Monday, December 10, 2007

There is a continuing debate on Sailing Anarchy with the Phoil Phanatic Doug Lord about foils, wands, and flying. I recently posted this list of things we did in camp Stevo while trying to make moths foil:

"Here is a list of at least some of the experimental foil setups Andrew and I tried up to about 2005:
* Bow rudder and foil plus main foil, no wand,
* Manual incidence control of bow foil.
* Bow and stern ruders with centreboard, foils on bow and board.
* Bow and stern rudders with foils and no centreboard at all.
* Foils on CB and rudder, no flap no wand,
* Foils on CB and rudder, trailing edge wand on both,main foil with dihedral to induce righting moment with leeway.
* Manual adjustment of main foil incidence,
* High rate manual rudder flap adj, via tiller ext for reaction to waves.

We were the only people in the Sydney Moth scene trying anything at this time. There was not a lot of sucess from these experiments and only a few ideas are worth saving for the future.

We then went to the Melb Moth 2005 WC and saw how well the Ilett system worked, talked to John who was very generous and helpfull, and came home and started doing it his way.

With the exception of Andrew's tilt rudder system adopted by the Bladerider all of our subsequent work on moths has been in learning how to make the foils as strong and as light as the professionals.

We have tried and will develop some more ideas to try WRT to general moth layout but for now we are content to make only subtle development changes to the foil system. "

Sunday, December 2, 2007

The new main foil has been sailed with sucess. It seems to take off earlier than the old one and it weigh about half as much. It floats nicely, certainly in the ball park with the factory jobs.


The race was 3/4 drift with the last lap getting enough wind to fly. I was with Dave when the wind came in and seemed to get out of the water as easilly as he did. But he has heaps more speed and sailed away to win. Then Grant caught me too.


Some rig develoment to do when I get back from the Canoe WC, but I am looking forward to trying to get the moth up to speed. It should be a lot easier than it used to be with 10 boats and a lot more knowledge amongst the sailors who are all willing to share.


This is the new foil with the No-Gap hinge. It seems to make a difference.


Now it has proven to work I can paint it nice and shiney.

Sunday, November 25, 2007

The Moth fleet at St George continues to grow. There have been new boats in each of the last three weeks and there are a couple more coming before Christmas. We will start 2008 with 10 quality foilers plus a few low riders and even some scows.

I have some catching up to do. While I have been sailing the Canoe in preparation for the IC worlds, the younsters have been practicing hard.

I have almost completed thenew main foil and might give it a try next Saturday. Its club Champsionship, high tide and hopefully a good foiling breeze.

I need to spend some serious time on my moth sailing, some equipment updates and tuning. There is really no reason the old Tiger can not be as good as the newer boats.

Tuesday, November 6, 2007

The smooth foils were an improvement but the young guys who sail every week are now well ahead. I will get more serious about some moth practice once the Canoe Worlds are over.

Sunday, October 28, 2007

Some progress at last. I have molded a new main foil and centreboard. Different technique to last time and considerablly lighter, at 2kg. Will have to see if it is as strong as earlier versions.

Meanwhile had a sail of tiger last week and determined my sailboard mast was not stiff enough. I had some more bits of tube so have made up a stiffer one for next time.

On the good side the new AMAC 10% style mods to the wand and flap linkage has made the boat much more easy to sail. No crashes, no launching and easier take offs. The boat feels safer now to drive it hard without fear of launching at high speed. The old foils are home this week for a spay job, smooth is fast.

Wednesday, September 19, 2007

Andrew and I had a sail of Tiger the weekend before last. Marginal conditions but we figured recent trimming of foil and wand angles need further adjustment. Foil is back at home this week for some minor padding so we can maintain the necessary angle of attack.

Off on Holidays soon, so the workshop will get a clean out ready for some foil making. Need to start out getting our verticals down to weight and up to stiffness. Then some experiments with different ideas for horizontals. Have invested in some much needed vacuum gear.

All in preparation for the 2008 Chainsaw replacement:




Monday, September 3, 2007

Chainsaw is gone. Eric has it in the Balmoral shed.

It now time to get back to the shed and the foil mold and do some improvements as both Andrew and I plan to make some new moths in the next 12 months and some development work is needed.
I have bought a vacuum pump so at least we should be able to shed some weight from the laminates. We also have some new ideas for manufacture and design to try out so now with the workshop warming up expect some new Stevo creations to emerge.

Sunday, August 26, 2007

Some moth activity this weekend even if I did not get sailing.

Eric has committed to buying Chainsaw. He had a test sail late last season but has had a busy winter, he finally decided he needed a moth for the summer. He will sail out of Balmoral in Sydney.

I spent a few hours yesterday afternoon with Tiger on a Chain checking foil angles and wand settings. Luka was there to assist with knowledge gained from Garda and helped me make a few adjustments which should improve take off and height control.

We improved the fit in the case and restored the angle of attack back to a few degrees positive. I also found some slipage in the wand pushrod and reglued one loose joint. This will mean the wand flap response will be much more positive and more reliable.

Looking forward to a sail of the boat on the weekend after next, as next week will be the last weekend away from sailing for the next 8 months, and a rare chance to do something different away from the water.

Tuesday, August 21, 2007

TOC AUS 9343

The Tiger is of course a more dignified lady.
It eventuated that I had been buying various Thorpe moth components for my various boats, over the years that Mark dominated the (at least) Sydney moth scene. After a frustrating 04/05 season I shouted myself the biggest part of the Hungry Tiger, a new Hull, which pretty well completed the whole set.
It was probably a year or two too late as the foilers were already dominant, but it was something a moth fanatic had to do. Sailing the Tiger with conventional fin and rudder, and doing it reasonably well in moderate to strong winds, will remain one of my most rewarding and proudest sailing achievements. Racing other moths and bigger boats around the course at amazing speeds and on the edge of control was fantastic.
But I knew that era was over so Mark built the hull with the extra hard points needed for foil, wand and gantry. This was built concurrently to RTFM/Revelations #9344 so it can be argued that either boat is the last Hungry Tiger built.
The spars are genuine Thorpe and the wings were the Prepreg tubes made with Snubby for Chainsaw. All nice and light.
The foils were made as wet layup in a new mold as Fastacraft clones. Andrew had designed the tilting rudder box now employed by Bladerider so TOC was the second boat to employ it after his #9323. I initially used a big 900mm span rudder foil in an effort to lift my 85kg but this year I bought some BR prototypes and used one on each boat. A box Gantry was fitted earlier so now the configuration is almost standard.
My 5 year old Truflo sail is getting tired and is too full for fast foiling so late last season I bought a P&B sail from John Ilett. It is a reasonable KA clone but since it has the fashionable huge luff round the old faithful STIFF Thorpe mast does not work. I tried it but the sail just would not flatten. So now I have recylced a sailboard mast which more closely matches the requied bend and stiffness.
Now to learn a few lesons about foil angle of attack and wand settings from the Garda experience of others and the boat should be up and flying again for the new season.

Unless someone decides to buy it of course.

More on Chainsaw


Some history:
Chainsaw has had a few lives.
The first version was a ply hull with balsa/carbon laminate chines which I sailes at the 03 Milang nationals with alloy wings and again at the penultimate 04 Cootharabah nationals with carbon wings. At that regatta the laminate chines split from the transom and the hull was roughly patched up to compete on the last day.
After the regatta it was used as an experimental base for some early hydrdofoil experiments, including a bow rudder, trailing edge wands, flap less main foils, dihedral and a few others I forget to save embarrasment.
That first hull was written off at the end of that season cut up and dumped, and in the winter of 04 I built the second Chainsaw hull which became the basis of the 04 version of my moth.asn.au biuld a ply moth series articles. This is the best hull shape of the series, most like a modern Hungry Tiger/Prowler/Bladerider shape.
But based on the earlier foil experiments I put the mast and wings much further forward in an effort to separate the foils without going to a gantry. It also had low freeboard, flatter wings and an elevated trampoline in an effort to reduce wndage. Foil development however progressed very little, with carved timber foils and poor upwind performance coupled with poor downwind height control. Not huge sucess as a foiler. This is the boat I sailed baddly and slow at the 05 Black Rock worlds.
The season ended with me sailing the boat with conventional centreboard and rudder, winning a heat of the NSW chaps in light winds and giving some confidence in the hull shape.
The boat was stripped down and left without decks for a year to dry out, while I sailed my new (Hungry) Tiger on a Chain which reused the carbon wings, plus Thorpe mast and boom.
Chainsaw was resurrected in the winter of 06 while I was concurrently building my new Development IC. Both have unstayed masts and so mast and sail development exchanged ideas between the boats.
The 06 Chainsaw involved stripping out the hull, relocating the fincase and installing the new tube mast step a bit further aft. It has struts to elevate the alloy wings which are further aft and cantelevered out of some glass tubes bonded to the struts. The lot is a relatively cheap experiment in configuration and structure, but is remarkably stiff and strong, and surprisingly light. Mytermis minimised. I simply eliminatd as many moth components as I could.
06 Chainsaw benefits from the foil mold I built after the 05 Worlds with generous advice from John Ilett. Both TOC and Chainsaw have home made copies of John's early model foils and this has at least assured reliable if not competitive foiling. At least we stopped breaking things and losing them in the bay.
So Chainsaw now is a viable foiling moth which is availabel at a reasonable price because not very much of it actually cost me very much, mostly being left over bits from other boats.
It has encouraged me sufficiently to build furter on the theme and I will be building a new improved, lighter, simpler, faster and even more minimalised version when I have the shed space available.

Tuesday, August 7, 2007


This a pic of my other moth.
A collection of components arranged in a somewhat different configuration than what has become moth normal.
All who have sailed Chainsaw think it is a good idea and well worth pursuing in my next moth.
Consequently I am selling off both Chainsaw and Tiger on a Chain so I can get stuck into a new lightweight and maybe even more radical version of this experiment.
Ads for both boats are on the Aust website For Sale page.

Just Starting

Since everyone is doing it I thought I would have a go too.
This BLOG will report on my Moth activities and ideas.
I like to think I can help the moth class continue to be the hive of inovation and development it has been for over 75 years.