How to build a reef dome!
Our main dome we call MAKAR after the local shipping warfe! We also have FISHPORT, MUSHROOM and CAMBRIDGE which we dropped as it was too labor intensive and time consuming to build!
In order to keep prices as cheap as possible we have used only materials that are easily available locally! We found the rubber tubs at the fish port, they are very strong and cost about p1,600 a pair but that was good value as the 3 sets we purchased are still alive and in use and as a bi product we make heavy duty plower pots from the moulds!
In order to make the holes in the domes we first used cut banana storks which worked well but after a while my wife growled at us as we were running out of banana plants so we went to a Torno, a lathe guy who made us some tapered hardwood plugs which could be re used many times!
The oil we used for lubricating the forms was not correct mould oil but used vegetable oil that we got from the fast food outlets, being vegetable oil it is not a polutant so it can be used as mould oil is hard to find here!
The steel rings we use for the reinforcement of the lip of the dome is just 7mm deformed bar!
For 3 of these Makar domes we use 2 bags of cement in the mix!
Step 1,
Clean the inside of the base tub and oil, Place in the oiled plugs as required, we added extra depressions made from the cut tops of vinegar or sauce bottles for transplants!
Step 2,
Make up your desired concrete mix and fill the base to the top of the plugs, do not compact the concrete too much as you need air voids in order to cet a bit of a honeycomb finish making life easy for the marine organisms to take hold!
Step 3,
Clean, oil and set in the center of the lower mould your inner form, be sure to weight this down well or it will float when the main side concrete is poured in! The harder and stronger the concrete makes it harder for the marine organisms to colonize the domes so do not allow structural engineers to get involved!
Step 4,
Pill the bottom few inches with concrete and set in your side plugs and keep on filling your sides until about 2 inches from your desired fill hight and set in your steel support ring! This ring is just for support while you get the dome into position, after that is serves no purpose so do not go craze on good steel! once in position cover the steel with concrete up to about 1 inch from the top of the tub, this eill allow the completed form to be removed more easily when set!
We usually cast one set of domes in the morning then remove the inner form in the early afternoon, the main dome is left to cure for 24 hours before the tub is simply flipped over, you jump un the base of the form and the dome should slide free!
The Plugs can then carefully be knocked out and the completed dome left to cure fore a few day before being deployed in the water!
We also make Anchor blocks from these dome moulds!
The domes can be deployed by simply rolling them into position from shore or lowered into the water form a boat on a rope! ow you actually position them is up to your immagination!
I think that explains in easy steps how to build the makar dome, later I will explain about the Mushroom dome!
If you have any questions, please get back to me!
