How to Build a Polished Concrete Desk

Step 6 Pour Concrete!

Once everything is all prepared, mix up 1 part cement to 3 parts sand and mix well. Add water until the texture of thick oatmeal is achieved. Carefully plop into form. Add until about halfway full, and spread mix up sides. Vibrate VERY well to gt rid of air bubbles. now mix the same concrete mix ratio but add a good amount of glass fiber, and fill mold up the rest of the way. Screed over the top with a straight 2x4.
After a day of drying, cover with wet towels to slow the curing process and increase strength. It is safe to unmold after at least 2 days, preferably three. Unfortunately i didn't vibrate nearly well enough and got some major holes in mine, but all is not lost.

To unmold, i took off the sides, then use a shovel and some bricks as a lever to lift some sides. this caused it to peel off enough to get my fingers under the lip and peel it off the rest of the way.

Comments

[6L6GC]

You should also mist the mold with a trigger spray bottle right before pouring and vibrate as you fill, especially if you're shoveling it in.

[Atarimark]

Since this is not structural you could get away with adding a little more water and still have more than enough strength left to use for a small desk like this and that will help with consolidation/vibration problems.