But you should do the simple projects, such as Deck Hexes to gain skill in working with NFRC first.
There are several processes that need to be understood from both study and experience. If you are building a form of NFRC, it needs to be reusable. You need to be able to remove the final piece from the form without the piece sticking to the form, and without destroying it.
To do that, the form should not be made such that the piece holds mechanically inside the form. Thus, the form is made such that it has proper “draft angles”, that is, the openings are slightly larger at the top and slightly smaller at the bottom, so that the hardened piece will be more easily removed from the form. This usually requires an angle of at least 2°.
If the form is to be used in high temperatures, such as a Rotomold for plastic, use Refractory Cement, rather than Portland Cement.
Forms can be of a single piece, or multiple pieces you have to dismantle to remove the formed product.
The forms should have flat, slick surfaces, also to prevent the piece you are forming from being stuck mechanically to the form. Thus the NFRC form can be constructed on plastic. This produces a shiny NFRC. Also, when the form is finished, you can coat it with diesel fuel as a form-release. However, NFRC is waterproof, and will tend to not soak up the diesel as wood would.
Therefore, coat the surface with wax. Rub Paraffin Wax into the surface where you don’t want the piece to stick to the form, but only shape the piece.
Plastic drop cloths may also be used for this. And it can make a fine bond-breaker. The problem is the folds in the plastic tend to leave marks in the finished piece. Thus, small projects may use Plexiglas or preformed plastic, such as a plastic trash pail, to avoid such marks. Or use rolled polyethylene as it has the folds further apart.
Some plastic is destroyed by the ultraviolet rays of the Sun, so think about how you intend to use it.
There are 2 types of furniture that you may wish to produce inexpensively with NFRC— Ones with multiple pieces that need to be hooked together, and those of a single piece.
You can build a form from NFRC if you do it right. An example of a single piece is a lawn chair. These you can purchase inexpensively. That’s the easy way. But if you desire to make your own of NFRC chairs, it is possible. You only have to buy one of them.
Notice that the commercial chairs are smartly engineered both for making the chair strong, where it’s needed, and with proper angles so that it can be removed from a form. Thus you can use a commercial one to reproduce the form that was used to make the chair. It’s tricky, but possible.
However, plastic chairs are poured of molten plastic. And NFRC is laid by hand into a mold. Thus the mold you build needs to be open on one side so that you can access it with the fresh NFRC when building the piece you wish. Think about it!
And the final piece needs to be smooth and comfortable to sit in, on the arms and seat where you will be sitting. Thus, the form needs to be made to produce what you desire.
Also, plastic chairs are not fibrous, but your finished product will be. Therefore you don’t want weak spots where the fiber is not continuous, or where old NFRC is being connected to new NFRC. Will you be using Palm leaves that are more continuous, or hair that is more random. You have to adjust your method accordingly.
The 2nd type of furniture is made of multiple pieces that must be assembled. The forms for making them must allow the final pieces to be assembled, and shaped accordingly. There are several ways for assembling the final pieces.
The surface may be colored, or coated with a material as you like. This may be flat, for painting, or textured for spray painting. Coloring may be placed in the NFRC. The availability of colors is limited, but readily available.
Some of your options for surfacing include materials, such as
If your project needs compressive strength, or to spread out the Portland Cement, sand can be added at the traditional level of twice the volume of the Portland. However, it will affect its waterproofness, and must be mixed well. Where the gravel in the traditional mix is replaced with fiber. However, if you get your sand from the bottom of the sea, it first needs to be washed with fresh water.
When Portland Cement cures it needs to be kept moist. One way is cover your NFRC project with a plastic drop cloth to keep it moist for at least a week. Then you can let it dry out.
Afterward, NFRC can also be changed with a jackhammer. However, a little thinking ahead of time can eliminate that step.
It can also be fun and fruitful.
Thanks for your interest.