Keder?

  • 12 Feb 2020 18:59
    Reply # 8743176 on 8742744

    Nice project. 

    My gunter-rig mainsail of similar size uses this bolt-rope & groove system, I don't think there is any need for the pvc tube, the wooden groove is strong enough. Also, I don't think you need the groove so deep, it can be nearer the surface and your batten will be stronger. I would avoid varnishing or painting the inside of the groove but every season plug the ends and saturate it with linseed oil or a varnish like Le Tonkinois. 

    I'm thinking about a similar system currently but also trying to articulate the battens and get some camber in the sail to keep the experts happy! 



  • 12 Feb 2020 16:20
    Message # 8742744

    Keder, see https://www.jjcarter.com/keder2/what-is-keder is of common use for attaching sails to masts and profiles. I am making a JR for my small swedish open "snipa" (see my profile). The intended sail is a about 11.5 sqm, see "Rigg.pdf".

    The idea is to fasten the panels to battens, boom and yard using keder, see "Lattor.pdf". The battens will be made from two halves of 22 x 45 mm wood (pine) where a 12 mm channel is routed. A 12 x 10 mm GPR tube is glued in this channel. After gluing the two halves together, 2mm saw is used to cut the groove for the keder. All this is simply made using a home shop router and a table saw.

    A prototype panel is shown in the pictures attached.I have not yet found a solution to how to fasten the leech line to the batten ends. I will also make a practical test for the strength of the keder.

    I welcome all comments and suggestions to improvements of this suggested method of making a sail with separate panels. Should i go on?

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