New LLM build, help please

Hi guys
I'm new on here and finding all the information fantastic. I can't get to bed before midnight, catching up on all the posts! I'm just gathering materials to start building a LL mini, thanks for the great plans.
A couple of questions -
I will be doing most of my sailing on beaches. There's talk about moving the mast forward, is this the way to go for beach use?
Also mast rake - hoping to use uncut windsurfing sails, is mast rake at two or three degrees the right option?
Thanks for any replies

Thanks for your advise Hiko,will see how the build develops as i go.
Still collecting parts at the moment.

All looking good so far,

My guess would be that the weight of the [single arm] fork being on the right, is causing the wheel to naturally lean towards the right.

Once bushes are installed, and the landyacht is "road weight", with sail, rigging, seat and pilot - the wheel leaning by itself will not be as noticeable.

When on the move - your feet are on the pedals and you will be too busy having fun to think about a lazy wheel leaning over when parked.

Can you do a decent sized side view photo of the front wheel and the whole steering assembly?
Fit the bushes so that the steering is aligned as it would be when finished.

Then we can check your geometry for you.



stephen

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Moneybox said..
Just a question on wheel alignment.

I'm not working in a jig so it's difficult to check that the front wheel alignment is correct. I have the shaft at 128 deg from the fork so getting a square onto it is difficult.



With the chassis weight sitting on the front wheel (bushes not in yet) the wheel wants to lay to the right. Should the front wheel stand upright if the alignment is correct?

That is looking real good.

Nah they lay over where ever they are pushed. The weight of steering pedals helps to hold them in position and as Stephen said the friction of the bushes helps too.

With the bushes fitted and keeping the square right there as in your photo, if you take a nice straight bit of steel and place it on the left side of the front wheel (opposite side to the support arm) contacting the tyre both front and back and laying across the axle, you should be able to look down vertically from the top and see if it runs parallels to the chassis.

With the wheel removed and the axle in between two bits of hard cardboard (so as not to curve the axle between where the bearings seat) the alignment can be altered in a vise with some brute strength, or the use of some leverage.

It's quite malleable really and easy to adjust to rectify where the welding has pulled as it cools.


To get everything spot on and all wheels in alignment, this is my method.
(Sometimes it takes a few goes on each side to get the rear wheels without any toe-in/out.

For the final wheel alignment I load the completed/rigged yacht, with my body weight in exercise cast weights. 108kgs.
I position the spine of the chassis exactly over an extended centre line drawn on the floor of my shed. (Extend this line well out in front of the yacht. The further forward the more accurate the wheel alignment will be.)

Line up the centre of the front tyre on this line as well with wheel exactly upright.

I then lay a steel rule horizontally across the top of the rear axle (it will be parallel to the centre line) and contacting both insides of the tyre walls on that side of the yacht and use this ruler to position a set square (that is sitting on the floor with it's blade vertically up and laying against the square RHS axle, blade edge just touching the rule) Now make a mark on the floor directly under the corner of the square. If for instance the steel rule is 25mm wide, remember to add this to the distance from the centre line. We want an exact measurement from the inside of that tyre's edges/at axle height transferred down to the floor.

Now measure exactly this distance from the centreline out to this reference mark on the floor.

Now take this measurement out as far forward from the front of the yacht as is sensible/room permits and mark this measurement out from the extended centre line. This mark will then be the exact width from the centre line of the rear wheel at axle height on that side of the yacht.

It is now just a case of standing the very corner of a set square vertically on this mark (with a bit of bright electrical tape to indicate axle height) and eyeballing it (from as far forward from the yacht as you can) to see if the line from inside of both the front and rear walls of that tyre aligns with the edge of the square at axle height. If it doesn't then it's axle out of the chassis and into the vice for the same treatment as the steering head.

I use a cheap laser pen to eyeball/do this as the beam highlights the tyre walls from a greater distance. With a bit of fiddling I can get them spot on.

Running on Lake Lefroy when the salt is dry you certainly know when the alignment is out. They really howl. I crashed in September while practicing and bent one of my rear axles. It had 87mm of toe-out, 3 meters in front of the yacht when I checked it at home.
The rear tyres were completely stuffed and down to the canvas.

Hope I've got my process clear enough for you to understand.

Yes, it's just that my yacht is carrying a lot of ballast with me in it. Need everything spot on with the very least amount of rolling resistance.

Just pick up the front wheel of your yacht keeping it a 100mm clear of the floor and roll it across a concrete floor and listen to the difference in rear tyre noise. Alignment makes an enormous difference.
Good preparation always helps speed wise.

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Moneybox said..
I'm surprised that you aim for such accuracy in the wheel alignment for what I see as a toy.

Careful you are sounding just like my wife!!


Good luck with your gold prospecting.