Securing mast step wedges

  • 04 Aug 2015 12:12
    Reply # 3463962 on 3458179

    I'm a bit reluctant to hammer my step wedges in with too much gusto as I know I'll need to remove them whenever I unstep the mast, and the type of step I've built doesn't allow for tapping the wedges upwards from beneath. I've glued and screwed small rectangles of 6mm solid GRP just below the top of each step wedge so hopefully I'll be able to lever the wedges upwards when the time comes to remove them.

    Also I spent 2 days of shoulder wrecking work, cutting out, then tapering, beveling and profiling with a block plane, then sanding my set of 44 wedges, so I'm keen to avoid destroying them if possible :-) I can now see why people use Spartite!

    As the mast is aluminium I'm not too keen on using screws to secure the wooden wedges in position so I'll probably just clamp a strip of neoprene or suchlike under a long hose clamp around the mast to prevent the step wedges working loose. The mast will be held down in the normal way with a pin passing through the mast held down by brackets attached to the step. Rather than using pieces of angle for the brackets I've epoxy bonded lengths of 8mm threaded stainless rod deeply into the plywood step and used 60mm x 28mm saddles of 15mm thick Tufnol to bridge each pair of rods. These saddles are clamped down with nyloc nuts and allow a small amount of upward adjustment whilst preventing the mast from rotating.

    In my haste I'd dipped my set of wedges in clear wood preservative prior to reading David Webb's warning about incompatibility with aluminium. After some rather concerned reading up on the subject I'm reasonably sure the type of preservative I've used is safe as it contains no metals like copper, and the data sheet says the only active ingredients are fungicides like Permethrin. To be on the safe side though I've liberally coated the wedges with the same wax (Autoglym Liquid Hard Wax) I used to coat my bare aluminium mast. So they now have a decent barrier coat plus a little extra lubrication.

  • 03 Aug 2015 01:13
    Reply # 3461912 on 3458179
    I just dribbled some Gorilla glue around them once they were set in.  If they have to come out, it will probably destroy the wedges, but I doubt it will stick that well to the alloy.  I don't think you need to worry about rot: the air can easily get to them from underneath and up the narrow gaps between the wedges.
  • 01 Aug 2015 11:10
    Reply # 3460266 on 3458179

    Hi,

    one thing to be careful of is that wood preservatives can have a chemical reaction with aluminium, so this may not be an option for you.

    I used the mast band option on Arcadian before changing to a rubber sleeve and epoxy fill. and this worked well.

    Last modified: 01 Aug 2015 11:12 | Anonymous member
  • 31 Jul 2015 05:21
    Reply # 3458521 on 3458179
    Deleted user

    There will no doubt be a variety of opinions on this but some of my experience: - I have found that the wedges on my yacht do not work loose at all but to achieve this I hammered them well home on several occasions with a 3lb hammer. There was the initial set up of the mast and then after a couple of weeks of sailing I pounded them home again. The wood that my wedges are made of are I would say of medium hardness, not super soft but not hard either. If I was going to secure my wedges in position I think I would prefer to use a small screw through the wedge into the mast, this would be the tidiest and most secure way of doing it.

    Re treating the wood, I think there would be a number of options from just plain painting, coating with thinned epoxy resin which will soak into the wood a little way, or using oil such as you mentioned, either Linseed or some other oil. I have had very good results with Danish oil on my timber kitchen bench tops in my house, it seems to stand up to moisture better than Linseed oil. Once again I think I would allow the oil to really penetrate into the wood, although on Footprints the wedges are not treated at all and after 18 years there is no sign of deterioration, which probably says a lot for the potential durability of mast wedges.

    I have posted a photo in the Technical Forum illustrations of the wedges in place on my yacht.

    Last modified: 31 Jul 2015 10:26 | Deleted user
  • 30 Jul 2015 21:51
    Message # 3458179

    Is there a preferred way to stop wooden mast step wedges riding up and working loose? The method of attaching small plywood squares to the below deck side of mast partner wedges obviously can't be used with mast step wedges, so I imagine some sort of band clamp either around the wedges themselves, or around the mast just above the wedge tops would be one solution. My mast step and set of 22 wedges have a 1 in 50 taper, the step is layered ply, heavily epoxied, and the mast is a 222mm aluminium lighting pole that's parallel from base to well above the partners.

    Also what treatment, if any, should softwood wedges receive....... soaking in wood preservative, linseed oil etc, or just left bare? I suspect being buried in a mast step or under a sealed mast boot might be ideal for rot to take hold unseen.

    Last modified: 30 Jul 2015 21:55 | Anonymous member
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