askd same question one post below

strange that you posted chook. I've just rung kiter john chasing pond liner for a floorpan. with a ll the clearing out i unconsciously left enough materials around for one last mini out of my shed

Chook, I still reckon you're getting very good mileage out of your yachts!!!!

The yachts that the esperance blokart assassins sail are screaming fast. gregs mini just goes like a smoothie.. and the boys sail with massive sails

gregs don't twist off its just goes faster. I don't think their chassis could handle even the smallest gulley or ridge, but thats not what they sail on

Must be someone around Adelaide who can advise on this. Open area with reasonably hard surface is what is required.

Hiko said..Must be someone around Adelaide who can advise on this. Open area with reasonably hard surface is what is required.

Beachball's got a few posts on here mentioning Goolwa, and a bunch of salt lakes around Yorketown. Looks like there was an event on a salt lake near Wellington near a skydiving place

As one dodgy welder to another ....... paint can hide an awful lot of dodgy-ness

Chook2 said..
That is looking fantastic Squidley.
Well done mate!!!!

I'd add a seat belt too.

Thanks, and oh yeah for sure I will. Guy I got some sails and a mast from said he knew a farmer that built one and immediately put himself in the hospital! Should be easy to find a lap belt at an auto wrecker.

At the moment I'm figuring out a good way to attach the seat back (it's just resting on the rear sprit(?) in the photo). There's probably some pics on this forum where that detail's visible.

landyacht said..
drill a couple of holes and put a bit of 4mm rope around the steel.. maybe glue some rubber on the setback where it contacts the steel.
best sailing beach in SA gulf area would be port germain awesome beach

Before I read this I ended up making a pair of brackets screwed to the horizontal reinforcing I put on the back of the seat that sleeve over the rear sprit/(pulley whip?) but rubber padding in a few key spots is an idea I could use, cheers. Think I'll make a thread of the build.

Thanks for the tip about Port Germein too

Hey cheers for the yarn on the phone today Ratz.
Your a true champion!

My current yacht is buggered. Its patches on patches to get me through till our local Pink Lake got wet last month. (It cracked the mast mount again sailing at Lake Lefroy last weekend as well). The metal it totally fatigued.
I built it 11/12/2014 so it has covered some really hard kilometres......and endured some high speed spins/crashes.

I even got sick of painting the repairs.
The outer edge of the axle mount split as well and was covered with the next size up RHS tube to stop it flaring open any more. The mast mounts have be re-welded twice as well. The pipe spine split lengthwise at the rear too. (see the big "Jellybean weld" tying the two sides of the split back together. It has a full width 4mm thick flat bar doubler that stops just inward of the RHS sleeves over the ends of the axle receivers. This is welded right across the whole T-axle, I added it as a repair as well.

I've got a new mini under construction and there will be some streamlining involved. (The reason the steering setup has been modified is to be all inside of the body).

The Lake Lefroy Mini is a fantastically simple design that is a real credit to Paul "Landyacht" who designed them.
This is my 26th modified mini yacht build and I haven't ever spent over AUS $650 on the materials of a yacht ready to sail.

Heavily reinforced rear axle off the spine to carry the excessive heavy pilot. The welds were then flushed off and a full depth/width 4mm flat bar added.

20mm "4140 shafting" (I'm trying the stronger shaft as I have bent the 1040 shaft steering head shaft in a few crashes) machined up in my lathe, pressed into 25x25x3 RHS welded then fitted/plug welded into axles with 25mm x25mm x3mm wall, 330mm long internal doublers added where they are under the most pressure. (My 2mm ones were bending when I thrashed them).

This is the first yacht I've built that I fluked the perfect wheel alignment first go. I loaded the frame with 100kgs of exercise weights then checked it. No adjustment was needed and setup with only 1 degree of negative camber. We have proven this combination works best on hard surfaces. (1 degree each side, leaning in on the top of the rear tyres for low friction running).

Two mast positions as my previous yacht has, one in front of the steering pedals and a rear one behind to keep the yacht balanced with my small 5.6m2 high wind sail. Both mast bases angled back at 3 degrees are welded to the chassis.

Then the bolt on mast "stalks" that go up into the 48mm x 3mm x 350 mm long alloy pipe "strengthener" that are fitted inside my Standard Diameter windsurfer masts and retained by a singe countersunk machine screw.

This allows the mast, boom and heavily downhauled sail to rotate as the one unit. Note only the contact areas where the paint has rubbed off the stalk. These contact areas are 1mm larger in diameter than the rest of the 4140 hollow bar stalk for less friction.
The 4 gussets around the flanged base are simply built up with the welder.

See the big centre hole in the (middle item) stalk base, it is offset to the left to allow the 12mm socket head screws to be removed vertically with a sloping stalk. In this pic the stalk would be fitted with the top leaning to the right. The right hand item is the 12mm x 1.75 threaded, 75mm x 75mm x 16mm thick "flat bar" base, to be welded to the chassis at 3 degrees rearward rake.


The masts are raked at different angles (by a combination of reversing the stalks welded to their bolt on flanges at 2 degrees and 7 degrees on my 2nd one ) with these different combinations the rake is from 4 degrees forward for my 6100mm mast for my 9.5m2 sail. 5 degrees raked back and on the rear base for the smaller 5.6m2 sail. This balances the yachts center of effort nicely with these cheap windsurfer sails and masts on my old yacht. Previous yacht pic setup below. I've now shifted the rear mount back another 50mm for slightly better balance this time??

My 9.5m2 sail which is great in a light breeze.
These pics taken at Lake Lefroy. The best sailing surface in the world. 550 square kilometers of perfectly smooth salt.


Now the body to build over winter when time permits.

I'm still on the hunt for a 5500mm Standard diameter windsurfer mast too.

Cheers Guys.

azuli, I love the Demon 9.5. It's a light wind weapon.
The "downhaul adjustment/sail shape" is just phenomenal. It will belly out 450mm if needed. It beats sitting round waiting for wind.
Fully downhauled hard (we can adjust this on the run) it flattens it out to 150mm or less.

If the leaves are moving on the trees I'm into the yacht and gone. Usually achieve 3 to 4 times the measured wind speed. Measured with my Kestral 3000 (I use as a fire control officer. I'm an ex fire captain).

I'm using all hard battens too. (never tried the soft as it goes so well and changes sides easily anyway. I've extended the mast (Greg is a wizard at this. Thank you Greg. ) as we bottom mount them on the yachts.

Below Greg is setting the alloy mast strengthener into position with epoxy and flock and left to dry before building up the new extension bit with carbon. See how the original mast base has been tapered off for 50mm down to a needles edge against the alloy. The mast is sitting on a strip of wood so it can be rolled back and forth to true up the pipe.

To the left of the pic below, you can see the 450mm extension build up then all covered with 7 layers of unidirectional tapering down to 1 at the right edge of the photo. It's then a full cover of woven cloth all epoxied and taped over while rolling the mast on a cranked mandrel while applying the back side of 50mm wide sticky tape really tight, spiraling it along with a 45mm over lap to add LOTS of pressure. This is done because as bottom mounted the mast will flex/bend too much at the bottom 1/3 and buggers up the set of the sail.


It's then heated to 60 degrees for 7 hours to cure. The mast is supported on blocks in 3 places so as not to induce a curve. Temp is regulated by shifting the blow heater further away from the old cardboard sail box or restricting the outlet size. Pretty high tech eh?


The sail is standard except for the eyelet triangle and boom strap I added at the clew. goes really well in 5 knots of wind. It points really high once you get that apparent wind working. The wind never changed direction in my plot below and the whole salt area was as smooth as marble. Got to love Lake Lefroy. Kambalda West Aust.


Yes I saw a few big sails for sale in QLD. I'd love them, but the freight to Esperance WA would be as much as they are asking. Bit of a bugger that.
Cheers.

azuli said..
By moving the clew load point down foot below the batten, it may change the load path, and the leech may be a bit looser than original design.
Perhaps it's worth experimenting with a line from end of boom to the clew pulley to distribute some of the mainsheet load, it should tighten the leech a bit for light wind performance.

Hey I will certainly try that next outing thanks.

azuli said..
The soft battens have draft 10% further back towards centre of chord. They are best in < 10kns wind on raceboard, we switch to the stiff carbon battens in 15+kns as they are more stable in stronger winds.

Well there you go I had no idea about that. It just worked well and I hadn't bothered to play with it. I'll now have to experiment and see if it shifts my center of effort too far back?

azuli said..
Am interested to hear how the demon compares to the Neil Pryde RS Evo sails in the pics at top of page. I expect they need a bit more wind to get moving, but do they have better top end?

They certainly motor. The Demon only gets used in light winds so not really much of a comparison to be fair. All the Evo's (which now measure differently with the triangle added below there original clew) have had their leach adjusted for less twist-off when sheeted in HARD. Some times it takes a few goes unpicking the batten pockets overlapping the back 3/4's of the sail (leave the front 1/4 unchanged/ still stitched up))in a nice gentle curve and re-sewing/refitting the batten pockets to them to get it drum tight, as we use so much down haul.

You can let go of the sheet rope at very high speed (above 80kmh on my 5.8) and the sail will just sit there feathered with the wind, without a single flapping movement.

See the change in the diagonal black line up my 8m2 (7.8 + clew triangle) sail, where its been overlapped 30mm at the back on the 4th and 45mm on the 5th batten and it's changed the back of the leech slightly. It's a Severn 4600 25 IMCS hard top mast with an alloy mast extension on the top. Been re-enforced down at the base with 7 to 1 wraps of carbon up to where the windsurfer boom would sit too.


Greg uses 36 to 1 down haul on his sails and it's adjustable on the run. His setup is much more easily adjusted than mine. My set up now being just off the base of the mast. I will change mine when the new yacht is rigged. I've got the second 6 to 1 sorted ready to go onto the end of the one that's already there now. Just have to re route it out my boom.

Greg has also cut the leech off a lot of his sails to increase the aspect ratio and boy do they handle well and point so high now. They go like blazes too. He eats me with my standard Evo's. He's consistently 10kmh faster than me. I'm usually 1.5m2 more sail than him, as I weigh 40kgs more.

Greg in his yacht below. (These are LL mini yachts that we just run 26" x 4.8" wide fatbike tyres on for floatation on our soft lake surface here in Esperance. We go back onto barrows for racing at Lefroy).
His cut sail and he's removed a few more wrinkles on the 5 batten since this was taken.


Sorry my photo editor and seabreeze dont love each other. Need a 1/4 turn sorry. My dumb thumbs eh.

Thanks azuli for the complement.

Yeh we are always altering our gear. We call it "riggin' and friggin", as we are always stuffing round trying to improve speed and pointing higher.

I'm taking in the leech here to reduce the twist off when fully sheeted in.
You can see the black texta line it will be overlapped up too.
I actuall re did it again after this, as the 20mm overlap indicated here wasn't to my liking when I rigged it up.

So I unpicked it all and changed it to 30mm on this batten. (If you look at the previous photo of this sail in the post above on the yacht, you can see I had to overlap up to the bottom of the letter "AUS".)

Sometimes it turns out to be a bigger job than expected but the results really shine and make it all worth while. Once this was done I altered the next batten up twice as well to get it to sit perfectly.(45mm overlap)


Sheeted in really tight with huge downhaul, then I was happy with it.

All part of the fun to modify something and then go out and see if it works. We know a great deal about what doesn't work now......
Another little one (that started life as a huge one) by Greg.
Cheers.

When racing the first mark is directly up wind and then where ever the commodore desires.
Some times the upwind is quite challenging.

If the wind is strong (we are travelling above 60kmh), we can really point into wind and hammer downwind.
When racing the course usually involves 5 marks like on a dice only going round the center mark once each lap.