February 25, 2021
Making a connection:
Although a series of snow storms had slowed my progress, also why this post is about ten days later then I hoped, I managed to determine how the top and bottom sections will connect. Understanding that the weight and leverage of the upper section (which will be the cat body and large branch that it rests on) will need an adequate, stable means so that ultimately no breakage or stress over time can cause damage.
I decided to use 3 inch PVC pipe in two sections and build up the lower tree trunk with two more sections of foam. I inserted 3 inch PVC unions in the first section. In order to get the pipe to fit the entire length of the union, the ridge in the center had to be ground out.
The unions were then glued in place with Gorilla glue. The second section was then glued on with a rectangular opening to provide access for adding additional support strength.
To make sure the unions would be secure, and not pull out of the foam, a layer of fiberglass resin and mesh was laid in. Prior to the fiberglass though, a barrier of aluminum foil was glued in because foam and polyester resin do NOT play well together. After the the resin set, a layer of fiberglass resin jelly was used to add more reinforcement.
With the bottom secure, the pipe sections were measured and cut so that the top was even with the two additonal layers of foam. To ensure that the top will have adequate support, I attatched the pipe to a length of 1/2 inch wood board by screwing drain flanges to the board and screwing the pipe to the flanges. Some grinding and sanding was needed to make sure the fit was smooth and secure. I may add fiberglass to the flanges in the future but this should work well enough for the next step which will be blocking out the shapes of the branch and cat.