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
If it were me I would stick with the platform size of the LLM. IMHO any smaller would be too tippy and you are likely to scare the kids rather than encourage them. Use the small sail and upgrade as competence and confidence increases.
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.
Just use standard LLM. It will be more stable. The lighter it is the quicker it will slow down when wind slacks off. (thats why the biggest landyachts are not feather weights they use the weight for momentum)
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/
I do have 1 kids mini, or micro.. Its called "hummingbird" and is in the landyacht register. 4 of my girls have sailed it , It currently has 2.8 m sail, 2.5 would be fine. the smaller yacht gives them much better confidence to have a try. the girls have not moved willingly up to a LLM till they were about 12. Make sure you have a really secure seat with high sides, Ihave little panic grab handles on the back axles, dont use any spoked wheels on the back.
also consider some kind of footwell on the steering pedals, or even a simple handsteer.
I always supervise the kids often stopping sailing myself when they are using the yacht as it can flip , or the kids can just fly off on a sudden gust . i also find that its not worth pushing the kids to sail. they will often stop when there are a few yachts sailing , then quietly go for a sail when everybody has gone for lunch
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
I'm about to cut some steel, (as i have the drop saw out, so may as well cut everything I can think of at once!) I'm planning to make the kids mini roughly the same proportions as LY's "hummingbird" How fineever I've got 25mm square x 2mm SHS for the axles. My gut feel is it'll be fine, but never hurts to ask!
Got some ideas regarding steering that i'd like to toss around but i'll have to get a drawing first, too hard to explain verbally, (well with my vocab anyway
)
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.
My experience of brakes on front wheel is they are not very effective as there is very little weight on the front and on sand it hardly worked at all and I ended up taking it off None of the yachts I have used since have had brakes and children seem to get the idea of stopping without them
Re the foot steering I have found as long as kids can reach the pedals comfortably
they handle foot steering well also
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
OK there's a break in the weather here, so some progress on this front.
Got the steeing at 30 deg.
However i have a new problem. Getting the steering by the mast step. I noticed on LY's Hummoingbird you just offset the mast step. Are there any drawbacks with this.?
The alternative solutions i have are moving the mast step back so i can get the BMX gooseneck in. Problem here is the spine is not really long enough for this and i will have to reduce the sail area quite a bit to balance it I think.
Or mounting the mast step over the steering.
I am thinking the latter is the go,
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
OK so now I have 4 options!
Thanks LY, I have the beginings of an idea. I think i will do something simillar, except with the addition of a push rod type system like the class 5's so i can have several foot positions. My little girl is not 4 yet, but i have mates with kids from the same to about 10. So i think some adjustment would be the trick!
Duh
I love this forum!
Thanks
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!!!
Hi Hiko,
I won't be keeping what I end up doing a secret! Especially if it works
What i am thinking is basicall the same system as the class 5's except allow several pedal mounting points and either a telescoping or just several push rods to suit.
I am trying to find some detail on how you allow for the angular variation on the push rod's. I see several examples of a ball joint, bit I am thinking a flexible coupling made polyapproperiate.
I was even considering a 1/4" or 3/8" drive socket universal joint if i can get em cheap enough.
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
"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."
That's exactly what I meant. I have moved the mast position 150mm further forward on the one I am building now. The red flexible stuff is called Nolathane over here. I expect there are other brands. It was turned out if a solid rod to fit the tube size.
I know, it's about time I got some paint on this.
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.
Yeah! I just hunted the WEB and came up with this info' on Nolathane. It is an Aussie/NZ Brand by Redranger Products (Auto Bushings etc) 22mm Part #49080. It can be bought at any good Auto Parts outlet, Repco, Auto Barnes etc.
www.redranger.com.au
It is also available in 32mm. Other info on turning this product. Do not alow it to get HOT as it tends to go chrystaline. Prior to turning in the lathe it is best to cut it to the length required and freeze it for at least a couple of hours and machine it as quickly as possible, you have around 20 minutes to work it before refreezing.
I was given this info by a Redranger technician.
I will also copy this Post to Useful Contacts.
crazy trav down in kambalda improved on our rubber hose connection by using 1/2" or 12mm steel re'inforced hydraulic hose, which is a neat fit in 16mm galv electrical conduit, which is a neat fit in 20mm electrical conduit. the conduit is stupidly cheap, and i reckon youd get the hose from a scrap bin at a hydraulic shop
Can you still get steel conduit?
I was chasing that about 8 months ago for work without any luck! (In Brissie, anyway)
they have racks of it in electrical supply shops, not your big super stores. you may have to send some measurements
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.
