After seeing the prices at some of these landscape places, I decided to try to make my own planting containers. Amy helped me by drawing up the design in CAD to get all the angles so I wouldn’t have to spend a lot of time calculating them. I like math and all, but I wanted the thickness of the concrete to taper for strength which introduces a lot more angles and I was anxious to get started. The project ended up being a little trickier than I expected. I spent a lot of time making the mold real nice and smooth to make it release from the cement after setting, but all my efforts were in vain. I expected the cement to expand when it hardened, but didn’t realize the full impact on my mold. Two of the inner sides could not be removed with out cutting and prying. I have a couple of solutions, but haven’t made the effort to rebuild the mold. It doesn’t look big in the pictures, but it is a foot and a half tall and weighs well over 170 pounds.
The process is to mix and pour the cement into the mold and pack the cement while pouring to avoid air pockets. At the bottom of the pot, use a pipe to make the drain hole. Let it sit and dry for a couple of days. Remove the mold fill in any gaps or rough areas with mortar. Stain with concrete stain of your choice and then seal with a clear coat.
Materials:
- 2.5 80 lb bags of crack resistent Quikcrete
- liquid Quikcrete for patching
- concrete stain
- plywood
- screws
- short pipe 1.5 inches in diameter
04/02/2009 at 6:37 pm Permalink
HI David
Great job on your first mold !! I make our molds out of latex rubber and fibreglass so you can take apart the fibreglass and the rubber absorbs the expansion. So if you need help please let me know.
Keep up the effort
Tim