It has been a very productive weekend so far. We are getting ready to go for a run so I figured a post just for yesterday's big project was appropriate. We got the concrete fireplace surround placed yesterday. I have spent the last couple weeks after work tweaking a concrete fireplace mixture based off of quikcrete.
The before picture with the reinforcement set aside and cardboard down to protect everything.
Now this is a setup. Due to the small size of the mixer, or the large size of the fireplace, I had to do two separate mixtures which makes the logistics interesting. The concrete is based off of quikcrete but I made it stronger and lower shrinkage using various chemical admixtures. It is handy to know the right people. The concrete is black so I had to buy some pigment. The smallest amount of pigment I could buy was for 1 cubic yard of concrete. Since the fireplace is 3 cubic feet, I have lots left. If you need any black concrete objects let me know and I will make you a deal.
Look at those rippling bi-ceps. Our neighbor Mark knows where I can get a 5 cubic foot (this one can only mix about 1.5 cf) gas powered mixer for cheap. Hopefully for the rest of the summer projects we will have more mixing capacity. I can't wait to be placing concrete outside or into more normal shapes.
The black pigment is carbon-based and sucks up the water reducer. By the second half of each load things were getting a little stiff. Normally a vibrator takes care of this but it made too much of a mess to continue using inside.
The forms stayed put and everything finished nice. I hard troweled the top so it should be smooth. Now we have to wait and see how well I got the concrete consolidated down the sides of the form. There wasn't a whole lot of clearance and I might have to fill some honeycombing. Good thing I have lots of leftover materials. Here it is covered with plastic to lock in the freshness.
No comments:
Post a Comment