List of Construction types/materials

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Mick@itc
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Location: Melbourne Aust

List of Construction types/materials

Post by Mick@itc » Fri Jul 15, 2011 7:01 pm

Hi all

This thread is trying to gather the different construction types/materials that are common for DIY boat building. In order to limit the list let's say that we are talking about typical construction material combinations for a 30~60 foot boat DIY projects (mono or multi). As an example let me start with the example of the duflex "Oram" type construction being used by SCRUMBLE at the moment. That seems to be panels of duflex (balsa end grain sandwiched in epoxy resin) which is then reinforced at joints with glass and epoxy. Fairings filler and high build finishes of the shape with top coat painting finishing this off.
So there is my example of the layers/lamenates involved...let's call that one the duflex material construction. Would like you guys to specify other construction materials so that we can build up the list. Don't talk about quality just yet. I am going to start a quality thread after we develop the list.

Thanks in advance.

Mick
Mick
If all you have is a hammer...everything is a nail!

sea_bee
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Location: Pillar Valley NSW

Re: List of Construction types/materials

Post by sea_bee » Sat Jul 16, 2011 2:12 pm

For DIY multis, the choice of materials is surely limited to this (unordered) list:
  • Duflex
    Foam Core
    Plywood
    Strip/West System
Anything else would be just too heavy for a multi.

For a mono, where weight does not matter, you could add
  • Steel
    Aluminium
    Carvel
to the list.

While I offer these materials as options, I would not consider most of them as viable for one reason or another. But more on that later.

Finally
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Location: Cairns

Re: List of Construction types/materials

Post by Finally » Sat Jul 16, 2011 2:31 pm

"For DIY multis, the choice of materials is surely limited to this (unordered) list:
  • Duflex
    Foam Core
    Plywood
    Strip/West System
Anything else would be just too heavy for a multi."
I would add Polycore to this list

David

Mick@itc
Posts: 69
Joined: Sat Jan 29, 2011 1:29 am
Location: Melbourne Aust

Re: List of Construction types/materials

Post by Mick@itc » Sun Jul 17, 2011 3:30 pm

Thanks guys...
Can I ask some details on the list entries...?

Foam core is some kind of foam sheeting ( can someone tell me what the material is or materials are), covered by epoxy and fiberglass, then high build and then paint. Correct?

Plywood is the same thing with a plywood core...and this is where gamboon?? comes in?. Did I spell that right...I don't think so!

Strip west system...you will have to explain that one a bit more, is this cedar/tiri strips with something covering it?

And polycore...have no idea what that is...can you give us a run down on the construction layers?

Thanks again
Mick
Mick
If all you have is a hammer...everything is a nail!

Finally
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Location: Cairns

Re: List of Construction types/materials

Post by Finally » Mon Jul 18, 2011 12:12 pm

I am building in Polycore (using both bare and preglassed Polycore) so I will answer that query.

Polycore is a polypropelene honeycomb (made from the same type of plastic as a Tic Tac lid) which can be purchased on its own or preglassed (similar to Duflex) . Different thicknesses of core are used for different applications. For instance the Bulkhead cores are thicker (and therefore heavier) than the core used for the furniture. Bare ploycore is used where compound curves are required (for example the saloon roof) in which case the bare polycore is set up on a frame of some sort to hold the shape required, then glassed both sides.

Here are a couple of photos of some panels with the last photo showing the difference between bare polycore and preglassed polycore http://www.australiancompositepanels.co ... panels.htm

Finishing is the same as Duflex.

Mick@itc
Posts: 69
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Location: Melbourne Aust

Re: List of Construction types/materials

Post by Mick@itc » Mon Jul 18, 2011 8:52 pm

Finally wrote:I am building in Polycore (using both bare and preglassed Polycore) so I will answer that query.

Polycore is a polypropelene honeycomb (made from the same type of plastic as a Tic Tac lid) which can be purchased on its own or preglassed (similar to Duflex) . Different thicknesses of core are used for different applications. For instance the Bulkhead cores are thicker (and therefore heavier) than the core used for the furniture. Bare ploycore is used where compound curves are required (for example the saloon roof) in which case the bare polycore is set up on a frame of some sort to hold the shape required, then glassed both sides.

Here are a couple of photos of some panels with the last photo showing the difference between bare polycore and preglassed polycore http://www.australiancompositepanels.co ... panels.htm

Finishing is the same as Duflex.
Just found a polycore boat called Lyra on a build thread...interesting!

Have found a composite core comparison on the web, but I think it is a bit biased. Lauds foam cores over everything else, but written by an engineer from the foam manufacturing company...??? Sus. Looking forward to getting some more polycore info.

Mick
Mick
If all you have is a hammer...everything is a nail!

44c
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Re: List of Construction types/materials

Post by 44c » Tue Jul 19, 2011 7:04 am

You can also get Duflex with foam core instead of balsa.

Mick@itc
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Re: List of Construction types/materials

Post by Mick@itc » Thu Jul 21, 2011 11:17 am

OK, I'm going to summerise what I have learned re cata (which is where my interest lies)...

The main structure is a laminate of some description. Given its a laminate then we have a number of core materials involved...
  • Plywood,
    wood strip,
    synthitic strip,
    polycore,
    Foam (eg CoreCell),
    Balsa,
From the external shell viewpoint fibreglass is stuck to the outside using one of a number of products that can be used on the various cores, eg epoxys, vinylesters, etc.

These in turn can mostly be either
  • Machine pressed;
    Hand laid;
    Vacumn impregnated
either directly on to a hull shape in strips or sheeted into panels by machine and cut to fit the hull shape. If using sheets then joints are created and fixed using the same glassing technique.

I have put this into a table but can't work out how to add it to the post.

So essencially the choice of material comes down to the core type and the laying technique type, hand layed or panels cut.

Thanks for helping with this. I ahve researched soem papers on core comparisons that I will paste in a new thread.

Regards
Mick
Mick
If all you have is a hammer...everything is a nail!

puremajek
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Re: List of Construction types/materials

Post by puremajek » Thu Jul 21, 2011 10:14 pm

Use photoshop - save as jpeg, then upload via tinypic.com. Send it to me via email (saved in 'excel') if you get stuck and I'll try my 'pure majek' :o (puremajek (at) puremajek.com).
JC
James
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Corley
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Re: List of Construction types/materials

Post by Corley » Wed Sep 21, 2011 5:29 pm

I'm using cold molded technique (triple diagonal) on my c class kraken 25 trimaran rebuild it's probably a little bit heavier than building with strip planking but quite dimensionally stable if not glassing the interior/exterior (I'm just going to put 3 coats of neat resin inside and out, lightweight is most important). This is an off the beach boat racing boat by the way so wont live on the water. I'm using paulownia veneers thicknessed down to 2.2 mm supplied by paulownia paradise in Mordialloc, Victoria.
Multihull news and my projects http://trimaranproject.blogspot.com.au/
Multihull Yacht Club of Victoria http://mycv-news.blogspot.com.au/

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