AlistairM
Well-Known Member
I am interested in learning this art, and was wondering if there were any particular internet sites, book etc that are particulary good on the subject.
Thanks
Thanks
Epoxy GRP / construction
- Thread starter AlistairM
- Start date
TQA
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oldsaltoz
Well-Known Member
You Tube has a number of articles
William_H
Well-Known Member
Your title covers a variety of construction methods. TQA has assumed that you want to build a wooden boat shell then encapsulate it with epoxy. Perhaps the most likely scenario for a home builder.
However epoxy is used in this case for its superior attachment to wood.
To build a boat out of all fibreglass then polyester resin is more often used being much cheaper and more stable in uV sunlight.
Epoxy is sometimes used in top end performance boats in the form of Prepreg. This is where the cloth usually carbon fibre is saturated with the epoxy (and hardener) in the factory. It is shipped and stored refrigerated. When it is laid out in the mold it is hardened by high temperature and pressure in an autoclave.
This method is used for aircraft components. The advantage being that the amount of resin is precise so minimum weight for max strength with great consistency.
In a boat hull weight is not such an issue. Unless you are challenging the Americas Cup. Strength and stiffness are achieved with more fibreglass and resin.
Polyester resin is very good at sticking to itself. It hardens quicker under a variety of temp conditions and is less harmful to human skin.
If you want to learn about molding polyester and fibreglass even as a pre training for epoxy then just get some resin and glass and go for it. Of course you will need some instructions. But it can be fun.
In practice you are far better off buying a premolded hull of a chosen design. This is because there is much cost in building molds and after that it is easy to pop out hulls. A Polyester hull will virtually alst forever but a wooden hull with epoxy will still have a limited life as the wood deteriorates over time. But then if you just want a boat second hand is chaepest /best by far. But then some people just want to buold a boat for there own satisfacttion. good luck olewill
However epoxy is used in this case for its superior attachment to wood.
To build a boat out of all fibreglass then polyester resin is more often used being much cheaper and more stable in uV sunlight.
Epoxy is sometimes used in top end performance boats in the form of Prepreg. This is where the cloth usually carbon fibre is saturated with the epoxy (and hardener) in the factory. It is shipped and stored refrigerated. When it is laid out in the mold it is hardened by high temperature and pressure in an autoclave.
This method is used for aircraft components. The advantage being that the amount of resin is precise so minimum weight for max strength with great consistency.
In a boat hull weight is not such an issue. Unless you are challenging the Americas Cup. Strength and stiffness are achieved with more fibreglass and resin.
Polyester resin is very good at sticking to itself. It hardens quicker under a variety of temp conditions and is less harmful to human skin.
If you want to learn about molding polyester and fibreglass even as a pre training for epoxy then just get some resin and glass and go for it. Of course you will need some instructions. But it can be fun.
In practice you are far better off buying a premolded hull of a chosen design. This is because there is much cost in building molds and after that it is easy to pop out hulls. A Polyester hull will virtually alst forever but a wooden hull with epoxy will still have a limited life as the wood deteriorates over time. But then if you just want a boat second hand is chaepest /best by far. But then some people just want to buold a boat for there own satisfacttion. good luck olewill
AlistairM
Well-Known Member
Thank you very much for all your informed replies. My train of thought was around "project boats" and repairing hull holes or damaged decking etc, so I guess the fibre glass and polyester resin is the way forward.
By the sound of things it is probably best to have a go and see how it works (prehaps make a hole in a plastic pot to practice ??)
Thanks again.
By the sound of things it is probably best to have a go and see how it works (prehaps make a hole in a plastic pot to practice ??)
Thanks again.
Tranona
Well-Known Member
There was a series of articles on GRP repairs in PBO about a year ago, covering the basic techniques.
rhumlady
Well-Known Member
If you are looking at doing up an older hull then go down the epoxy route as it sticks better to the original than polyester which is not a good glue. It may look horendously expensive but because you use it in a 1 to 1 ratio resin to glass not 3.5 to 1 as in polyester it is not so bad. I have found that West System is cheaper than most which surprised me. East Coast fibre glass is good for price.
