Home Forums Forum Mast Raising – FRP Boat

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    • #51287
      MalcolmD
      Spectator

      Hi all. I’m an OAP sailer and I’ve owned my boat for a year now and had the mast up and down a few times. Ive read the excellent article on mast raising and tried the method whereby you stand in the boat and do the vertical mast lift in two. Although I can just about manage it on my own, I’m finding the process rather stressful and precarious. Has anybody devised any other method? Perhaps using an A frame or the like? Obviously the centreboard housing is somewhat in the way of a classical mast raising method, but I wonder if anyone has devised a way around that? With thanks. Malcolm D.

    • #51298
      Oliver Shaw
      Moderator

      Since I wrote the article – and thank you for the complimentary comment – I haven’t much to add that isn’t already in the article, except that I have very occasionally heard of individuals who have set up A-frame systems. But I have no details of those; if I were to set one up I would be designing from scratch.

      Oliver

    • #51299
      MalcolmD
      Spectator

      Oliver. Thanks for your reply. I’ve built a number of lifting devices in the past for more conventional trailer sailers I’ve owned. I’m putting together a lifting rig for the GP14. If it goes well, I’ll post some details here.

    • #51300
      Oliver Shaw
      Moderator

      I suggest that by far the easiest solution is to arrange for an assistant to help you control the mast and to keep it vertical as the two of you lift it. At our age there is nothing at all wrong with borrowing a bit of assistance when needed; and of course if you sail with a crew then (if he or she is older and larger than merely a child) you already have the assistance available.

      Otherwise, some very preliminary design thoughts for a lifting system:

      For any type of lifting arrangement probably the largest difficulty would be controlling the heel of the mast during the lift, without a tabernacle or other fixed pivot point. At the start of the lift there would be a significant force trying to push the heel forwards into the bow buoyancy. It is that very specific problem that led me to reject lifting systems, and develop my technique.

      However if you do wish to develop a lifting system, possibly the forestay might perhaps be used as the lifting line, with a pivoting A-frame; A-frame vertical at the start of the lift and almost lying (forwards) on the foredeck by the end of the lift. The pivot points would need to be secured in some way; perhaps hinged to a temporary flat plate over the shroud holes in the side decks, with bolt and wing nut (and plate underneath) to temporarily hold them in place.

      Otherwise, using a separate line (other than the forestay) as the lifting line, one obvious consideration is how to remove the lifting line once the mast is raised. Note that the attachment point is going to be out of reach, way above head height.

      The centre of gravity of the rigged metal mast is approximately at spreader height.

      As an alternative to the above pivoting A-frame, if a fixed vertical A-frame or tripod or other temporary structure were set up, in line with or possibly just forward of the mast gate, with the lifting point higher than the spreader height, a lifting line could perhaps be temporarily attached by means of a simple strop (along the lines of a miniaturised helicopter strop) around the mast just below the spreader, and with a downhaul attached. When the mast has been pulled vertical, that lifting line would then be released, and the strop lowered to deck level (using the downhaul if necessary) and unhooked.

      If one is standing inside the boat, with a bit of ingenuity it might be possible to arrange such a system to lift the mast to a vertical position standing on the cockpit floor, forward, to one side of the centreboard case. Then, with the lifting strop removed, and keeping the mast vertical all the time, it is a relatively easy job to lift the mast bodily sideways and forwards into its correct position.

      This would still require you to get inside the boat, so you would need to be adequately satisfied that the boat is strong enough and sufficiently well supported to take your weight.

      However I have never attempted to set up such a system, as I feel that even when built it would have its own challenges in operating it, and I would expect it to be stressful and precarious. An additional consideration for myself was that this would seem to have far too much potential for damaging my carefully nurtured varnish. Up to the point where I retired from single-handing GP14s, at age 80, after a small handful of age-related close calls, I felt safer doing the job my way; but of course, it is easier and less precarious if you have an assistant.

      Oliver

    • #51301
      MalcolmD
      Spectator

      Hi Oliver,

      Thank you very much for giving this some thought. Its useful to hear your comments and ideas.

      I’ve built similar systems using the first method you suggested, for both my Challenger Micro 18 and the sailing version of the McGregor 26. I’ve used both a single strut method and an A Frame method. The A Frame works much better. The problem with this method for the GP14 is that the mast foot cannot rest in it’s final position and must be subsequently manoeuvred into position. So I don’t want to raise the mast adjacent to its final position and have the problem of it being attached by it’s forestay or shrouds.

      I think the problem is more akin to a keel stepped mast situation.

      One solution with keel stepped masts is to lift them horizontally at their centre of gravity and then rotate them 90 degrees and lower them into position. The problem with that solution would be that the temporary mast is as unwealdy to set up as the actual mast.

      I think the solution here is to use a version of your second solution, mounting it, as you suggest, just forward of the mast gate. Again, too tall a temporary mast and you are back to square one. However I think I can get away with a pole a little shorter than the distance to the spreaders. I have an extra .5m to the mast foot position. I can use the normal forestay and spreader mounts. I can be standing in the boat, near the mast gate and use a strop with pulley system, as you suggest, to lift the mast from the rear of the boat to a vertical position, adjacent to its final position. The nuisance part, as you alluded too, is control of the position of the strop at the beginning and end of the lift. However, if I lift from the around the spreader, I should have maximum control for minimum effort. I may even be able to use my own foot to hold the mast foot in position The good bit is that, once vertical, the mast can not only be lifted relatively easily into position, but the weight is supported if necessary too.

      There are a few other details like a temporary step in the bottom of the boat. The boat itself seems to be happy to take my weight and I think the deck around the mast gate is sufficiently sturdy.

      Will this arrangement be as stressful and precarious? Possibly. I hope not. It’s certainly a familiar one to me which should help. One advantage may be that the mast can be raised in all weather conditions.

      Fingers crossed. I’ll let you know how it goes and how it feels. With thanks. Malcolm

    • #51302
      MalcolmD
      Spectator

      Ps. Any further thoughts or suggestions gratefully received.

    • #51303
      Oliver Shaw
      Moderator

      I think the biggest problem is likely to be control of the mast foot.

      But if you manage to devise a system which works well it could potentially be useful to other members. If you succeed, if you like to then write it up, with photos, we can publish it, either on the website or in Mainsail (and/or the e-News) or both.

      Oliver

    • #51304
      MalcolmD
      Spectator

      Thanks Oliver. I’m just figuring out lateral stability of the mast as it rises with a little help from ChatGPT.

    • #51305
      Oliver Shaw
      Moderator

      Lateral stability: for what it is worth, I have a well-developed mast-raising technique on my Privateer 20 trailer-sailer gaff cutter.

      The mast is stepped on deck, in a substantial tabernacle.

      I use just a single strut placed on the mast near its base, with jaws to locate it; I secure the inner forestay to the outer end of the strut, and re-purpose the mainsheet tackle between the end of the strut and the stemhead. The tackle is rove to advantage, so the hauling part (the part of the rope that I pull on) comes from the upper end of the tackle.

      Initially I used lateral guys to ensure lateral stability, but very quickly found that they were redundant; so much so that I have now taken them off the rig altogether. I find that I have ample lateral control by simply moving the hauling part slightly sideways; that instantly corrects any misalignment of the mast, which is vastly heavier than that of a GP14, and about the same length.

      Good luck!

      Oliver

    • #51306
      MalcolmD
      Spectator

      Thanks..I do wonder if lateral baby stays are unnecessary, especially as I will standing in just the right position. I can see that having a strong tabernacle on the Privateer must be helpful too.

    • #51307
      MalcolmD
      Spectator

      Sadly ChatGPT seems to be a complete failure with 3D geometry!

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    • #51309
      Oliver Shaw
      Moderator

      That somewhat “interesting” arrangement, produced by AI, reminds me of the old saying that “a camel is a horse designed by a committee”!

      Oliver

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