NFRC Float Instructions


A complete floating island can be made of inexpensive Natural Fiber Reinforced Concrete (NFRC). Here are the instructions.

  1. Take a rag soaked in diesel fuel and wipe a plastic Garbage Pail inside.
  2. A plastic Garbage Pail should float about 8.333 pounds per gallon. So, the bigger the better. The inside is angled at a good draft angle, so you can use it as a form, and get the hardened NFRC out of it.
  3. Take your Garbage Pail plastic form, and cover the inside with two layers of NFRC leaving an inspection hole in the bottom-center. This can be formed by screwing a plastic bowl to the bottom-center, or just lay your NFRC around a space big enough to get your fist through. If you screw a bowl to the Pails bottom, use soft wax (such as used to seal a toilet to a sewer pipe,) to fill the screw heads, and the bowl edge. So as to make removal easier.
  4. Put an inch and flap around the top for attaching the float to your Hex.
  5. Size your Hexes just a little larger than your form, you dont really need the bottles around the edge, you can throw a bottle or two inside if you wish, but lay out your up-side-down Hex form, with blockouts for the rope ties to other Hexes and reinforce as with the other ones. (Read my article on Hex Island Segments of NFRC.)
  6. Wait until the NFRC gets hard, from 3 to 7 days, depending on how you mix it. Take the hardened float out of the Garbage Pail form.
  7. Layout your Hex form upside-down on a sandy beach raked flat, and NFRC the whole thing, as before, leaving the center flat where your NFRC float is to attach to it.
  8. Special Chemicals, available at your hardware store or cement supplier, to paint on the wet NFRC in the area where it will attach to the Hex, and on the Hex where the float will attach. This will make the old NFRC stick to the new NFRC.
  9. Set the float in place.
  10. Wait 7 days
  11. Turn your Hex with its float right-side-up. And float in the water and look for leaks, look for bubbles just like you would with an automobile tire.
  12. If it leaks air, plug the leaks on the inside with that same wax, and install your finished Hex Island Segment.
  13. What if you cant get all of the leaks? Through the inspection hole, insert a plastic trash bag. Then blow it up with air, and tie it off.
The actual design is your own, and you are responsible for it. Neither Prof. Hait, nor the Rocky Mountain Research Center bear any responsibility. In most places there are no building codes to make sure things are built right. So you are responsible to do it right.

    Thanks for your interest.

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