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LewsTherin · 05-02-2006, 05:35 PM

Composites

The materials used in this section will be carbon-fibre cloth and epoxy. I recommend West Systems epoxy. You can get it at your local marine supply shop, or at http://www.jamestowndistributors.com

Some things you should know before starting to work with these materials:

-They are expensive
-Its easy to screw up
-Woodworking is required
-Its time-consuming

Step 1, The Moulds

Working with composites/reinforced plastics (RP) requires moulds. The reason for this is that the reinforcing material (carbon fibre) starts out as a cloth (You could make T-shirts out of it) and that the plastic (epoxy) starts out as a liquid. Moulds allow/force your materials to stay the shape you want until the plastic hardens.

There are two types of moulds, male and female.

Male moulds are moulds which you drape your material over. Think of putting a cast on an arm, its sort of like that. These moulds are easier to make than female moulds, and easier to use.

Female moulds are moulds in which your materials are pressed against the insides. Imagine putting a towel in a basket to take food to a picnic in. These moulds, properly done, provide much better results, imo, but are hard to make and work with.

Another part of the female mould is the plug. In male moulds, gravity holds everything in shape. In female moulds, gravity could tear your project apart. The answer to this is the plug. The plug is inserted into the mould after the RP, to keep it pressed against the sides.

Since its easier, and more likely to be used, Ill go over male moulds. If anyone has questions about female/plug moulds, drop me a line.

Creating a male neck mould is actually quite a bit like making a neck. You need to take a wooden blank, and shape it. Note, however, that the mould should be SMALLER than you want the neck to be. Material will be added on top of the mould, meaning your final product is LARGER than the mould.

For the mould, I would suggest using pine or poplar (something cheap). It doesnt need to be structurally sound, it just needs to be the shape you want it to be. This means that a straight peice would be better, but with enough shaping, a curved peice of wood can give you a straight neck mould.

Once you have your mould completed, its time to make something. The basic steps for this are:

-Wrap the mould in plastic wrap, or wax it (this is so your stuff doesnt stick to the mould)
-Cut out peices of cloth for the neck. Especially going around curves, leaving extra is recommended, so you can tuck it underneath and keep the cloth curving properly.
-Dry fit everything. Make sure you have enough cloth prepared. 2-4 layers at a time is best.
-Mix up some resin, according to the directions. Once you do this, we'll have to move quickly. Resin only stays liquid for so long. Before doing this step, make sure you have an idea what youll be doing next.
-Now, you can do one of two things. You can lay the first layer down, then saturate it with resin, or you can saturate it first, then lay it down. I prefer the second method. It stays better.
-Repeat with following layers. Make sure you have no air bubbles between layers.

(to be continued)

05-02-2006, 05:35 PM	#5
LewsTherin MX Warwick Club HUZZAH! Join Date: Oct 2004 Location: CMass USA Posts: 8,590	Composites The materials used in this section will be carbon-fibre cloth and epoxy. I recommend West Systems epoxy. You can get it at your local marine supply shop, or at http://www.jamestowndistributors.com Some things you should know before starting to work with these materials: -They are expensive -Its easy to screw up -Woodworking is required -Its time-consuming Step 1, The Moulds Working with composites/reinforced plastics (RP) requires moulds. The reason for this is that the reinforcing material (carbon fibre) starts out as a cloth (You could make T-shirts out of it) and that the plastic (epoxy) starts out as a liquid. Moulds allow/force your materials to stay the shape you want until the plastic hardens. There are two types of moulds, male and female. Male moulds are moulds which you drape your material over. Think of putting a cast on an arm, its sort of like that. These moulds are easier to make than female moulds, and easier to use. Female moulds are moulds in which your materials are pressed against the insides. Imagine putting a towel in a basket to take food to a picnic in. These moulds, properly done, provide much better results, imo, but are hard to make and work with. Another part of the female mould is the plug. In male moulds, gravity holds everything in shape. In female moulds, gravity could tear your project apart. The answer to this is the plug. The plug is inserted into the mould after the RP, to keep it pressed against the sides. Since its easier, and more likely to be used, Ill go over male moulds. If anyone has questions about female/plug moulds, drop me a line. Creating a male neck mould is actually quite a bit like making a neck. You need to take a wooden blank, and shape it. Note, however, that the mould should be SMALLER than you want the neck to be. Material will be added on top of the mould, meaning your final product is LARGER than the mould. For the mould, I would suggest using pine or poplar (something cheap). It doesnt need to be structurally sound, it just needs to be the shape you want it to be. This means that a straight peice would be better, but with enough shaping, a curved peice of wood can give you a straight neck mould. Once you have your mould completed, its time to make something. The basic steps for this are: -Wrap the mould in plastic wrap, or wax it (this is so your stuff doesnt stick to the mould) -Cut out peices of cloth for the neck. Especially going around curves, leaving extra is recommended, so you can tuck it underneath and keep the cloth curving properly. -Dry fit everything. Make sure you have enough cloth prepared. 2-4 layers at a time is best. -Mix up some resin, according to the directions. Once you do this, we'll have to move quickly. Resin only stays liquid for so long. Before doing this step, make sure you have an idea what youll be doing next. -Now, you can do one of two things. You can lay the first layer down, then saturate it with resin, or you can saturate it first, then lay it down. I prefer the second method. It stays better. -Repeat with following layers. Make sure you have no air bubbles between layers. (to be continued) Last edited by LewsTherin; 06-26-2006 at 07:48 AM.