Alternative to marvelous Buccaneer 24

Gary, I hate to hear of the damage-Da Ravens got a solution. I do too-round the rug rats up and make them sand carbon! And yes, James I am paying attention.....just don't quite understand.

 

"Well, it does STAND out," was one of the comments/criticisms I heard - so it's my fault. But the damage was minimal and quickly repaired. Have moved on.
The 11.5 metre wing weighs 56 kgs at this stage. Don't think I could have built it any lighter in (2.5mm) ply and Port Orford cedar. The trailing, larger area behind the long D will be skinned in epoxied 3 oz glass laid up on a painted/polished ply sheet for a table. Have done a small area as a test and the result is light, smooth and also stiff enough for the job.
In the old days when I built my first wing mast, (not full wing like Sid's) all the talk (mostly from Malcolm Tennant) was of thick sections and semi-circular leading edges for less stalling problems (meaning you can steer up or down over a broader range and still keep air flow attached) - but later masts I've built were proportionately thinner and with finer leading edge shapes - because I've never found the stalling problems that we were warned about. Also thinner, fine,r equals less drag, also less weight.
So Sid's nose is very fine and it is up to you to have eyes up and steering a fine course - because when everything is aligned correctly, you go very fast. I'm talking about wing mast/soft sail ... and presume the same thing applies with the asymmetrical full wing. But I know nothing, just following hunches and my nose.
Couldn't quite figure out your question about mast base template movement upwards, James - if you mean twist, I'm building two flaps off the wing's trailing edge so the upper one will be twisted off.
Here's an old cross section drawing of Flash Harry's wing mast (450 mm x 140mm, then Sid's full wing (1.50 m x 170mm thick - the flap (not shown) is 500mm x 50mm). Remember these are not to scale but the point is Harry's wing thickness is 140 and Sid's is 170mm.

 

James, that is a very tall mast for a B Class; Flash Harry's, which originally had a B Class rig from Boadacea, top B Class here before the Tornados arrived, was 30 foot or thereabouts. The original was ply and too heavy so I built another, same height but half the weight, approximately 30 lbs.
Interesting to see how Lock's team went about constructing a leading edge rig in those days. How heavy was it?

 

Spelling correction: Boadicea, designed and built by the McKinvens then when Boadicea destroyed herself in a cartwheel, was passed to Dave Tapper who put it on Demon Tricycle, and then when he changed rigs, shifted to me for F. Harry, and I think I must have broke it so built the lighter one ... which is now going onto a stripped out Piver Nugget.

 

'B' class wing-mast - construction, size, weight etc

G'day y'all - & to Doug & gary (sure hope Steve joins in with this)

Firstly - Thanks you Gary for being so - in-depth honest & sharing all this info with us.
2/ Please accept my severe dyslexia - so if I make a mistake - it's because that's the way it is.
3/ While I can measure in both metric & imperial - I need to think in imperial - it's an age thingo.

4/ Gary - if "But I know nothing, just following hunches & my nose" - nonsence, don't one word of the first part & all of the "following hunches & my nose".

Let's recap a tad: 'B' class cat, Crowther designed hulls, folding beams, large wing mast c/w soft sail aft 1/2 of sail area.
Wing was 39' ish high off the front alloy beam 10'6" back from the bow.
Wing was 14" thick @ 18" aft of leading edge.
Wing was 60" from leading edge to trailing edge where the soft sail fitted
into a sail track - recessed into the back of the foil. (seamless join)
Wing was still 48" x 9" thick @ the hounds - 25' off the deck.
Wing was 24" x 4" thick at the top & was very square toped.
Wing - main spar - very thin 5" alloy ag pipe - top 1/4 squashed to size.
Wing had 1/8" ply section frames @ 18" spacings held in place to the main
spar by small alloy 'L' shaped sections held in place by pop rivets.
(do remember this was 1/ in 1965 - 2/ the best practice back in those
days & 3/ importantly the pop rivets sheared & we took a huge step
forward - Gawd we were very lucky & ha ha - didn't notice it for quite
some time.

Wing had very thin Mylar wrapped around the leading edge - back to the max
thickness point @ 18" from the very front. As a sailing boat gets pulled
froward not pushed - then the wind will not have a tendency to - blow
the wing shape inwards - but in fact - do just the opposite - pull it out
& keep it in shape.
Wing was then completely covered with sail cloth - stuck-on only at the
trailing edge with the contact the aircraft industry uses to glue the
'heating rubbers' on the leading edge of aircraft in freezing climates.

***** Well - here we are again - (a day late & a $ short) so to speak. I didn't notice until just now that there was an 'edit' option available, so I'll try to pick-this-up where I dropped the ball.
I'll see sif I can pick-up the above threat where I lost it & keep-it in line. so that it all makes some sort of sense.

Wing surface covering was allowed to 'float' - where the wind pressure
exerted sufficient pressure to 'pull it out' !!! The 'wing' is not
compressed by the wind pressure - just as the sail boat is not pushed
to windward - it is pulled forward.
**This is very important to consider - as that realization effects the building, structure & thus the weight of the wing mast. IMHO

Wing foil bottom template (15" thick ply) broke loose from the mast (sheared
alloy pop rivets) & for some time floated up & down as the pressure of
the wind speed over the mast demanded.

Short story: While trying to retain the 'B' class Aust. champs the bottoim template started to move up & down several inches. Wind blowing a steady 15 to 20 kts - increased to 20 to 25 gusting to 30. Gosh that keeps you very busy, wet & tired. Gawd - what do we do now - Help. Wing-mast foil section is now concaving between templates - up to 6" thinner. Brian says - come back off the bow (now going down-wind & still in the lead) dry your bloody hands & light us a smoke - OK - out on trap wire - do what I'm told - look back & see that we've increased our lead considerably - Wow (everyone knows that a single rig can not possibly out-reach a sloop rig especially when it's a new Tornado - & 3 of them at that) OK - bottom mark - lead still growing - Jim harden-up quickly - Yes Sir - we'll try to run along the beach - without tacking - 3 ks later - throwing-off sheet - to bear-down to the mark - lead now becomming very large. Harden up to port & head for the finish line. YES YES Brian WOW There are some really big names behind us. Man - we've done it again, YES!
Brian - let's not change the bottom template, let's just see how it works next race. 4 Years later we were still watching the bottom template - do its thing & still winning races. Never finished behind a Tornado in all that time.

BUT then came the day (long weekend) that Linsay Cunningham & John Buzaglo came up to Sydney & won every race that whole weekend. 'B' class Quest - designed, built & sailed by Linsay himself. Geeeze did he ever give us a 'whumping' !! Out sailed us in ever condition - at every angle. Our 8 years old heavy hulls (repaired 7 times) & o;lder shape wing - just got sjhit-on by a better, lighter, stiffer boat. Linsay & Buzz were no mean sailors either.
The quest 'B' class cat was always lighter, stiffer & 10 to 15% faster than any Tornado ever built. It's a shame they closed the class development down cause there is/was a long way to go & always will be. don't shoot this messanger-boy - just ask Doug - hey!!

Back to wing; If the wing section automatically reacts to the wind pressure - that will always happen much faster than a persons late & slow response. by a very big margin.

Gary, I did re-check the mast height - was 39'6" above the cross-beam - cross-beam (4" dia alloy) mounted on top of hull-decks, 12" farther-back that all other 'B' class cats, Lock;ie's hulls were at least 5" higher at the front beam than anything around. VERY EASY TO FIND BOAT WHEN IN THE MIDDLE OF 20 OTHER 'B' CLASS CATS ON THE BEACH though.

The 'wing' foil shape started 26" off the deck.
The bottom template had a 5' alloy arm attached to it that had a 'noose' rope comming from the end to controll the angle between the wing & the mainsail.

The wing was some 260 sq ft of total surface area - divided by 2 = 130 sq ft out of 238 sq ft - which they are now saying (I thought it was 250 sq ft total). The 2 booms were only 5 sq ft.

The whole mast - incl short boom attached - 2 side stays (5/16 - 1x19) & the fore-stay - same wire - single down to 8' above the deck - then double; weighted in at 98 lbs complete - all up including the pivot truck bearing on the bottom of the mast & the 3' high mast-head wind feathers.

I recon with all this new-fangled 'plastic-stuff' (ah ha ah) I could design & build a wing somewhere close to 70 lbs - is that 31.75 kgs.


Look - all you guys - I REALLY AM SORRY for all this - crap - but someone did ask. Now I'll bet 'London to a brick' - they'll never do that again, hey! This is just so blinken difficult. Gary & Doug - I'll e-mail (well Doug -at least) about - pre-stressed laminates & also about - back to back - pre-laminated, pre-stressed laminates. Many times stiffer, in all dimensions, much less weight overall. IMHO

Gawd - I'm outa-here. Ciao & a big thanks. james (back on tractor/slashing c/w 300 ml rain in the last 14 hrs)

 

I covered the weight thingo when I re-wrote the end bit that I lost the first time around.

Those interested in the 'facts' will have to go back to the beginning & re-read it from the start, cause it all changed in the context of it.

Brian Leverton - Mystery's owner & builder - did all the mast design, construction, testing & sailing - with a very little help from me & an ocassional talk to Locki. Wing section was so thick, so far forward & so tall- that everybody scoffed at it. Can't remember anyone trying to lift it to see what it weighed. It was just so big that everybody knew it had to be very heavy. NOT - We used to point the leading edge into the wind so it flew it's own weight down to the boat hulls on the beach - some 80 mtrs away. It took us 2 years to get it wound-up into over-drive before not one cat was in front of us on the water - not even the 18' skiff's. When we left the boat 1/2 rigged (mast & sail up but no mainsheet attached) to go up to a 'crew meeting' occassionally we would watch it - very gently foil itself over so the mast tip was back on the ground - then if the wind veered suddenly again - it would stand back up on this hulls fithout a slightest bother. 1st few times it happened it was very terrifying - after that - we'd laugh & watch everyone get scared.

All that said - I'm sure as **** that we can go a million miles further with development. I just have a few problems with so K1's that seem to know everything & be much better than anyone in the whole world can ever be. I'm to old for all the arguements - I'd just rather go sailing. ASAP. When I can get this 39' tri ownership - sorted - I'll just very quietly put a bigger wing on it (it has 1 there already) & see just how far I can push to boundries. Ciao, james

 

Great stuff, James.

 

Rethinking Sid; the boat is very small, although 8 x 8 metres length and beam, the main hull, even with flare, is very cramped. So the title of this thread is wrong; Sid is no alternative to the B24. It really is a single hander, but maybe okay with one small crew, preferably a sub teenager, certainly not two adults. Also the wing rig is kind of extreme (lol) as to being a B24 alternative. So the original concept has morphed into an experimental design. Sid looks like a skinny insect. However, I'm still happy with that but if being honest, the B24 alternative should be a much larger main hull, greater beam.
Had an interesting sail on Groucho, very light winds (see jpeg) then it suddenly blew up fresh as I was anchoring and ready to drop main ... and the main jammed, couldn't move it, so went up mast and ran a line through the second reef cringle and tried to winch it down ... ripped the reinforced cringle and luff area right out. Now some hard gusts arrived, Groucho rocking and main slamming and banging; had visions of the sail tearing itself to pieces (actually already had started, that would be a good night's sleep?); a couple of very helpful yachties arrived in dinghies. Up mast again with knife and chisel, hacked bolt rope and jammed luff cloth free until finally could stick the knife into the above jammed bolt rope section and easily slide it down track. Cheers. Spent next day, between more wind and rain, gluing and sewing it back together, enough to hoist half sail next morning and sail quickly home. Time for a new main.

 

==========
A bit off topic: thats a very interesting looking dinghy you have there-any other shots of it?
Sorry about the sail.....

 

Hi Doug, very sorry to hear about your brother.
The dinghy is two piece; the other stern section is carried on port tramp. There are four bolts that hold it together in one piece to make around 12 foot, two person sort of light kayak. It is semi round bilge and tippy; you've got to get your posterior down fast when getting aboard (to get CoG down low); it paddles fast and is a good sea boat.

 

Here's a sketch plan and another angle of the bow section on trampoline.

 

---------------
I like it!

 

I like the mainsheet track but can't tell what you made it out of. Is it a layup over a lamination, aluminum, or ??? Sorry to hear about the main but happy there was enough left to patch up and bring you home. Those summer weather pictures are demoralizing but our season will come. We hope anyway.....

 

Hi Gary,
Just gotta say I love your designs, they just look so cool, and unlike anything over here in Aus.
I've seen a few pictures of Groucho on this site, but is it asking too much for a new thread with some details, construction, design ideas, performance info? or you could just sail her (him?) over to Oz so I can have a look see
Thanks for showing your work

DAVE

 

Cav, it took a while to build the track, had to do it in stages. First I vertically bent thin Sitka spruce to form the semi-circular shape (using pegs to hold position) then a couple of layers of thin spruce bent horizontally (edgeways, against the natural bending curve, this took the time) and glued plus temporarily nailed them on top. When that cured, removed fastenings, coved the under surface connection, then glassed and laid short vertical pieces of carbon to make the whole thing non-flexible. Sanding and shaping followed. When that was completed, laid another deeper thin wooden area to the vertical section, crisscrossed more carbon plus more of same, long tows, following the semi-circular vertical curve. Needed the depth for strength and more stiffness. Oh, yes, cut the lightening holes around this time.
I had to build a custom track because I couldn't find the equivalent in alloy. Also I built the solid carbon traveller car to fit - mainly for just the fun and cheapness of building in carbon and epoxy.
The main was no real loss; had served its time. Thinking of a Kevlar instead of sail cloth (which wears away and caused me the jamming problem) around the bolt rope and between the battens next time. Anyone know about this? Or is that a bad idea?