Prototype I was unable to find a Talking Boris skull and did not want to hack the pirate, so I decided to build a tree frame large enough to fit around the pirate body and operate it in the collapsed mode. Using assorted 2 x 4's and lag bolts, I constructed a cage, wrapped it in chicken wire, made a knothole, covered the monstrosity with burlap and tried to "sew" the burlap into bark. To make matters worse, I built a mechanism powered by an air cylinder that moved tree limbs like arms trying to grab someone.
The reason for no plans here is that it ended up looking like the robot from "Lost in Space", but the mechanism worked perfectly. Visitors were polite, but it was not up to my usual standards.
Haunted Tree 1.0
Working Model The following year I devoted most of my energies to fixing the tree. The original was too bulky and not realistic at all. I rebuilt the frame using 2x4's into a 12" x 12" rectangle, 4 feet in the front and 6 feet in the back.
I used a 12" concrete footing tube 4 feet long, sawed open lengthwise, as the form of the tree trunk. I left the back open to allow access to the guts and make any adjustments, covering it with a strip of burlap. You can use another section of the tube for the top, but I wanted a hole in the tree for Boris so I just used chicken wire to form the top.
At the top of the tube is the mechanism. It is two 36" length ,1/2 " wide x 1/16" thick flat aluminum stock. The form looks like a combination of a "W" and a "V". When the air cylinder is activated, it pulls (downward motion via a pulley) the middle "peak" of the "W" forward and moved the "arms" forward that pivot on the bottom of the "V" (it will make more sense in the pictures).
I did the mechanism through trial and error to get the right lengths using cardboard strips (sorry but I tend to be a visual person rather than a by the plans guy). This allowed me to adjust the positions of the holes to meet the range of motion I wanted. Once I got them set, I drilled the appropriate holes in the aluminum stock (very easy). Your lengths may be different depending on cylinder stroke, size of frame and desired range of motion.
The arm mechanism pivots on the bottom of the "V" and is restricted by screws. Machine screws connect the arm pieces together and I used nylon washers there to reduce friction. I also added scrap strips of aluminum to reduce friction against the frame. The arm is connected to the air cylinder (which pushes down) using the wire cable. This will stretch with use, so leave enough extra to adjust, just connect it to the business end of the cylinder.
