat from strip timber, with a layer of glass on the outside. The first boat was a learning experience and the lessons learned in that first build will be applied to the second build, modifying some details and techniques to improve the result in all respects.

Peter Bowman initiated the project. He was researching rowing shells on-line for a self-build and came across my Vision Single web page. He appreciated that this 17-year old design has advanced features, some of which are now appearing on boats built by the big-name builders. He asked me if it can be built from wood. I had construction drawings available but they were detailed more for recreational rowing than racing in a highly competitive fleet.

Peter teamed up with a friend from the rowing club, Owen Redhead, a tech science teacher. With Owen's expertise, the two felt capable of building the Vision Lightweight Single in strip plank using the low density hardwood paulownia. At 280kg/m^3, straight-grained, easily-worked and gluing well, paulownia is a good choice for boatbuilding when light weight is a requirement.
Vision Lightweight Single paulownia hull with deck and cockpit being fitted. Alongside is the frame over which the hull skin was constructed.
The new wooden boat, ready for launch.
Reports of the characteristics of the new boat on the water confirm those reported by Paul Slade. This is a boat that is fast, pitches very little through the rowing cycle, tracks well and carries its speed better than most through the recovery phase.

Vision Single being rowed by Rohan Hislop.
The first boat is a few kg over target weight but there are known areas where it was over-built, where weight can be trimmed out to get the next one closer to target.

This design is not on our pricelist. Email me if you would like to discuss buying plans for it. To see our full range of designs go to our main website or our mobile website.

Tuesday, April 17, 2018

DH550 Charter Catamaran

The DH550 catamaran has been or is being built in the Caribbean, Europe, Africa and Australia. All of these builds have been to the original design, as drawn for Phil and Laura Harvey to build the prototype "Wild Vanilla" as a family cruiser.
"Wild Vanilla", now renamed "Taika" under her new owner
We now have a new version of the DH550 , named the DH550 Charter. It was commissioned by a charter company and construction will start in the next few weeks. It has features that are better suited to charter service, in the cabins, bridgedeck accommodations and rig.

This version has four equal double guest cabins, each with en-suite heads and shower. There is also a compact single crew cabin in the bows of each hull and a shared crew heads with shower in the starboard hull.

More space has been given over to life outside, so the bridgedeck accommodation has a smaller saloon and larger cockpit than the cruising version. It has two galleys, one internal and the other in the cockpit. The forward cockpit, a working area in the cruising version, is changed to a social area with seating and folding table. The working cockpit has moved aft to above the outside galley, with helm and engine controls. All sail control lines, except halliard and reefing lines, are led to a pair of electric winches mounted on the cabin roof. This cockpit has large cave lockers to keep the ropes tidy and out from underfoot.
DH550 Charter accommodation
The rig commissioned by my client has in-mast furling for easy handling. It has vertical battens to support modest roach.The boom has been raised for better clearance over the working cockpit. It has also been lengthened to regain some of the lost sail area and to move the sheet further aft to where it won't conflict with the working cockpit. A pair of posts has been added in the cockpit to pick up the loads applied to the cockpit roof by the mainsheet.
DH550 Charter rig with in-mast furling and vertical battens.
I also drew an alternative charter rig with slab reefing instead of in-mast furling. It regains area by means of more roach

Aesthetically, the charter and cruising versions are little different. The working cockpit is fairly inconspicuous, so doesn't spoil the clean lines of the cabin.

This version is only offered with cruising keels, for simplicity of operation. Lack of the daggerboard casings also gives more freedom for fitting in the required accommodation in the forward guest cabins.

The two steering stations are separate, connected only at the tillers on the rudder shafts, giving 100% redundancy. In the event of breaking a steering cable, the boat can still be steered at the other helm.

To see more of this and our other designs, go to our main website or our mobile website.

Monday, April 16, 2018

Glassing the Sportfisherman

Glassing of Kevin Agee's 26ft sportfisherman started yesterday, using WEST epoxy with a slow hardener to give ample time to do the work. We settled on a procedure that would give a surface that will need the least amount of fairing after completion of the glassing. That needed the glass fabric, 1708 biaxial glass with chopped strand mat on one side, to be laid down in a single length to eliminate transverse laps.

The procedure was to set up the roll of glass on a stand in front of the hull, then roll it out onto the bottom of the hull, cutting to size and shape. The 50" roll width was enough to cover one side from alongside the keel runner across to the chine, including the overlap onto the side. We cut two of these, one for each side, then rolled them up, ready for use.
Glass fabric laid out on hull and cut to shape.
The glass layer was to be covered by a layer of peel ply, so the order of tasks was to pre-coat the wood with epoxy in increments of approx 4ft, roll out the glass, wet-out the fabric with epoxy applied with mohair rollers, roll out the bubbles with ribbed rollers, lay peel ply over the top, squeegee smooth, then move on to the next 4ft section and repeat the process. The peel ply we laid in transverse strips so that we wouldn't be working with two rolls one behind the other to complicate the process.

Michelle mixed the epoxy, Kevin worked from the side on a ladder and I worked on top from the other side of centreline. We worked from transom through to the bow. About half-way through we realised that the planned completion of both sides of the bottom was not going to work. How was I going to work on top of the hull with fresh laminate where I had to stand? So the plan changed from doing two bottom panels in the day to doing one bottom panel and the opposite side, to remove any conflicts.
Half bottom glassed and covered with peel ply.
Glass wrapped onto transom. The glass roll on top of the engine bracket is for other bottom panel.
Two of Kevin's friends arrived to help after lunch, so we now had five working together to follow the same procedure. This was a big help because measuring out the glass for the side needed the glass to be held up against the hull, rather than calling on gravity to hold it there as we could with the bottom panel. The two new guys had done this work before, which none of the other three of us had done. They introduced the additional step of laying the glass back against the previous work to roll resin onto the contact surface of the new glass before it is pressed against the resin on the plywood, speeding up the wetting process.
Hull side glassed and covered with peel ply. It wraps across the chine flat and onto the bottom. When the second bottom is glassed there will be a double layer over the chine, a high-abrasion area that needs greater protection.
Side laminate wrapped onto transom. 
Other work that was done prior to starting the glassing was gluing the bottom panels onto the engine bracket, as well as structural epoxy fillets around the perimeter and inside the bracket. Some of this can be seen in the photo above.

The rest of the hull will be glassed over the next week.

This design is still not on our website, so there are no links to the design in this post. To see our range of designs go to our desktop website or our mobile website.

Wednesday, April 11, 2018

Cape Cutter 19 Developments

Following on my post of a few weeks ago with Cape Cutter 19 News, I have some more developments to report.

First is the CNC plywood kit. Years ago two plywood kits were cut by CKD Boats in Cape Town before the moulds for the GRP boats were sold to Honnor Marine, who rescinded the rights to cut kits. Now, with the moulds and GRP production under new ownership of Cape Cutter Marine, we are once again able to sell CNC plywood kits. I completed the new files, with jigsaw joints to all components that are too large for one sheet of plywood. The kit comprises bulkheads, centreplate casing and skin panels for hull, deck and cockpit. We will be able to supply kits in USA and they will also be available from our normal kit suppliers in various countries. Email me for more info.
Cape Cutter 19 being built from one of the two kits cut years ago. The new kits will be similar quality but with jigsaw joints to larger panels.
The other development with the Cape Cutter 19 is under the water. We have had a bilge keel (twin keel) option for the Cape Henry 21 for a few years. The first was launched in Cape Town in 2012. Sailing reports have been of good speed and handling characteristics, with the owner very happy with his boat and other observers impressed with her speed. There is not a similar boat with centreplate nearby to allow comparative sailing to tell us the differences but that will happen sometime in the future, when the opportunity arises.
Cape Henry 21 with bilge keels, being launched in Cape Town, South Africa.
We have not had the bilge keel option for the Cape Cutter 19. A few people have asked when we will have this option and it has now happened. Today I have completed the drawings and will add it to our pricelist in the next few days. The first boat with this option will be built by an amateur builder in the Philippines. This version is able to dry out on shallow moorings, standing upright on the twin keels and skeg.

To see our full range of designs, go to our main website or our mobile website.


Monday, April 9, 2018

26ft Sportfisherman - Working Both Ends

The longboard sanding of Kevin Agee's boat is done. The hull is as near to fair as it needs to be at this stage. Still to come is the glassing, followed by sprayed fairing compound and final fairing.

I completed the shaping of the stem capping. This involved planing and sanding it flush with the hull skin then rounding off the tip to a radius suitable for the fibreglass cloth to wrap around. Also fairing it smoothly into the front end of the keel runner.

The hull is looking very nice, with fair curves to the profile and chine edges. Any bumps and dips in those edges will catch the eye, so it is worthwhile to take care with smoothing them out before any glassing is done.
Stem capping shaped flush with the hull skin and rounded off to a neat radius.
Fair curves
Fairing of stem capping into keel runner completed.
The other work going on is building the bracket that will support the outboard engine/s. Previous posts have shown how the fore/aft gussets pass through the transom and bond onto the girders inside the hull. Now the laminated plywood engine board has been built and glued onto those gussets. Before doing this the gussets were checked for alignment relative to each other and the transom, with some minor trimming to true them up.
Completed engine board. This is the aft face. The stepped bottom edge matches the angle on the boat and will be planed smooth before the bottom skin is glued on.
Front face of the engine board, slotted for the gussets that will connect it to the transom.
Engine board glued onto the gussets.

Test-fitting the bottom plywood onto the engine bracket.
Glassing the hull will be starting soon and in a few weeks the hull will be ready to be turned over. Follow progress in future posts.

This design has not been completed yet, so is not on our website. I hope to have it available in a few months.

See our range of designs on our main website or our mobile website.

Tuesday, April 3, 2018

Sandy Point Yacht Club Easter Regatta

Sandy Point Yacht Club in Langebaan, South Africa, is a rather informal group of like-minded people, led by Commodore Bruce Tedder. Langebaan is a holiday community about 60 miles north of Cape Town. The Langebaaan lagoon is one of a very small number of lagoons that can provide shelter to ocean sailors around the coasts of South Africa. It also provides excellent small boat sailing on flat water, with sometimes very strong winds (and very chilly water). The "like mind" of the club members is a love for sailing classically-styled small boats.

One of my designs, the Sentinel Explorer 18, has attracted a strong following in the Langebaan area. The Explorer is a GRP Lapstrake design, full-bodied to carry a good load as a family fun boat. With a gunter rig that has fairly modest proportions by my normal standards, this boat has proven itself to be ideal for safe sailing in the sometimes robust conditions of the area.

Sandy Point Yacht Club hosts a regatta every Easter weekend. The core of the fleet has been the local Explorers but the reputation of fun casual racing has attracted an expanding range of small boats to the event. The photos that I am showing here are of some of the Explorers racing. I also see two of the smaller sisters, the Sentinel Challenger, in some of the photos.











My thanks to photographer Kerryn Arthur for making them available for my use.