Help hotdog

  • 12 Nov 2020 04:38
    Reply # 9359301 on 9327660

    The bolk heads and mast step are all cut out and will be glued in as soon as wether permits.

    Change of topic here


    Sail material...

    Again; I have a sail plan for 305 ft^2  I plan on extensive cruising and ill be in NZ for extend time.

    My experience with cloth materials comes from a background in ultralight backpacking. DCF and sill nylon fall apart after 6 months outside. The only piece of gear that I have had hold up for any amount of time is my pack made from High Density Polyethylene –HDPE) reinforced nylon.  it was a black bag witch I'm sure helped stop UV dammige. The inside of the fabric was coated with silicone witch broke down but the  rest of the material held up very well to wear and tear. It is also cheap. 10$ a yard

    I was reading about this wether max 80 and it sounds like a good fit for me. Looks like I can get it about 15$ a yard. Not cheap but not too bad. 

    Sunbrella- too expensive

    Top gun-too heavy

    Top notch 9 ??? 

    I'm thinking I'll just end up with Dacron. Unless y'all think that there is a material that would last longer that is equal or less in price.

  • 03 Nov 2020 20:57
    Reply # 9343164 on 9327660

    David!

    This sounds great! I'll do just that. I think that the mast I have ordered is straight up and down at the bottom there. (no taper) I still think this is the best way for me to accomplish this task. I would emagin that it gives me a little wiggle room when stepping the mast as well! Thanks for sticking with me through this. Very cool of ya. 


    The wedge is one of man kinds finest invention. I have picked up a 13 ton pice of concrete with nothing more then a a stack of oak wedges and a big hammer... Big hammer being the second best invention hahaha

  • 03 Nov 2020 08:25
    Reply # 9341910 on 9341413
    Jeffrey wrote:

    David!

    Thanks for clarifying. I believe I understand what you are saying ,but I drew a picture to help make sure of it. (Figure 1) I also drew a picture of my original idea just to help clear up any confusion.(figure 2). I would still like to keep a gap in between the keel and the underside of the mast steep but if you think this is not an option I can reconsider the showering with my my head out of the forward hatch. Now here in Chicago, it is hard to get my hands on any hardwood and I don't have any mill to turn it. I do have friends that would be able to make it out of aluminum though and I could have a plug made with a piece of square tube stock welded to that? Could you maybe recommend a size and thickness of tube stock? That is if you think it would be doable?

    The sketches have helped me better to understand the proportions of what you're doing. It's a very different geometry from the kind of round-ish hull section of many GRP boats.

    You're right, there is so much contact area on the sides of your plywood stack that you can afford a gap underneath it.

    We all have to work with whatever tools, materials and skills we have to hand, so if a hardwood plug is not so easy, we have to look elsewhere.

    I don't like the thought of a fabricated aluminum end plug, because I don't see how it can easily be tapered.

    So I come back to your fig. 2 sketch, but with some taper in the hole, to suit softwood wedges. What I would do is:

    1. Put in a piece of 3/4in plywood (well coated with epoxy) on edge between the two bulkheads, with its top horizontal. 
    2. Bond a piece of plywood horizontally onto this, stretching from bulkhead to bulkhead, and bonded to the hull sides. Make two large holes, either side of the vertical plywood, for cables and drains. Flow-coat this deeply with epoxy, as the tube will rest on it.
    3. Now build up the stack, maybe five layers of 3/4in plywood. The first layer to have an octagonal hole in it, 8.5in across flats. Subsequent layers to have an octagonal hole a little larger, until the top layer has an octagonal hole 8.75in across flats.
    4. Soak the end grain with neat epoxy, then fill the steps in the hole flush with epoxy filler so that there is a reasonably smooth, tapered, eight-sided hole.
    5. Make eight softwood wedges with a taper to match, 5/16in thick at the bottom, and long enough that there is something to get hold of to extract them when the mast is to be un-stepped.
    6. Add the brackets and through bar to prevent rotation and lifting.

    How does that sound?

  • 02 Nov 2020 23:55
    Reply # 9341413 on 9327660

    Graeme!

    Oh yeah! That guy is really something. I am going to use the self steering wind vane that he designed! Definitely an inspection to me. But don't fret my friend. When me David Taylor talks, I shut my mouth and lesten. And listen good too! For example...


    David!

    Thanks for clarifying. I believe I understand what you are saying ,but I drew a picture to help make sure of it. (Figure 1) I also drew a picture of my original idea just to help clear up any confusion.(figure 2). I would still like to keep a gap in between the keel and the underside of the mast steep but if you think this is not an option I can reconsider the showering with my my head out of the forward hatch. Now here in Chicago, it is hard to get my hands on any hardwood and I don't have any mill to turn it. I do have friends that would be able to make it out of aluminum though and I could have a plug made with a piece of square tube stock welded to that? Could you maybe recommend a size and thickness of tube stock? That is if you think it would be doable?

    Ueli!

    Thanks for your modesty. Davids advice is good as gold. I attached some works of art to help clear up any confusion.

    Thanks everyone for helping me through this. It's really exciting for me! Thanks a million!


    3 files
  • 02 Nov 2020 22:34
    Reply # 9341290 on 9327660

    Zane, the answer to your question is "yes"

    Jeffrey, I feel a little stupid chiming in with that previous post, but it was motivated out of concern with what I thought was your plan to to lock the mast down with thru-mast fittings at the partners. Never mind, you now have a much better analysis from David, with some very detailed advice.

    I found a series of videos (I can't find a home page) about a Contessa 26 called Wave Rover, stripped down and re-built for a circumnavigation. Seems to have been inspired by Mingming ll in one respect. Maybe you are aware of the series.




    Last modified: 02 Nov 2020 22:48 | Anonymous member
  • 02 Nov 2020 09:16
    Reply # 9339801 on 9338962
    Jeffrey wrote:

    Uele!

    I'm sold. I'm going with the 7/32" mast. There is a 6 month back order on it but it is made locally with makes me happy. Thanks so much for the advice. I was told that I need to have a 4-5 in well for the mast steep. I can only go down 3 inches below the original height of the floor. It's going to be tight getting around the 8 in mast as it is. Do you think I can get away with the 3" Barry or do I need to build it up?

    David!

    Thanks for the advice. That sounds like the easiest way to go about securing the mast. Wold you recommend a size hole for both the mast step and partner? (the mast is 8 in. OD) The mast will have fiberglass under it and I'm planning to epoxy the end grain in the wholes, but should I glass it as well? I have been told putting some Spartite into the mast step helps reduce squeaking noise. Sho I leave a little wiggle room to allow for the Spartite?

    Karl!

    I most definitely do not need my mast to rotate. I'm going to go with Davids advice on this one.why do you have yours rotate? Also, I'm planning on running my electronics through the bottom of the mast. The plan is to drill a 1 in hole down through the floor of the mast step and glue a funnel into the bottom of the mast to help direct the wire into the hole. The floor of the mast step will be floating 2 in off the keel to allow water and electric lines to move forward and aft of the boat. Also to keep standing water from contacting the plywood that the mast step is made of.

    To summarise: what you are trying to do is:

    1. to stop the mast rotating.
    2. to stop the mast heel moving from side to side.
    3. to stop the mast heel lifting.
    4. to get the electrical cables out of the mast heel conveniently.

    Item 2. is difficult with mating parallel surfaces. It's best to use wedges to fix a parallel mast into a parallel hole, or to have a tapered mast heel going into a tapered socket. My solution on Weaverbird was:

    1. to make a mast step of layers of wood and plywood, securely glassed into the hull with no air gap underneath it (important, to provide vertical support for the mast). This mast step has a roughly cut rectangular hole in it. The outside of the step is epoxy coated.
    2. to put a hardwood end plug into the bottom of the mast tube, fixed in with polyurethane sealant and having a rectangular-sectioned, tapered bottom section to match the rectangular hole in the mast step, with a gap of about 3/16in all round. This tapered end plug to be smoothly finished with epoxy and then thoroughly coated with release agent, wax and/or PVA, when the mast is stepped.
    3. After mast stepping, polyurethane casting compound was poured into that gap. It bonds to the mast step, but not to the heel of the mast.
    4. Just above the top of this hardwood end plug, there is a hole in the mast tube that both lets out the electrical cables and acts as a water drain. This is better than trying to go though the bottom of the step.
    This method prevents rotation, prevents the noise of the end of an aluminium tube grating from side to side in a loose step, and only needs the brackets and through bar to prevent lifting.

    I suggest that an 8in mast heel/step ideally has a depth of engagement of 4in, but 3in will do if space is tight. The square or rectangular tenon that I describe would have sides of about 5.5in.


    Last modified: 02 Nov 2020 12:11 | Anonymous member
  • 02 Nov 2020 08:54
    Reply # 9339764 on 9327660

    Graeme wrote:

    A very experienced ocean sailer set out from these shores some years ago - but overlooked the need to secure the mast at the heel. Unfortunately the yacht inspector who signed it off and gave him clearance over-looked it too (as he told me). The boat was lost in rough seas in the vicinity of Great Barrier Island, before even reaching deep water, due to the mast lifting off the mast step and punching through the bilge.

    This is a junk rig boat this happened to?



  • 02 Nov 2020 06:25
    Reply # 9339584 on 9327660

    Jeffrey, who said you need a 4-5" well for a mast step?

    Also, going back a couple of posts, what do you mean by "anchoring my mast to the deck step" ?

    And where does the question of "bury" arise in a mast step?

    You need the mast well fastened at the heel so it can not rotate or lift, as advised by David who described a good detail, though not necessarily the only way to do it. A very experienced ocean sailer set out from these shores some years ago - but overlooked the need to secure the mast at the heel.  Unfortunately the yacht inspector who signed it off and gave him clearance over-looked it too (as he told me). The boat was lost in rough seas in the vicinity of Great Barrier Island, before even reaching deep water, due to the mast lifting off the mast step and punching through the bilge. 

    You are not dealing with bending forces right down at the heel, only rotating and lifting/shifting laterally. This has nothing to do with "bury". You can drill and fasten at the heel (or David's better suggestion of a removeable pin together with a securely fastened housing or brackets for the pin) and it does make sense to allow for drainage if you are going to make some kind of socket. A shallow socket there in addition to th above, if you want to have "belts and braces" - provided that does not structurally compromise the keel or the mast step (as I think Ueli is reminding you). But the depth of the socket is almost irrelevant if the mast is properly fastened down and can not lift.

    The place to secure the mast against lifting and rotating is the heel, not at the deck. Here, bending forces are the issue. You need a robust structure there to provide the support needed to keep the mast upright, and the mast should be free of welds, fastenings or bolt holes at that point. This is not based on ocean cruising experience, it is simple engineering. David has offered you some good advice based on both, and it has the additional merit of being simple and practical.

    The distance between the deck structure and the heel is what is meant by "bury".

    Last modified: 02 Nov 2020 07:44 | Anonymous member
  • 02 Nov 2020 04:17
    Reply # 9339523 on 9327660

    hi jeffrey

    Jeffrey Yonkus wrote:

    Ueli!

    …I was told that I need to have a 4-5 in well for the mast steep. I can only go down 3 inches below the original height of the floor. It's going to be tight getting around the 8 in mast as it is. Do you think I can get away with the 3" Barry or do I need to build it up?

    i'm not the right guy to answer this question. i think i would build it up a little bit, but as said, there are more reliable advisors for this. (i.e. david tyler)

    The floor of the mast step will be floating 2 in off the keel to allow water and electric lines to move forward and aft of the boat.

    i wonder how you build your step. you said, you're limited in height, but you have to make the step really strong to cope with the hammering of the mast weight in a swell.

    ueli

  • 01 Nov 2020 20:32
    Reply # 9338999 on 9327660

    So!!!

    I need help picking out fabric for the sail. I have a sail plan of 305^2ft. And will be sailing across the big open ocean.

    I am ok at sewing, but haven't made anything to this scale. I will need a budget option if possible but I don't want to be doing repairs at sea all of the time. 

    I know that top gun 9 (mustang) is popular and is easier to sew then Dacron. Seems to be a bit cheaper as well. Rip stop is cheap. I was thinking of making my top panel out of something a bit heavier, as so  I can put it up during bad wether and that.

    What's the recommendation here? I'm thinking that I'll be ending up with the Dacron but it is to expensive and I feel like it is worth exploring other options! (Every dollar saved gets me that much closer to affording a hotel room.)

       " ...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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