Here is a sightly different approach to a class 5 yacht using a "T" Axle.
(I had to do something on a cold rainy day)
This is a Concept drawing ONLY.. use or reject the ideas as you wish.
This is a color version of the design, there is also a higher resolution black / white version in the photo section
Looks good!
Correct me if I'm wrong, but isn't the steering a little bit off -- there's bucketloads of negative caster there? Don't you want zero or slightly positive caster?
Also what would the torque loading be on the main chassis tube, bearing in mind how much leverage the mast has, and how long the tube is before it splits into the rear axle?
I've never even ridden in a landyacht so my ideas might be way off the mark 
I have based the thoughts for the steering on "Wildfire" which worked well (but foot steering not tiller).
Also have in mind the angle of motor bike forks...(I think Harley Davidson fas more to invest in R&D than me) and who's going to tell the local bikies "you've got it all wrong"!!!!
The main spine and mast step is based on the "Pacific Magic" design, the steel "T" section would be approx 500-600mm (same width as the seat)
Draw a line down through the axis of the steering pin, it should intersect the ground in front of the contact patch of the wheel. This is positive caster and makes the steering self-centre (like a wheel on a shopping cart).
It does in your previous yacht, it does on the harley, but it doesn't in the new design.
Anyway if it works, it works
Point Taken on the caster angle ... ( CAD Drawing changed on PC) thanks
Still haven't decided if the front end would be single sided or forks on both sides.
Any suggestions on "Names"?
I'm too lazy to draw it up...
or HYPERACTIVE or even Attention Deficit Syndrome.
The sandpiper steering was "light" mainly because the seat was leaning back a fair bit and this reduced the weight on the front axle but it steered quite nicely .. untill we added the jib...then in high winds and a soft surface it wouldn't turn at all. We even tried horizontal wings on the front forks to keep it down at speed (didn't work) the best way to turn in high winds was lean forward a bit, slacken off the jib then turn.
For more info on wheel caster ... en.wikipedia.org/wiki/Caster_angle
Bike bits sometimes are ok..you might be better just getting the upper and lower bearings and the cups they run in and sit them into a piece of tube ( this is what the sandpiper used)
Just another point in using bike wheels, have a read of the class 5 rules....
"WHEELS, There will be two non-steerable rear and one steerable front wheel. The overall diameter of the tyre shall not exceed 650 mm. Wire spoked wheels are allowed provided the spokes are protected by covers on both sides."
Mind you for a Class 6 bike wire spoke wheels work fine as a front wheel but they collapse as rear wheels , Plastic bike wheels are stronger BUT the tyres will roll off at high speed .. "been there done that!!!"
A thought in the design of "this" Class 5 was to use a clamp on the main spine tube for front end. This would enable changing to a roll over front end with just a few bolts if you wanted to ... even between races!!
This is also the reason that the rear wheels have zero camber (ie. straight up and down), this enables a change in the main spine angle to the ground, without re-aligning the rear wheels.
To the people that have asked....the CAD program used is avaliable FREE from
www.cadstd.com/
Its a simple FREE Cad program and works very well, still not as creative as a pencil on the back of a beer coaster but the results from the Cadstd are GREAT.
Im feeling that I might rename Susans yacht " future boy"
have a good look at the tyres/rims for bikes these days. tyres up to 110psi (bmx) double skinned rims, kevlar tyres .
Howdy Nebbian,
Where do you shop?
Every shopping trolley I get hold of has all wheels with minds of their own, all wanting to go in every direction, but the one I want them to!
.
[/quoteWhat you are indicating is that bike rims and tyres are suitable for class 5 landyachts.I would have thought that the casings would not be capable of handling the stresses that a class 5 would subject them to eg. weight/speed and cornering.
After all they are bike tyres,where would you stand if a accident occured with insurance
Back when the tyres used to peel off,and the plastic rims shattered we would carry spares. These days I carry spare yachts. Travis Bartlett is currently experimenting with thos very wheels. In the old days we were not absorbing the shocks and bumps very well, but I think we are learning.
If you dont like the look of the yacht ,dont get in it.
In Argentina the strong wind rule was"no-one will be forced to take thier yacht to the starting line". Ie If you dont feel safe ,dont sail
NO I WOULDN'T use push bike wheels/ tyres for a class 5 ( way to risky).....
I might ONLY use a 16" push bike wheel / tyre for a Class 6 and then ONLY for the front wheel.
(Just my personal opinion)
I've got a set of plastic rims being modified in adelaide at the moment,and the set of Carbon rims we tested at gillies failed due to the wrong type of epoxy resin being used. I'm trying them on te minis at the moment.
the experiment is very much early days as I want to fit them to a OTT mini that wont fade away from my fertile brain
I'm into cycling more than landyachting and you'd be amazed at the technological advances in bike wheels of late. The downhillers use very strong wheels and give them a hell of a hard time. However it'll cost you up to a couple of grand a pair. For that reason I'll be sticking with wheel barrow wheels.
Mind you, you should see the new pair of alloy wheels I just picked up from DR. They're from the batch Bill got made up, very nice indeed!! 
Now I just have to decide if I put them on my PM or save them for my next project??
Select to expand quoteMany thanks Gizmo message loud and clear,would have thought that landyacht could have given the same answer but didnot
But then I'm not GIZMO
Select to expand quotehills said...
I'm into cycling more than landyachting and you'd be amazed at the technological advances in bike wheels of late. The downhillers use very strong wheels and give them a hell of a hard time. However it'll cost you up to a couple of grand a pair. Mind you, you should see the new pair of alloy wheels I just picked up from DR. They're from the batch Bill got made up, very nice indeed!! Now I just have to decide if I put them on my PM or save them for my next project??
[/quote ]
I priced some 20" carbon rims. $599 each!
If those alloy ones you've got are the ones I think, they use a 15mm stub axle? build your set up so you dont weld the stubs as they do snap from time to time(regularly)
Yeah I was thinking of doing that as the stubbs only have a couple of cm to attach to the bracket. That's also the reason I thought they might be better on a Lefroy Mini 
good thinking 99. those rims are soooooo light. when they were originally made I asked that they have enough metal on them to machine out for a6204 bearing, but what would I know. Those little 6202 bearings used to flog out very quickly when used on a cl5. they would be heaps better on a mini
( yes people, HEAPS is a scientific measurement)
Yes a few heaps = 1 sh#tload. A very old ISO standard
There seems to be a bit of a delay with my lefroy mini project, something about fingers and lawnmowers!
Nice telltales Landyacht!
Do you find them useful when sailing along? I've been meaning to fit some to my windsurfing sail, I'm consistently slower than my mates (even on their kit) and think it might be to do with oversheeting. Been mucking around with sheeting angle anyway.
Is there a right place to put them? Do they serve any purpose if they're on the trailing edge? I was thinking of putting them about 2/3 the way back from the mast so they'd tell me if the flow was separating when it got there, but that's one place where they're not on your sail...
Telltales placed by sailmaker. the trailing edge ones eventually flog out the sail.
I put some in a line 1/3 back from the luff, and a few on the trailing edge.
Re: minis . chassis are finished, prefered pain to boredom.
If you look at some ofthe last postings you will see bandaged fingers for scale and dating purposes. I have 1 front fork and a pedal to weld than those bits can get painted and I can start doing some drawings for seats. that is where the art comes in
From the "How to sail a Hobie Cat".. the use of tell tails
SAIL POWER
Face the sail in order to pay close attention to the trim or adjustment of the sail. When the front of the sail, just behind the mast, luffs or flutters in the breeze, you lose power. To start moving, pull the sail in just enough to stop the sail from luffing. There are also short ribbons hanging on either side of the sail. Follow the diagram of sail and course adjustments using the "tell tails" to get the most performance out of the sail for all angles of sailing. The tell tails react to air flowing over the sail and will help you see that the sail is pulled in too tight or too loosely. If you pull the sail too tight you will stall the sail power. Ease the sail out until it luffs, then pull it in just a little until it stops luffing. You will adjust the trim whenever the wind changes direction or you change course.
AERODYNAMICS... Can someone define aerodynamics and what would be allowed and what wouldn't in Class 5 rules.
As a lay down seat to some degree is aerodynamic or are the rules refering just to the chassis?
I have noticed many pics from overseas that the Class 5 yachts have very slick almost enclosed seats.
This is how the Class 5 rules state it....
9. AERODYNAMICS, Fairing or other devices of an aerodynamic nature on any part of the yacht chassis are forbidden.
For Example... Aerodynamics and the use do thse yachts fit into Class 5 specs?
and is this level of Aerodynamics ok?
