What core?

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madaz
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Location: Hobart, Tasmania

What core?

Post by madaz » Sun Jul 19, 2009 11:01 pm

Gday David, Polycore seems like a pretty good material, as you say it is unproven but it seems like it could be good. I would be very interested in build photos when you start, if you can take some snaps and start your own thread in members multis.

gunnadoo
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Location: Innisfail Qld

What core?

Post by gunnadoo » Mon Jul 20, 2009 12:44 am

David is correct in the guidance to information re polycore, although I see that the name has been changed to Polycore Composites. And yes, the polypipe I was referring to is common or garden variety :D (it really is) plumbing pipe. David, good on you for having a go - the kit looks great! I possibly overbuilt FUB (fairly ugly boat), but it is getting used hard, and standing up well. I used split 90 mm stormwater pipe as stringers between the floor and bottom (would have been lighter with poly core edge mounted), and as reinforcement - just run 50mm pipe over the tablesaw, remove 10 mm, sand, place over the edge of 10 mm polycore, glass. I may be wrong, but I see this stuff as out plying plywood, as soon as we can get designers on side. Cheaper, lighter, as close to unsinkable as you can get - and no rot (gee I love that). I do not wish to go down the kit road, and am almost at the point where I am going to stick my neck out and do my own design - not that I mind paying, just that I have not been able to find a designer who has anything in the material. Cheers all.

Finally
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Location: Cairns

What core?

Post by Finally » Mon Jul 20, 2009 4:34 am

Thanks all.



It took me a while to take the leap of faith with an unproven material in boat construction. I suppose my visit to SCIB show in 2008, when Pacific Multihulls had a stand, swayed me. To actually touch and feel the product and talk to the designer (though they have a vested interest). Originally they were going down the path of polycore for the hull shoes as well (they had made up a cross-section of part of the hull for their display). Can't remember the reason why but they changed to HD foam for the hull shoes. I'd have to look at the data to see where foam is superior to polycore - I vaguely remember that HD foam had superior compression qualities than polycore for this part of the build.



I have gone with the option of havng the hull shoes delivered in one piece rather than cut in half, as they would normally do to have the kit fit inside a 20' container.



I went for a visit to the factory in Coffs Harbour about 3 weeks ago when they were laying up some of my polycore laminate. Speaking to them, they are pretty confident that the all up "dry" weight will come pretty close to the planned 3.8T - some of this will be dependant on the layup weights applied by the builder.



Jim - I'm a bit of a hoon when it comes to sailing and I liked the "power to weight ratio" of this design (amongst many other things I considered) and still cater for my need for a cruising live aboard. Though I have slowed down with age, I still would like a boat with a bit of a turn for speed.



Gunnadoo - boat designs are always a bit of a compromise. Even with the P40 kit, I'll be making some changes to suit my individual needs and even then I am going to live with certain other things in the design that I'm not 100% happy with. I'll put up with them because changing them will create a whole lot of other issues. Overall, however, the kit was the closest to what I was looking for - in layout, volume, materials used, weight (and therefore payload) and construction methodology. The CNC panels are quite large - for instance each chamfer panel is just two pieces which, hopefully, will cut down on the dreaded fairing time. I have found the designer (Mark Stephens) quite approachable and the plans I have already received (and studied til I can almost recite them verbatim) are quite detailed.



Madaz - I will be taking photos, if nothing else for my own enjoyment to look back on and say "I did that".



I've now reached a stage that I am now anxiously waiting the arrival of the kit - the sooner I can start, the sooner I can finish and the sooner I can finish the sooner I can enjoy the cruising life on my own boat.



David

Chrisg
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What core?

Post by Chrisg » Fri Mar 12, 2010 8:00 am

All the discussion is fine about balsa vs foam and poly core but what happened to good old marine ply. So it is heavier but not by that much, its cheaper than the modern day composite materials which makes it more affordable to those dreaming. Do those of you have used ply and are now sailing ever regret the decission to build with epoxy of ply?



Chris
Chris & Michelle

Outback Dreamer - Sarah 23
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puremajek
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What core?

Post by puremajek » Sat Mar 13, 2010 12:05 am

Hi Chris,

Budget, performance and 'cruiser style' are three areas that everyone with argue about until the cows come home, everyone trying to justify their own choice and expense. Just looking at the amateur building industry should provide your answer. The amount of yachts being built by amateurs with ply and to some extent, with one particular core, should help. 9 times out of 10, budget has forced the decision.



Having said this, we have never regretted ply. I know no different.
James
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Smooth Cruiser
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What core?

Post by Smooth Cruiser » Sat Mar 13, 2010 7:15 pm

It has to be recognised that ply has an age limit, and this - combined with the fact that ply is most often the material of choice for the amateur builder - is what means that the resale value of ply boats will be less. A good ply build will still be better than a bad foam / glass / core build though - and vice versa.



A big advantage of ply is that repair is also straight forward - so even if there is a bit of rot in a particular spot, it can be cut out and repaired very easily.



At the end of the day anything in boating is always about finding the best compromise for each person between a myriad of variables, price being one of the biggest - and ply has a massive advantage here to help influence the decision!



Of course there are very real advantages and disadvantages to be considered when selecting construction materials, and the issue can be hotly argued or discussed at length - but I have found after 7 years of sailing a ply boat that when I am sitting in a beuatiful remote anchorage alongside a glass boat and a steel boat enjoying a quiet sundowner after a perfect days sail, there isn't too much to argue about any more. At the end of the day any well built boat will do the same thing - which is to get you out on the water enjoying it. If a ply boat lets you get out there living the dream sooner rather than slaving away for extra years saving the extra money for a more expensive material, then this has to count for a fair bit.



My honest answer to the question - any regrets with ply is no, because having a ply boat has let me get into a better suited boat for cruising earlier than I otherwise would have been able to.



Would I rather own a ply boat or a glass / foam / balsa boat? The answer would be that I would rather own glass / core / balsa. But I couldn't buy a glass / core / balsa boat with the fittings and features that mine has for anywhere near the same price, so for me the compromise was ply and I have enjoyed being out there sailing! 8)

Jim
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What core?

Post by Jim » Mon Mar 15, 2010 5:08 am

I second all that.

Jim.

Chrisg
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What core?

Post by Chrisg » Mon Mar 15, 2010 6:57 am

The comments above by smooth are precisely those of my inner thoughts yet I could not have expressed them as well as smooth did. :D



Within this forum I looked at the topic "Anchorages or just great spots" and then at "Coongul Crk, Fraser Island" and wonder if the Easy Sarah could have entered that estury, and if not would I be resticting possible options.



At this stage te way I am thinking is a ply boat (Easy - Sarah) with mini keels vs an Oram 39C with a dagger board. :?: :?:

The decission is mine!



Chris
Chris & Michelle

Outback Dreamer - Sarah 23
http://www.outbackdreamer.com

puremajek
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What core?

Post by puremajek » Wed Mar 24, 2010 2:39 am

Chris

Peter S is coming sailing up the coast with me in a few days. I'll ask and get back.
James
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Chrisg
Posts: 141
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Location: Country Victoria

What core?

Post by Chrisg » Wed Mar 24, 2010 4:10 am

James, We spent 4 hours with Peter and Ann last last Saturday on their Easy Sarah and whilst that specific location was not stated we did discuss entry into shallow inlets, and the pro's and cons of mini keels vs dagger baords plus everything else associated with the Sarah. By the end of this week will make a decision on what to build and then get on with it.



I'd still be interested to hear what Peter says about Coongul Crk, Fraser Island so please do ask.



Chris
Chris & Michelle

Outback Dreamer - Sarah 23
http://www.outbackdreamer.com

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