Forums > Land Yacht Sailing Construction

New build

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Created by Bynorthsea > 9 months ago, 20 Apr 2018
Bynorthsea
104 posts
20 Apr 2018 2:51AM
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A few months ago I set out on a new build. Main criteria was that it could be knocked down to fit in the car, as far as possible meet the 5.6 spirit regs, Y frame and set up to use uncut windsurf rigs. Dimensions were arrived at by a lot of measuring of other yachts and lots of drawing. The weather over the winter has really been against us for sailing but it's now had some testing and a few mods where needed.

The basic frame is 60x40x2 and the axles clamp on the spine like a beach runner.


Axles are skis, the plastic surface and metal edges removed and then two laminated together before trimming to fit into the 60x40 section, they work well.



Front end has a removable yoke so I could experiment with simple suspension.


The mast pin adjusts for rake and slides along the spine for position, made from what I had the 4mm plate flexed in its original form but is now strengthen an is ok.



My first experiments with uncut sails used a wishbone but after lots of advice on this forum, thanks guys, I am now set up with a boom. Originally I set up the down haul cleated at the base. To try and achieve easy on the fly adjustment I have now set up a system on the boom I'm using a modified heavy duty drawer runner with a camcleat, another rope is attached to the end of the slider and then through a vang with camcleat, so far it works well.






The seat slides in tube mounts and can be adjusted to take the weight further back and I also have a set of axles set up with big beach slicks.




And ready for the beach.



Apart from a couple of strengthening mods the yacht has worked well just getting the weight lower an further back makes a real improvement in stability, I am still learning how to get the best from the uncut sails but when you find the sweet spot it flys.

BenBoulder
WA, 261 posts
20 Apr 2018 8:48AM
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Awesome build. Very clean and great ideas.

kennatt
135 posts
22 Apr 2018 1:48PM
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fantactic,did you make the seat yourself from a mould or is it modified from something else,wouldn't mind making or acquiring a seat like that. for my proposed build

Bynorthsea
104 posts
22 Apr 2018 2:58PM
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Both mouldings are grp and both made on sacrificial moulds made from timber and building insulation foam. After getting the shape correct the mould is covered with brown parcel tape to release the resin. After layup the surface is rubbed down and top coated.

lachlan3556
VIC, 1066 posts
24 Apr 2018 12:42PM
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Great thread. Best get out sailing with that mini!!!!

Sylk
WA, 215 posts
26 Apr 2018 9:33AM
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Wow very impressed with your workmanship and build quality.
Also some very neat solutions to some of the fiddly bits.

Love your improvements to my mast base in particular how you have done the rake adjustment bolts.

Iceman
7 posts
16 Jul 2018 6:00PM
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I?d like to steal your steering rod design for my Nordic-combo. It looks like your using rubber to get that flexibility needed. Could you elaborate on material/"scrap-parts" used?
/iceman

Bynorthsea
104 posts
18 Jul 2018 3:39PM
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Can't claim any originality for the design. Mine uses some heavy wall rubber tube that I had, with a second piece of harder tube pushed through the centre, it enters up into the stainless tube by about 50mm and is bolted through with M6. The overall length is adjustable with the two sizes of tubing sliding inside each other. It has a safety strap made from webbing in case of total failure. The time consuming bit was getting the geometry correct so that so that the joint does not get too bent when being pushed, I just experimented with different connection points on the steering yoke and foot bar till I got it right.
If you search there are quite a few posts on here about similar systems, the commonly suggested link is made from hydraulic tubing or as used on some commercial yachts polyurethane rod.
Hope that helps. Les

Hiko
1229 posts
20 Jul 2018 4:25AM
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Man thats a sticky beach!

IPKSA
177 posts
5 Aug 2018 3:51PM
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Lovely build and very well thought out :)

Bynorthsea
104 posts
10 Dec 2018 5:34AM
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Just had the last sail of the year so time to review how the yacht has done. The first thing I am pleased about is that it has not broken though it has been mainly sailing on tarmac after the storms destroyed our local beach, so not too rough. The tarmac sailing is on a very large airfield and always as a club event so there is always other yachts to sail against and this has been essential in getting the best out of the yacht.
In general the yacht is easy to sail, predictable and in a sweet spot fast.
It took some time before I could find a balance and understand how to get the best out of the uncut sails. Balance mainly meant moving the mast back and more rake, the negative rake built into the mast pin has not been used. As for sails I've used from 6.1 to 4.1 cammed and uncammed compared with the good conventional sails Ive found that the windsurf sails have a narrower sweet spot when they are a match in performance. I have used my uncammed sails more than the cammed, I find that the uncammed are faster though the cammed sails do have more low down grunt. I had originally set up an on the fly downhaul but I didn't find it useful so that's been abandoned, I have set up an adjustable outhaul which is very useful on the uncammed sails for low down power. Getting the outhaul just right, not to tight seems to be essential for good power overall as is just the right amount of loose leach, too much and the sail is dead.
So now the question, I can match or beat other minis reaching and running and occasionally up wind but not consistently I'm usually a couple of degrees off and run out of speed more quickly. Is this a compromise I have to live with or are there other tweeks I can try, are some windsurf sails better up wind than others???
Seasons greeting. Les

Chook2
WA, 1244 posts
11 Dec 2018 7:38AM
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The biggest improvement I've found going upwind/downwind is a really delicate touch on the sheet rope. It's so much more important in lighter winds to live by your telltales.

These bits of wool are your guide. Mine 4 sets up the sail are simply sticky taped on. Need to use a dark colour (I use black and red on opposite sides of the sail 50mm vertical separation on each side for each set. The dark colour helps when viewing through a darker coloured sail fabric.
I have two vertical lines of telltales. The 1/4 cord back from the mast I use in really light wind and the 1/3 from mast for normal sailing.

Practice and find out how they stream for maximum power. At different heights up the sail they sit/stream a little differently.'

At all times they MUST be streaming to achieve the sails full potential. "If in doubt let the sail it out"

kennatt
135 posts
11 Dec 2018 6:38PM
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Not sure of the effect of cammed or uncammed sails with a land yacht. Windsurfing wise ,cammed sails are better upwind,they hold their foil shape better. All of the course racing events were on a square course with direct upwind and down wind legs so uncammed sails just didn't work as well. Theres a bit more going on with land yachts,I have a mini with a fixed mast base,but can extent the front wheel to base distance by a considerable amount ,if I extend ,even a couple of inches,past the sweet spot that I have found works best ,in a gust of wind the yacht veers upwind by a few degrees,conversly reduce that distance and the yacht shoots off downwind.As the gust passes returns to original course,
Basically I am moving the centre of effort behind and then in front of the centre of lateral resistance,causing the change in dynamics . So yes sails may help but it could be worth experimenting with mast rake, may have a similar effect,
And tell tales are a huge benefit.

Hiko
1229 posts
11 Dec 2018 10:16PM
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I have found raking the mast forward or back in an oval mast step to be a simple way to achieve balance on my mini yachts A wooden wedge is used to alter the rake to suit.



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"New build" started by Bynorthsea