Monday, 22 August 2011

Illusion Hull for sale

Due to lack of space imposed by SWMBO my Illusion hull drew the short straw and has to go unfortunately.

So if anyone is interested in the bare hull let me know - either by a comment or a direct email.

She is not finished, so you have plenty of options for the seating, stowage and a mini-cabin.


Monday, 30 May 2011

Testing the tent

Illusion's tent uses material reclaimed from a discarded frame tent. Here it is well and truly tested by the English summer weather.

There is plenty of room but the eagled eyed amongst you will have spotted the fatal law - zips are not waterproof! So whilst its very convenient that, by pure chance, the original curved door is on top for easy won't be much fun waking up in a puddle:

A little water has run down the mast but the big puddle is due to the zip leaking, proven with a garden watering can. Plan B now.....time for a cuppa.

Hull Decking

Its been a while since I updated the blog - I tend to use the HBBR forum more (see

So here is a video of the decking which improves her dramatically. The only issue now is to keep the rain out! (more later):

Sunday, 17 October 2010

Design plans for Illusion

Illusion was designed with the simple to use Careene 2008 software written by Robert LainĂ©
Robert has kindly made the software available for download at the bottom of this page.

The program works in metric (mm) only - I would advise Americans to have a go at metric because the maths is much easier. Like most British people in their 50s I have used inches and mm since junior school. My feeling is that mm are more accurate for boat building. With care you can measure and cut to 1 mm, but measuring 1/32nd inch is hard and 1/16th is too crude - 1 mm fits nicely in between at about 1/25th inch.

So if you want the plans/offsets for Illusion download Carene, create a hull and enter these (metric) values for the bottom plank. She will be just over 3m or 10 feet, maximum beam is 39in as per Elusion:

Height forward and aft define the rocker, half width afterward is for the transom.

When you have pressed Validation, move onto these settings for the side planks:

You can now fine tune the design to suit your needs and the Hydrostatic page is great for seeing how she lies with additional ballast. Quickly you will realise that most of the weight should go forward, which is the biggest challenge I think.

File | Save | Development XYZ  will print out the curve offsets for each panel. 

Making the bottom panels from one piece of 9mm ply is tricky. She is mostly flat bottomed so it makes sense to keep one piece. But it is essential to make a saw-cut along the centreline about 2ft back from the bow to bend the V angle at the bow - without that saw-cut bending 9mm ply is impossible
So you have to bodge/adjust the design as you build it, which is part of the fun. If bending the bow V is hard, make the saw cut a few inches longer.

I was unable to fold the full V angle of 35 degrees so the bottom panel over hang the side panels by about 15mm. No worries I simply planed the overhang after the internal fillets hardened.

I trimmed the freeboard by 2-3in when the panels were stitched so the above dimensions are not 100% correct for Illusion. You have to make a choice between windage and sea-worthy qualities - there are good arguments for and against freeboard.

Rocker wise Illusion will sit with bow and stern on the waterline with a total displacement of 250kg. In hindsight I won't be getting near that displacement in sheltered waters, but from the videos on this site you will see she sails very well with 100kg displacement.  (100kg = 220lbs)

Saturday, 9 October 2010

Jim Michalak on Leeboards

An interesting short article on leeboards by Jim Michalak is here: Issues

Comparing pictures of Illusion I think my temporary lee board was about right; mounted parallel to the fore-aft axis and the area looks similar to Jim's Slam Dink design on his site. That might explain why the first sail was so successful.

Copyright Jim Michalak

This picture is my first guess at a suitable leeboard:

Wednesday, 6 October 2010

Desert Island Discs

Since time began BBC Radio 4 have a weekly show where celebrities chose just 10 tracks they could have if washed up (Lost?) on a deserted island. People often choose tracks that bring back memories and its a lot harder than you think to pick just 10 tracks.

For a musical diversion from boating I'm building my list of 10 tracks here.

  1. As a kid aged 6 in 1965 we only had five 45 rpm records to play on our record player. The rumour was that every record player in the UK had a copy of this record. What a cracker it is, the simple lyrics are timeless.

  2. My Dad was very handy with electrical and mechanical things and had a job in the late 60s changing the records every 2 weeks on jukeboxes in pubs and cafes. One Saturday he took me for a ride to a cafe and picked this song for me. He said people liked it because it was a bit longer than most songs, so they got more for their money (1s then or 5p in new money)

    I vividly remember hearing the song and liked it instantly. Here is a modern live version:

  3. I was one of those annoying kids that played a record over and over and over and over again. This one especially because of the hypnotic rhythm - it was a hit single in the UK.

  4. Around about 1973 I was at school friend's house. We played a few pop songs on his record player..then he asked if I had heard of this song. I said "No, what is it like?"

    He played it and today I can remember just how I felt 37 years ago. I was so amazed and had never heard music like that ever before. It was so different to pop music I had listened to on the radio or TV. At the end of the song I could hardly believe my ears and got him to play it again. I can vividly picture myself in his parents lounge standing over the radiogram near a window overlooking the back garden. Where did this music come from? Who on earth is the band? It was an amazing sound.

    So 18 years later, there I am with some mates in Arizona messing around in an amateur band in the drummer's front room trying to play this song (badly). Me on guitar and along comes the solo...ahh I don't know it. But in true rock and roll style I did the first 3 notes then winged it, playing as fast and wild as key, out of key..who cares. When we played back the cassette it was surprisingly good, shame we lost the tape.
    Rock and Roll...I love it.

  5. I went to this actual concert in 1975 with some school mates. Due to the beer consumed my memory of the night is a little fuzzy. Hard core fans will know that Jimmy Page broke a finger in his left hand 2 weeks before this concert but in true Rock God style he worked out a way of playing - you can hear a simpler guitar part compared to the album version.

  6. This song just floats along with a haunting memory. Its probably in my top 5.

  7. In 1977 I went to Uni, Freshers week was fun and in a disco I won a free T-Shirt because I knew exactly when this song was released (1971). It's a classic and was guaranteed to fill the floor back then.

  8. A massive one hit wonder in 1977, often played twice at Uni discos that year. Over 8 million hits on You Tube and still popular today.

  9. "And I was thinking to myself...." what were they smoking when they wrote this?

Thursday, 23 September 2010

A design similar to Illusion

I have been discussing other mini-Paradox designs with Paul Raymond who sent me his design based upon Matt Layden's design for Around In Ten design. There is more rocker than Illusion, obviously Matt designed this model as heavy displacement for rough seas, capable of carrying supplies for an extended voyage.

Paul tried using Carene 2008 but could not get a variable flare angle on the sides. He created this model in Rhino (a CAD modeller) and may transfer it to FreeShip.

If you have visited the Around In Ten site you may be thinking that since Illusion is 10ft long I might go completely nuts and try to sail her around the World. I may have a few crazy ideas, but I'm not a nutter with a death wish. A trip down the river with my HBBR friends is far more enjoyable!