Moon River build update

  • 24 Aug 2017 14:08
    Reply # 5045341 on 5044313
    Scott Dufour wrote:

    It's a good 2 cents, David.

    Regarding the structural bulkheads:  The original main structural bulkheads were right were you indicated.  But I cut out the middle one - to which the chainplates were attached, and effectively moved it forward to where my mast is now. So there is a larger un-bulkheaded distance between it and the companionway bulkhead.  Would it make sense for me to take advantage of this galley bulkhead as a half - structure and extend it into the bilge as shown in the photo?   If that's the case, then perhaps 3/4" isn't too much.  On other hand, it is not that far from the bridge deck bulkhead (5 feet, maybe), and might not be that much help to the sturcture. The head's bulkhead on the port side is slightly aft of the galley bulkhead, and doesn't reach into the bilge, but serves perhaps the other side of the hull in a similar way. 

    I should add that in the original design, no bulkhead went into the bilge - they all tabbed to the hull sides, and sat on a liner that spanned the entire sole area.  The lack of liner makes me happy - everywhere's accessible.  But it's also got me worried.  It is quite difficult to determine exactly what strength it gave the hull and where. I don't know, for instance, how much longitudinal stiffness it imparted and whether I should add stringers to make up for it.

    The question, then, is what is spreading the loadings from the keel, both sideways and fore and aft, around the bottom of the hull? I would expect to see some top-hat-style floors athwartships, or something of the kind. Was the liner doing that job, I wonder? So long as the keel is well supported, I wouldn't be too concerned about the bulkheads. One of the important functions of the midships bulkhead was to carry the shroud load from the chainplates down to the mast heel, and that's no longer relevant.
  • 23 Aug 2017 22:34
    Reply # 5044526 on 5043963
    Scott Dufour wrote:The forward leg will get the deep sink, draining to a tank in the bilge with a manual pump out.  The outlet will be in the transom above the waterline.  The sink location is right about where the white papered plywood sits in this mockup.  (The glassed-in aft galley/starboard bridgedeck is visible in the way back.)
    This seems a tad complicated to me, Scott.  There is the risk of food debris not getting thoroughly flushed out and starting to smell.  Why not just fit a pump in the galley and send it out sideways?  You've got piping either way, which is a nuisance, but that from the sink pump could possibly be routed under a shelf. 

    Is the bottom of the sink below the waterline?  If not, an alternative is a simple standpipe down through the bottom of the boat.  Done properly, this is structurally sound, simple and fool proof.  David Tyler has fitted them in both wooden and fibreglass boats.

    Make sure that your floor hatches are big enough.  Easiest is just to screw down the cabin sole boards, really.  Four screws undone and perfect access.

  • 23 Aug 2017 19:23
    Reply # 5044313 on 5008877
    Deleted user

    It's a good 2 cents, David.

    Regarding the structural bulkheads:  The original main structural bulkheads were right were you indicated.  But I cut out the middle one - to which the chainplates were attached, and effectively moved it forward to where my mast is now. So there is a larger un-bulkheaded distance between it and the companionway bulkhead.  Would it make sense for me to take advantage of this galley bulkhead as a half - structure and extend it into the bilge as shown in the photo?   If that's the case, then perhaps 3/4" isn't too much.  On other hand, it is not that far from the bridge deck bulkhead (5 feet, maybe), and might not be that much help to the structure. The head's bulkhead on the port side is slightly aft of the galley bulkhead, and doesn't reach into the bilge, but serves perhaps the other side of the hull in a similar way. 

    I should add that in the original design, no bulkhead went into the bilge - they all tabbed to the hull sides, and sat on a liner that spanned the entire sole area.  The lack of liner makes me happy - everywhere's accessible.  But it's also got me worried.  It is quite difficult to determine exactly what strength it gave the hull and where. I don't know, for instance, how much longitudinal stiffness it imparted and whether I should add stringers to make up for it.

    Last modified: 28 Aug 2017 14:15 | Deleted user
  • 23 Aug 2017 17:47
    Reply # 5044108 on 5008877

    My 2 cents worth:

    Only the main structural bulkheads, the ones that impart stiffness to the hull, should go down to meet the hull under the sole. Those would normally be at the companionway, amidships, and forward near the mast.

    Then the margins of the cabin sole go down, giving drier lockers with a flat bottom.

    Then the secondary bulkheads and the plinths of the furniture go in on top of the sole, keeping them out of the possible dampness under the sole.

    The cabin sole itself might well be in three parts: a central fixed part in way of the table, and two boards that can be lifted, with catches to hold them down.

    3/4" is a bit much for secondary bulkheads, assuming that they have counter tops etc attached to them at a level not far from the top to stiffen them. How about using 1/2" ply and adding 1/4" teak faced ply above the counter tops only, so that your teak mouldings fit?

  • 23 Aug 2017 16:40
    Reply # 5043963 on 5008877
    Deleted user

    Some more progress, though not very visible.  The aft galley/starboard bridgedeck bulkhead is now glassed in on both fore and aft sides, as is the head's forward bulkhead.


    I had been thinking that I'd put an athwarship gimballed stovetop on the forward leg of the U shaped galley, but wiser minds on this forum convinced me that the gimballing isn't necessary.  That allows me to put the stovetop on the opposite, aft leg of the galley, close to the companion way to let out the heat and any smoke. The forward leg will get the deep sink, draining to a tank in the bilge with a manual pump out.  The outlet will be in the transom above the waterline.  The sink location is right about where the white papered plywood sits in this mockup.  (The glassed-in aft galley/starboard bridgedeck is visible in the way back.)


    And that locates the forward galley bulkhead where you see in the two shape grabs below.



    So here's a question for all you experienced hands:

    This bulkhead extends down into the rather shallow bilge - definitely below the sole.  Should I put the bulkhead all the way down to its inboard end, or should the sole go down first and the bottom of the bulkhead stop at the top of the sole?  

    Which leads to the whole question of sole design.  I'm thinking glassed in only at the edges, large portions screwed down to those with access holes/hatches cut in at the various obvious places.  Regular access is through the hatches, but I'd like to be able to take the whole sole up without an angle grinder or saw if need be.  What are people's thoughts about that?

    I'd like to make that galley bulkhead corner cap, the one that sticks out to almost the centerline, a handhold like the one shown below.


    This piece, which is teak, is only available for 3/4" plywood bulkheads. That is a bit of overkill for the bulkhead, but perhaps appropriate for throwing weight against. This also asthetically locks me into teak endcaps for everything on the boat, which is what I was planning anyway.  What are some opinions on the 3/4" size of this bulkhead, or even the use of these combo handholds end caps?  Too much weight for not enough benefit?  A smart choice?

    Last modified: 23 Aug 2017 16:49 | Deleted user
  • 18 Aug 2017 13:45
    Reply # 5035258 on 5008877
    Deleted user

    where you save the money /time is the no blush wax and the fact that for me personally i have no skin problems with MAS because of its castor oil base and favouritete is the longer pot life that we get here.

    One thing i should point out is that MAS is very forgiving but to get the very best out of it the resin should be clear with no clouding if it has some clouding heat it up let it cool and its ready to go again.



  • 17 Aug 2017 18:38
    Reply # 5034112 on 5032835
    Deleted user
    peter johnson wrote:

    Scott hi 


    I am a MAS distributor here in the UK covering the EU 

    MAS is probably the best epoxy on the market and yes it is more expensive than others you will save so much time and labour using it compared with west and others.

    Now some good new MAS do a boat building epoxy it's a 5 to 1 mix the same as west you can use the same additives as any other epoxy and it's been priced to be cheaper than west

    Get your stockest to sort you some out failing that let me know and I will see if I can find a dealer on our network who can help you out

    Ask for it as traditional or boat building epoxy

    pete j 

     black bear boating and leisure

    Hi Peter,

    Thank you for the input.  I don't particularly like the 5 to 1 ratio epoxies - they have less room for error in the mix.

    I'm also bit skeptical about the claim that I would save time and labor using MAS vs RAKA. I'm making the same motions, the same mixing, the same... well, everything.  Perhaps MAS wets out fiberglass cloth a bit quicker; it does have a great viscosity and capillary action. But I can't imagine that would offset a doubled price.  

    Perhaps I'm missing something? 

    Last modified: 17 Aug 2017 18:45 | Deleted user
  • 16 Aug 2017 20:38
    Reply # 5032835 on 5008877
    Deleted user

    Scott hi 


    I am a MAS distributor here in the UK covering the EU 

    MAS is probably the best epoxy on the market and yes it is more expensive than others you will save so much time and labour using it compared with west and others.

    Now some good new MAS do a boat building epoxy it's a 5 to 1 mix the same as west you can use the same additives as any other epoxy and it's been priced to be cheaper than west

    Get your stockest to sort you some out failing that let me know and I will see if I can find a dealer on our network who can help you out

    Ask for it as traditional or boat building epoxy

    pete j 

     black bear boating and leisure

    Last modified: 16 Aug 2017 20:39 | Deleted user
  • 16 Aug 2017 14:59
    Reply # 5032281 on 5008877
    Deleted user

    Thanks, Annie.

    West is about the same price as the MAS.  But the RAKA I just ordered, was indeed $498 for 9 gallons (6 gal. resin, 3 gal hardener), plus about $60 shipping from Florida to Connecticut - about 1200 miles.  They have a variety of resins and hardeners to choose from, and I got standard resin and the special non-blushing hardener.  MAS has spoiled me a bit and I avoid the extra step of washing off the amine blush, so it's worth the extra $45 to me.  It's not laziness per se, but that I work in a pretty non-linear manner, and I will certainly forget to wash the blush off and ruin large sections otherwise.

    Last modified: 16 Aug 2017 15:01 | Deleted user
  • 15 Aug 2017 23:15
    Reply # 5031387 on 5028551
    Scott Dufour wrote:I'm also going through epoxy at an alarming rate - almost 4 gallons in just a few weeks. I'm pretty frugal with it, too; I'm certainly not over-saturating the glass. It's MAS Epoxy. I can get it locally at Defender Marine in Connecticut for $439 per five gallons of resin, and another $400 for the 2.5 gallons of hardener that goes with it.

    It's a conundrum: when I'm not able to make progress on the boat, it feels awful.  And when I am making progress on the boat... Oh! The expense!

    Gosh, that sounds like expensive epoxy.  I've always found things a lot cheaper in USA.  I'm spending US$335 for 24 litres, which is 6 US gallons - US$419 for 7.5 gallons.  I'm using WEST.  I know we all have our preferences, but would WEST be more affordable?

    You're making great progress!


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