A couple of years ago, my husband, who is usually a very handy sort, helped me make a dress mold. We used hints from a few sources, including "Threads", but the product was useless.
First problem: The duct tape absorbed heat from my body so the glue got soft, and its weight caused the layers to slide down, creating gaps. We applied some vertical and diagonal pieces of tape to counteract that tendency, but apparently not enough.
As a result of the stretching, there were gaps here and there between strips of duct tape, which we tried to mend with more tape. We used so many layers of tape that clothes which fit me were too small for the dress form.
Then we tried using the form as a mold by blowing expanding foam insulation into the form, but during the setting process, the foam squeezed out on the edges of our mends. Fortunately the bubbles can be cut off.
The biggest problem was getting the pole positioned so that it aligned with the form's long axis in tall three dimensions. No matter what we tried, we couldn't accomplish that even at the start of the drying period, let alone throughout the setting period.
I now have a tilted, lumpy, grotesque dress form that I'll never use.