Do it for fun. It's still a LLMINI

If anyone wants a rundown on how I have built a fair few wing masts (and it's not that hard) just ask. It will be a lengthy thing without piccys, cos I havn't done one since I got a digital camera.

A run down on how to construct a wing mast would be great.

Still learning this lingo, what is a 3 section wing?

Another simpler option. Use a spreder off a large water yacht. They are extruded aluminium. I believe they could handle being unstayed with a steel post inserted up the base about 1200mm. I had a rotating mast on my first homebuilt class 5. The mast post was 50 od. I just greased it up. The trick is the mast has to go over the mast post. With a mini the post would only need to be a heavy bit of tube somewhere arround 40 od.

Some wing data for your consideration. I have a Aclass section wing and sail set up of 4m that was supposed to to go on one of my early minis. The yacht capsized within 10m of starting off!. the mini morphed into "pigs might fly"., a 100kph capable 2.5m wide screaming kids terror yacht
in terms of area . I once fitted 3m wing to a CL5. it only ever got 1 opportunity to kill me, lesson learnt. finally consider this At 6m long and 4m wide , VINDICATOR carries a 4m wing,

Um , vindicator with a 4m wing is not only lower aspect that my minis, it isnt even as high!!!!!!!. AND it lifts wheels. do have a photo of the 2 together but wfey has archived it

Heres a Pacific Magic with a 4m wing /sail combo, just a bit too small for racing, but a brilliant concept for upwind. when this rig was put onto PIgs migh fly it just came too life

Heres ths line pic... The thing with wings is its the mast thats doing a lot more work and the line drawing would be a hypothetical.
Also a wire stayed mast twists/ rotates froward which would move the CE forward quite a bit.


Several months ago there was some discussion on the forum...
www.seabreeze.com.au/forums/topic.asp?TOPIC_ID=46374

I had a chat to a guy recently that tried a padded sail on a sailboard, he said "good when it was dry but once the sail was in the water it couldn't be lifted out" due to whe water in the foam in the sail

Here is another version of a padded sail that might work on a Mini landyacht....
www.pdracer.com/sail/unusual/

Clemco said...

Also the height. Height to width ratio, i.e height to CE/width of yacht. A class 3 with a 7m high rig is no more 4m wide. So a mini wing could only be 3m high. To get the takeoff down wind it could be wide, like those short windsurfer rigs, but with a 250wing in front.
I know nothing about wing masts but would like to know more.

Clem, be a bit careful with the widths of Class 3, there are many variations on this theme. Also many variations on the lengths of the wings. (eg the Sanderling mast was just on 5 metres, and Colin always reckoned in a tacking duel he had problems getting past, but he would smoke me on the reaches) I don't think you can make these assumptions of ratios, but you do make a very valid comment about the height of the c of e being a consideration.
I think a 250mm wing would probably be too big as a wing/sail combination, probably around 175 would be plenty, and then the thickness becomes an engineering consideration.
Now if you remember how you and I do the c of e compared to those which Gizmo has plotted on the sails, can you scan them down and use "our" method. I would be interested to compare.
My reasoning is that I do not think that the way Gizmo uses takes enough consideration of the roach at the head of the sail.
My belief of why wings work is multifold.
1 The shape of the complete entry to the rig, ie the leading edge is "nicer" than the round mast
2 With the ability to rotate the mast you have a full sail for starting, tacking etc, and as the rotation pulls off the whole thing flattens.
For all this to work, it has to be considered as a unit, mast and sail. If the sail has shape of it's own, they are slow! We used to call this the "double bump",mast shape, then curve in the sail which did not flow nicely from the downwind side of the mast.

Kiwi, I would have to agree the method that I use for finding the CE is only VERY basic and doesnt take into account of current larger toped sails, Im interested in looking for a better way to accurately do it though.
Just a thought in cutting soft foam rubber, isnt that the stuff that is used in furniture that has toxic fumes when burnt? So the Fire Dept says.... and by the smell of the stuff I believe them. (so if you are going to try it....use a fume mask OUTSIDE on a windy day !!!)

I agree there has to be a better way of working out CE than a cardboard cutout and a plumb bob or the way im doing it.
Can you imagine NASA or the BOEING factory with just cardboard, bits of string and paper planes?.....

Fitted the mini sail to my class5 today to see how it looked. Still have a lot more hand sewing and the battens have to be cut and tensioned it looks OK but not sure how it will go ( as you can see by the battens I cut plenty of the sail ,the long one was the bottom batten). Bloody weather has held up fiber glassing the seat
Cheers
AUS230

this is starting to look like a race!
Hey kiwi, I seem to recall going into john glens front door was an environmental hazard in its own right

I always wondered wat the cockroaches were arming themselves with

Getting close to finishing mini beast, a couple of seat brackets and rear pully attachment to fit then strip and paint hope I get it finished before the long weekend at Lefroy, Its going to take a month to clean my shed after this exercise had to do all the sanding is there because of rain.
Cheers
AUS230