Introduction: Concrete End Table
Completed form : 24" x 14" x 12" Shaped out of GFRC. Hand packed and troweled.
Weight: 70 #
Color: Black Oxide
Materials for mold:
- 4x8x3/4" sheet of melamine
- half sheet of bender ply
- 1 5/8 drywall screws
- 1 tube black silicone
- 2" ridged foam
- 75 # of GFRC and activator
Step 1: Melamine Mold and Pour
The sides are fairly straight forward..Cut and assemble.
The center dividers and bottom piece were copied from a shaped template by using a laminate trimmer with a bearing bit.
The shaped inner walls were bent into place using bender ply, screws, clamps and a lot of patience.
Insert the the shaped dividers to keep it all together and add a little hot glue
All corners were sealed with silicone.
The Pour:
Sorry no pics as I was elbow deep in black GFRC.
Once you have properly blended said mixture [ it should be the consistency of clay ] its off to the races.Hand packing the bottom first and then up the sides.. I had made shaped 2" foam to be stacked and placed inside the GFRC sides. These were needed to support the last layer as we topped out . We tried for 1/2" to 3/4" wall thickness everywhere. Troweling the top layer flat. This mixture gets hot so when you have a closed form like this you need to provide a way to vent the internal pressure. I tried pin holes ..not enough and ended with a somewhat distorted top surface.
Step 2: Demolding
- Next day I carefully removed the sides
- Pulled out the shaped dividers and voila!
Step 3: WET POLISHING
Not sure if the time was well spent here. Wrestling around with a wet 70 pound piece was a challenge. Went thru the grits with a wet polisher to mellow out the lumps created by the expanding trapped air.The inner surfaces were worked with diamond hand pads and abraded knuckles ..Kept flipping it around until I had enough.. The vertical sides were hard to keep clean as the slurry would run down and leave a stain on the polished surface. Next time!

Runner Up in the
Concrete and Casting Contest
4 Comments
7 years ago
I love it! great job!
8 years ago
Seems to have turned out pretty good. It can be tough to keep the positive deliverables in mind when castings run errant from intention. Your design and planning seems initially sound, so just chip away next time. :o)
8 years ago
That's pretty cool. I'm surprised that it only weighs 70lbs. Matching coffee table next?
8 years ago
Great table design. Very original.