• 29 May 2024 09:04
    Reply # 13363015 on 13349020

    Hi Graeme,

    I don't think that the alu plate is needed for structural integrity, that thick grp is strong enough by far.

    Why the extra nuts in between? These nuts are actually fastening the eyebolts to the masthead. The alu plate is then mounted on top and fixated with the second nuts.

    Why the gap betwen alu plate and grp? That way, I can take of the plate to drill and mount stuff, like i.e. the windex. The mounted stuff can then be mounted to the alu plate only. However, all these words seem to make not much sense to me... just have a look at the foto attached ;-)



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  • 27 May 2024 21:40
    Reply # 13362278 on 13349020
    Anonymous member (Administrator)

    Excellent: a solution to a home-made fitting for a tapered mast top.

    The aluminium plate is easy to make too, and I think it is essential, though I don't understand why it is separated from the fibreglass by the extra nuts.

    Last modified: 27 May 2024 22:01 | Anonymous member (Administrator)
  • 27 May 2024 18:21
    Reply # 13362212 on 13349020

    Good evening,

    probably Robert already finished his masthead long ago. Still, I want to add my example of a grp masthead, at least for the record. It laminated to about 5 mm thickness. The pretty much exact fit to the conical mast top I gained by wrapping one layer of cardboard around the mast top, then one layer of thin plastic foil from the usual kitchen supply (doesn't stick to epoxy). This I used as the form, laminated 3 layers on top, removed it, cut it to length, double checked the fit on the actual clean mast top, and added the rest of the layers. Though probably heavily overbuilt, it was simple, pretty straight forward and fitted snuggly in the end (just glued onto the mast with MS-Polymer/Pantera). The alu plate is not really needed, I just added it to have a "gear carrier" which lets me mount stuff without drilling through the grp.


    8 files
  • 24 May 2024 22:44
    Reply # 13361604 on 13349020
    Anonymous member (Administrator)


    Roger modified Mingming mast head.

    He fixed the new mast head by using as support the previous Ushape riveted platine.


    5 files
  • 12 May 2024 07:42
    Reply # 13355611 on 13352599
    Tapatya's as posted by Kevin.

    Perhaps I should add that this is a depiction of my basic mast head fittings. The foreward one has the VHF antenna fitted on top of it (completely watertight), the main mast fitting has the anchor and steaming light fitted directly on top of it (again watertight). The cable for the top light exits through a cable gland on the side under the top disc. This has all been quite successful and was really quite easy to fabricate. The masts both have a 25mm square hole up the middle where the cables run.
  • 05 May 2024 23:01
    Reply # 13352599 on 13349020
    Anonymous member (Administrator)

    Frank: the first two of your links did not work - presumably they are links to your own photo gallery. There is a little quirk of our website, which comes up from time to time: You need to open a second instance of the JRA website and instead of going to your "view profile" and from there to your "member photo albums" (which are viewable only by you) - instead you need to go to your "My directory profile" and access your photo links from there. The links from "My directory profile" are different, and will lead to results which are viewable to other members.

    Clear as mud?

    Alternatively, you can go to your  "View profile" then to your "member photo album", access the photo and copy and paste it into your post - but (for the benefit of other readers) you need to grab the "handles" and size the photo to about 2/3 of the viewing screen width in order to avoid another quirk of our website (if you don't, the accompanying text will be forced outside of the viewing area.)

    Here are Frank's two photographs:

    To add to Frank's useful post, may I add:

    1. Arne has an aluminium fabricated masthead detail in one of his writings, similar to the de-lux fitting shown above, and to Tapatya's as posted by Kevin.

    2, Paul Th has shown a quite different and very practical type of masthead crane (a cross tube) for the masts he makes.

    3. The most sophisticated idea on record is the masthead fitting on Ted's Fly which was reported to be engineered to allow rotation, so the halyard spans and lifts can rotate with the sail. "...swivelling cone(s) on acetal bearing(s)..." (Ref JRA magazine #88)

    The common factor to all of these is that the masthead blocks are craned out,  so they can hang vertically. This seems to be essential and ought be be obvious. I am sure Frank already knows this, but I add this note for the benefit of mistake-prone people like me, and dinghy sailers thinking of converting to junk rig.  The first masthead fitting I made was only a for a small boat so I didn't bother about the need for a crane. I just fastened the blocks to the masthead by using saddles attached vertically to the walls of the mast.

    It was a failure because the blocks did not hang vertically, which put a lot of friction on the halyard - the problem was immediately obvious and that otherwise nice and simple idea had to be scrapped. I mention this because I observe that I am not the only one who has made this mistake. Note: the saddle shown here is the problem.

    Evidently the U-bolts used by David T and shown in the second of the three photos given by Frank (see below), are a different shape and do act as cranes, allowing the blocks to hang vertically. This detail is not quite as simple as it looks.

    For a small boat, dinghy etc, the plywood disk type of crane (as shown in the third of Frank's three photos) is a nice and simple detail which is what I settled for, as it works well and you can make it yourself using little U-bolts or saddles. 

    It is bolted to a decent plug in the top of the mast, and is fixed against rotation. - simple if the masthead is an untapered tube - likewise simple if the masthead is solid. Perhaps not so suitable for a larger boat, or a tapered masthead tube.

    I must say, I am impressed by Annie's ingenious disk crane with webbing tangs

    Last modified: 07 May 2024 22:43 | Anonymous member (Administrator)
  • 05 May 2024 21:35
    Reply # 13352568 on 13349020
    Anonymous wrote:

    I am working on a 24' Bayliner Buccaneer and have my mast all sorted out. I am about to begin fabrication of the masthead and would like to see pics of how others have done it. I've been working from two books, Practical Junk Rig & Design & build your own Junk rig. Any pics would be appreciated, thank you.

    Here is the one a friend welded for me some years ago:

    The way Annie built one for FanShi:

    And 3 pictures from other JRA members attached.

    3 files
    Last modified: 05 May 2024 21:37 | Anonymous member
  • 28 Apr 2024 07:59
    Reply # 13349130 on 13349020

    Thanks Kevin 

  • 27 Apr 2024 21:38
    Reply # 13349055 on 13349020
    Anonymous member (Administrator)

    There are picture/diagrams on Flickr of the SV Tapatya masthead

    see and 

  • 27 Apr 2024 19:59
    Message # 13349020

    I am working on a 24' Bayliner Buccaneer and have my mast all sorted out. I am about to begin fabrication of the masthead and would like to see pics of how others have done it. I've been working from two books, Practical Junk Rig & Design & build your own Junk rig. Any pics would be appreciated, thank you.

       " ...there is nothing - absolutely nothing - half so much worth doing as simply messing about in junk-rigged boats" 
                                                               - the Chinese Water Rat

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