Sunday 31 March 2013

Building a 1/5th Model with DelftShip

I tried my hand at building some models for some of the previous designs I considered and found it a very useful exercise.  For John Welsford's Pathfinder I built both a 1/10th model and a 1/5th model.  I didn't go very far with the 1/10th model because once I had done the moulds I pretty soon realised that it wasn't going to give me what I wanted without major hull design changes.  This got me into using CAD software for developing the 1/5th Model specs.  I got into using the free version of DelftShip which was extremely beneficial and I can highly recommend it. It takes a bit of figuring out but once you are familiar with it, it is a real time saver.  I used it to develop the plank edge profiles and moulds for Skye Maid.  These aren't provided with Kees plans at this stage but my starting point was Iain Oughtred's full size mould drawings which are a very good starting point.

Here's a screen shot from DelfShip hull profile of Skye Maid:

 I purchased a full licence for DelfShip which gives the capability to print our plank patterns - another time saver.



 

"Skye Maid" begins

Begin with the end in mind say motivational experts! There's nothing like looking at drawings of the finished boat to strir the body into boat building action.  Above is a pic of Kees Prins drawing for my Fulmar cruising conversion with the sail plan and hull expansion I specified.  The boat dimensions (for this design is named named "Far Fetch" by Kees - i.e. taking his own design a little further) are as follows:

Lenght Overall (LOA) excluding bow sprit - 16ft 9inches - 5.10m
Lenght on Waterline (DWL) - 16ft 1 inch  - 4.90m
Beam - 6ft 4.5inches - 1.94m
Draft - 13.5inches/4 feet   -  0.34m/1.20m
Displacement 1900lbs  - 865kg
Ballast Keel Shoe - 230lbs  - 105kg
Boat Weight 1400lbs  - 640kg
Sail Area 150sq ft  - 14sq m

If you interested in building this design contact Kees Prins at keesprins@gmail.com  You will need to purchase Kees' construction plans as well as the original Iain Oughtred Fulmar plans.  You will find Iain's plans available on the web from a number of sources including Wooden Boat Magazine in the US and Jordan Boats in UK.  In Australia Iain Oughtred is represented by Robert Ayliffe of Straydogboatworks http://www.straydogboatworks.com/

For the moment the name I am giving to my boat is SKYE MAID.  This is both a tribute to outstanding  small boat design work of Iain Oughtred and reflects both his current home in the Isle of Skye and my Scottish heritage (one branch of my ancestors comes from the Isle of Skye where Iain now resides).  My previous boat, a Sunmaid 20 was named "Brigadoon".  





Saturday 30 March 2013

The Design Shortlist



Here's a brief overview of the "finalist" designs I really liked which you might call my shortlist for the main boat I will be building (more about this later).

1. (the late) Phil Bolger's Chebacco.  At 20 feet she's a bit bigger than what I really have capacity for building but I liked the look of her, her relatively lightweight and the neat positioning of rudder in front of motor and boxed keel.  Stories from builders were alluring. However cabin space was limited for a boat of this length.


2. Dudley Dix's Cape Cutter 19 has plenty of room and outboard in well. The cutter rig has a lot of appeal for me to maintain sailability in strong breeze and easily gearing up/down sail for single handing. However hull still just a little too big for my building space.

3. Pocket Ship (above) by John Harris is a very clever design in just 14 feet - I got very close to proceeding with this but couldn't quite come to grips with the sail plan  and windward ability , particularly if single handing in the strong sea breezes and southerly changes prominent around Sydney.

4. The above is Kees Prins cruising conversion of an Iain Oughtred Fulmar. This is basically the boat I am going to build - an Expanded Cruising Fulmar.  It is based on Iain Oughtred's Fulmar plans (which I already had). This design is the biggest of his family of three performance dayboats, Sheerwater, Gannet and Fulmar.  The picture above shows Kees Prins cruising cabin yawl version called Fetch. He converted this from an existing open Fulmar.  I have commissioned Kees to draw up construction plans (in consultation with Iain) for a slightly different version. Mine will be cutter rigged and wider towards the stern (using a "wedge" insert tapering from 10 inches at the stern to nil at the bow - an inspiration of my brother David Gregor an aircraft engineer and experienced sailor) with raised sheerline (4 inches at stern, 3 inches midships and 2 inches at bow).  She will be just under 17 feet. Iain Oughtred's hull and sailplan design give a slick performer which impressed me greatly in pics and videos. She is similar in size and design to the Wayfarer - a mainstay of UK Dinghy Cruising,  the most famous exponents of whom are Frank and Margaret Dye.


5. John Brooks version of the Herreshoff 12 1/2 (above) is a classic and beautiful day boat. I bought the plans for this and may still build it one day.  But Cruising Fulmar is more suitable for my current cruising needs.

6. The above is a John Welsford's 18 foot Pathfinder - big sister to 14 foot Navigator. I got close to proceeding with a sloop version of this but could not get comfortable cockpot space and cabin space without totally changing the design.

So there you have it - I am going to be building a  Cruising version of Iain Oughtred's Fulmar with assistance from Kees Prins.