Thursday, June 30, 2016

Header Photo: The Dabchick Scow - One of those Sit-on-Top Dinghies

The previous header photo was of South African Jack Koper's Dabchick scow, a junior trainer that was Koper's first design, done in 1955. Designed as a simple home-build project, the Dabchick still remains a popular junior trainer in South Africa. It is somewhat unique among current singlehanders, being a sit-on-top design (no cockpit) and having a sloop rig instead of the normal cat rig. Jack Koper's two other scow designs have been profiled in previous Earwigoagin posts and his two man Sonnet scow also has a sizeable following in South Africa.

Modern research tells us that flat leg hiking is supposedly the most ergonomic way to hike. There is no other way to hike but to hike with flat legs in a Dabchick.

A modern racing glass Dabchick. Plenty of controls here for the dedicated junior competitor.

The Dabchick class has also bumped out the roach of the original mainsail and allowed mylar sail cloth. Joe over at the blog Horse's Mouth has also done an extended post on the Dabchick.

Which brings me to the rich and long history of the sit-on-top dinghy, a design feature(?) that was solely aimed at the home-builder - eliminating the cockpit made construction much simpler and made the hull a buoyant cork. (The trade-off was the disappearance of the comfort of a cockpit - sitting-on-top was definitely more precarious, more awash with the elements, more wearing on the sitz bone. The public usually went with a cockpit when given a choice.)

One of the early sit-on-tops was Crosby's Skimmer Moth designed in 1933, with plans published in The Rudder magazine. An example was recently uncovered by Yarrow Thorne in New England. I've always fancied this green for a deck color.

The Alcort Sailfish is the sit-on-top most of us North American oldsters have encountered at some point, either having the unique experience of whooshing around on one or coming upon one on the beach. Designed in 1945 by Al Bryan and Cortlandt Heyniger, the Sailfish was originally offered as plans but then shortly their company, Alcort, offered the Sailfish as a kit. It was the right boat at the right time as there was a big DIY boat building boom in the post war years. The Sailfish was eventually eclipsed by the bigger brother, the fiberglass Sunfish sporting a cockpit.

One of the sheet of plans for the Sailfish.


The history goes that English dinghy designer Ian Proctor was over for the 1958 America's Cup and was intrigued with the Alcort "beach boats" he saw sailing on the New England waters. He went back to England and designed his version of a sit-on-top, the flush decked Minisail Monaco scow, originally built in fiberglass. A plywood version, the Sprite scow, came out a short time later. The Minisail line grew, added cockpits and sliding seats and eventually continual development produced the well-known roto-molded Topper junior trainer (fun bit here and another fun bit here and the serious junior bit here).

Renowned dinghy designer Frank Bethwaite's first design, in 1962, was a sit-on-top scow junior trainer for his kids, the Northbridge Junior. His sit-on-top featured a dished concave deck, not a convex deck and was only 2.44 meters long (8 feet). This photo shows a modern build with modern mylar rig and carbon mast.

One sheet of the Northbridge Jr. plans that I found kicking about on the Internet.

A Northbridge Junior build in Japan.

There is also the Australian Sailfish scow sit-on-top.

Here is a PDF of Australian Sailfish plans.


Paul Mullings said...

I also recall the Toy, similar to the Minisail but much faster

Tweezerman said...

Ah!, the TOY - Tony Allen's Own Yacht, a singlehander with sliding seat designed for the IYRU trials that eventually selected the Contender. I also admired the TOY - never seen one in the flesh - but that bluff bow is an acquired taste, one that I like. However I wouldn't classify the TOY as a SOT (sit-on-top) dinghy but a SOS (sit-on-seat) dinghy (just like the International Canoe).

Unknown said...

Does anyone have knowledge or information about the Bethwaite design A12? I have a boat that I'm told is an example of this design, a Moth-like design but 12' in length, 4' wide. My sail No. is 14, I understand maybe 50 were built in Australia? It was set up as a single handed trapezing scow. I purchased it a few years back on ebay, came from canberra at the time, the owner knew nothing of it's design or provenance.

Tweezerman said...


Didn't know that Bethwaite had a larger scow than the Northbridge Junior scow. Maybe I'll do a short post to see if I get any response through this blog.

Stephen said...

My brother bought a Northbridge A12 in the 1970's. He sadly died last year but my sister in law still has it in pretty good nick given the age. It is a beautiful boat if not a bit heavy with a bethwaite like mast and blue sail. a real handful.

Scorpex said...

I definitely remember the A12 being advertised in Seacraft in the 70s. As a young Moth scow sailor, I wanted one.....but never saw one in the flesh, so to speak. Good to hear that there may be a few examples around.