I have been given an old small 2.5m NP sail on a straight aluminium mast, (no taper) The sail has no luff at all. I was thinking of using this as is complete with the wishbone boom (about 1.6m long) for a scaled down mini for kids. The wishbone boom would mean there is nothing solid to hit em in the head.

Would this sail and mast be any good as is, without any luff?
Is the sail size OK?
Should I use a better mast?

I'll try and get a photo this afternoon if it helps.

I have a basic design in my head at the moment. I'll try and get it detailed and post it for approval at a later stage.

The alternative is to use the sail as spare cloth, and cut up the mast for booms?

Thanks

Do you think on a standard llf chassis, the sail might be a bit small?

I was thinking on keeping the dimensions the same as the llf, and just lightening it up a bit.

For the steering here are a couple of threads on the subject of kids yachts....

www.seabreeze.com.au/forums/Land-Yacht-Sailing/Construction/kids-steering-for-Lefroy-mini/

www.seabreeze.com.au/forums/Land-Yacht-Sailing/Construction/Hand-steering-for-a-LLF-mini/

Thanks Paul, the Hummingbird is along the lines I was thinking.

In regards to steeing, I was considering hand steering as an option so that the transition to bigger yachts would be easier. Although I have some doubts that the hand steering is actually easier. Having to steer with 1 hand and manage the sheet rope with the other might be a bit overwhelming. How do the kids go the the foot steering, do the get the hang of it easy enough?

Also just on the foot steering setup, I was looking a a push type of arrangement rather than a turning action, similar to the class 5 and every billy kart on the planet. Obviously this design has come about because of the simplicity, however a more intuitive and symantic action is actually opposite. Aircraft nosewheel/rudder control actually work opposite, in that pushing with the right foot turns right. The downside of this is of course some extra complexity in the design, but still pretty basic, and I'm a bit worried about making it more difficult to graduate to a more traditional larger yacht.

Just on the sail, would the lack of any luff in the sail, and the relatively stiff aluminium pipe mast be OK as is? (I'll get a photo later today, still on holidays)

Sorry for the long winded post, even I am starting to struggle keeping up.

have to agree with gizmo on the sail, use as is.
the kids seemed to get a bit overwhelmed by the kids steering on a LLM, even tho it was fine, they just seem to get into hummingbird and just do it, and it falls into IKPSA's definition of KISS.
i designed and built the chassis and steering of Hummingbird in less than 4hrs( including the undercoat), so theres no harm in trying that first

Just looking at welding the steering into the Kids Mini, and I have a question regarding the angle of the steering setup. I assume gthere has been some experimentation to arrive at the magical 30deg angle. However i was wondering if increasing this to say 45deg might make it a bit less responsive for kids to control. I was also going to gove it a bit more "caster" as well.
worth the effort?

Also i was considering using the brake from the BMX on the front wheel, but i'm not sure this is a great idea. Has anyone tried using a brake on the nosewheel? I doubt this craft will get fast enough to go end over. Also i can put a stop in so it cannot lock the wheel.

agree with Hiko on the brakes, If anything , put a friction brake that rubs on one of the rear wheels, probably the most effective . I never even thought about a brake on the kids yacht.
re the steering. as the angle steepens it gets less responsive , and harder to get to return. it wants to reverse and become a trolley wheel. 30degrees is the bees knees

on hummingbird the foot pedals are actually a lrge plate of aluminiumwith turned up edges to keep little feet in. they are bolted to a mounting that is welded to the front forks, ie in front of the steering pivot. all verymuch like the potty or ludic. my inspiration for it was the potty. I wil now go and take a photo

I hope you come up with a good kids steering option so I can copy it!
I have tried different ideas the problem is kids vary in size so much
Blokart gets around this by having hand steering as this is more flexible as to pilot size
I tried this as well but foot steering is far better IMHO if it can be made to cater for all sizes and easily adjustable
I am sure there is a way I hope you find it
I will be watching!!!

The steering connector we made for our Promo's ended up being a state secret though I am sure Landyacht might be persuaded to supply/disclose said secret. We make them from recycled materials at humungous bank breaking cost. [}:)]

Hi Clemco,

That's basically what i was thinking.

However from what i can see from you setup, the mast step moves as well. Does this cause any problems. I would think the mast step position wold be somewhat critical to the balance of the yacht.

I was thinking of welding the mast into position forward of the peddles. Then provide several peddle mounting points along the spine and steering rods to suit, (or a telescopic rod) The peddle mounting points are simply a few nuts welded to the spine.

Is it possible to give me some more detail on the flexible joints, (I promise not to tell anyone)

Thanks
Glenn

Thanks Clemco, I get it now.

Actually the more i think about it if I made the rod telescopic and as you say clamp the peddle mount around the spine, it would be almost infinitly adjustable. I was originally thinking of several fixed mounting positions, but your system would actually be easier to make.

What would be the minimum size for the steering rod? I know this is dependant on the length required, (This yacht will only require about 500mm max) but I imagine there is a size that is jsut too small. I have some 1/4" solid rod and a small tube that would fit perfectly, but my gut feeling is that would be a bit light.

That joint is much simplier than i was thinking, so that is good!

I've got access to some polyurethane, and solid EPDM, so I'll give that a shot.

grlynch said...

Thanks Clemco, I get it now.

Actually the more i think about it if I made the rod telescopic and as you say clamp the peddle mount around the spine, it would be almost infinitly adjustable. I was originally thinking of several fixed mounting positions, but your system would actually be easier to make.

What would be the minimum size for the steering rod? I know this is dependant on the length required, (This yacht will only require about 500mm max) but I imagine there is a size that is jsut too small. I have some 1/4" solid rod and a small tube that would fit perfectly, but my gut feeling is that would be a bit light.

That joint is much simplier than i was thinking, so that is good!

Yes it is very simple. The stainless tube I have used for the steering rod is 5/8" and 3/4". I'm pretty sure that is the same as we used on our old Fed5s. So it will be fine for the mini. I wouldn't go any smaller. need it big enough to be able to weld those nuts on.

Can you still get steel conduit?
I was chasing that about 8 months ago for work without any luck! (In Brissie, anyway)

I was only chasing it at electrical wholesalers, but anyway.

I managed to get a few spare hours so I tacked some stuff together.



The rear wheels are some that i had, but due to the the size difference with the nose wheel, I think the mas step angle is too acute.