I built this table in 2007,
I built just one each, of the dining table, a computer table, and several coffee tables. My intention at the time was to make and sell these, I never succeeded in selling any, but I later decided to make and sell the legs, which can be seen at SpiralConeLegs.com
The table top is 1-inch thick steel reinforced concrete.
I'll cover the legs in another post.
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Step 1: Detail
The table edge is 1/8 x 1-inch stainless steel, the surface is ground and polished concrete.
Step 2: Frame and Reinforcement Construction
I bent the stainless flat bar around a wood and steel mold, welding the ends to form a continuous band.
The steel reinforcement consists of 3/16" cold steel round bar on approximately 2" centers in two directions. Every round bar intersection is welded. Also the ends of these are welded to the stainless flat bar edge of the table.
Nuts are also welded to the bars to provide attachment points for the legs.These were stainless acorn nuts placed to be flush with the bottom surface. Before pouring the concrete, I filled these nuts with melted candle wax so as to not fill them with concrete. I later melted the wax with a soldering iron tip and then blasted it our with compressed air.
The frame thus created becomes an integral form into which the concrete is poured.
Step 3: Polishing
The polishing is done with these diamond impregnated resin discs. These are velcro backed flexible abrasive discs which are really quite wonderful. There are about 8 different grits that you have to work your way through.
You can get a hand held unit, there's a brand called flex, pretty labor intensive and leaves an imperfectly flat surface, which is fine for a one off, but I was wanting to make and sell these tables. I found this machine, called a flatmaster mini, I couldn't afford it, but I called the guy that made them it and talked him into selling me just the guts and I built up the rest of it , mounted a motor, some skate board wheels, switch, water inlet etc. I have since removed the motor to make another tool.
If you do this wet as opposed to dry then there is no dust or inhalation hazard.
The aggregate or rock, can be chosen for it's color, and broken up glass substituted for the rock, is particularly beautiful.
To see more of the legs used here and also some upholstered benches that we are now making, check out our website, SpiralConeLegs.com
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