This post will describe how I built the forms for the wallbreaker. This approach will support cheesecloth in a way that will keep it away from all the strings and moving parts. You can either use this approach or use it as a basis for your own.
Building the forms
I have made some templates you can download and use to create the cardboard pieces used in the following steps, available here. These do not have to be perfect, in fact these forms give you a starting point which will be trimmed at least once while you fit the forms to the wallbreaker and test run the motor to make sure everything clears. I used corrugated cardboard,to follow these steps you will need to cut out the number of forms specified below for each step. I also use a hot glue gun to fasten all the pieces.
Cut out the templates for the chest as shown above. The form is built using hot glue as shown in the following pictures.
The completed form is pushed onto block #19 as shown below. Run the ghost and make sure the dowels turning the head move in the slots without hitting the form. You may also need to trim away part of one of the C3 pieces so the head is able to turn freely back and forth.
Cut out and assemble the shoulder forms as shown in the following pictures. The dimensions for the large piece of cardboard are provided in the templates you can download above. Cut out the piece of cardboard, then cut slots at the shown intervals. Cut out 1 S1 and 2 S2's. S1 is glued along the middle of the large cardboard peice, with the slots sticking out to either side. Glue S1 so the short side is next to the thinner slots.
Once S1 is glued onto the shoulders, position the two S2 pieces as shown below, sliding them down over the dowels.
Next, place the shoulder assembly onto block #12 and attach it with a screw.
Now use hot glue to attach the flaps to the S2 pieces as shown below. I like to use small pieces of masking tape to hold things in place for the couple of minutes it takes for the hot glue to harden.
You will likely need to cut some out of the S2 peices where strings need to go. Make sure to check al strings, and run the ghost to make sure everything clears.
I use cardboard tubes left over from paper towels to build the arm forms. Cut out 4 of the IR2 forms, cutting the slot as shown in 2 of the 4 pieces. Cut out 2 LR2 pieces. Cut a paper towel tube in half lengthwise. You should end up with pieces as shown below.
Glue the IR2 with a notch 2-3" in from one end, and the one without a notch in about the middle. Glue the IR2 piece onto one of the center blocks at the elbow (block #8 or #9, see below). Note that I cut off one of the tabs sticking out, and I positioned LR2 so it would not hit the lower arm dowel as it moved.
The form will sit on the lower arm, with the IR2 piece with the notch down by the hand, and the other end sitting on the LR2 piece at the elbow (see below).
With the form cut, it needs to be trimmed to fit. Position the form so it sits on top of the arm or slightly out by pushing the IR2 with the slot down over the lower arm dowel, then mark and cut a notch by the elbow that will allow the upper arm dowel to move up into the notch. When you see the video later, you will see how the upper arm will move into this notch when the lower arm is pulled up, and how the form will slide out onto LR2 when the lower arm is lowered, but not slide off. For now, make sure the notch is just wide enough so the dowel can slide up into the notch without getting stuck (see below)
Trim enough from the form by the hand so the hand can hang freely, and the hand does not hit the form when the ghost is in motion.
The last form is the upper arm. I also made this using paper towel cardboard tubes. Hold the tube up and cut the tube a little more than the length you think you will need. Cut one for each side.
Cut each tube once lengthwise so it can be opened up. Cut out 2 each of forms UR1 and UR2, and glue these into the open tubes as shown below. Make sure UR1 and UR2 are mounted in different directions for watch arm (see below)
These forms snap onto the upper arm, with UR2 above UR1. Trim the cardboard tube up to the edge of UR2, this gap will provide room for the moving dowels at the top of the arm.
Trim the bottom so it does not hit the lower arm or form while the ghost is in motion. You can see the forms all mounted on the wall breaker below.
The next step is up to you, what do you want you ghost to look like? Just try to keep it light. For the original Wallbreaker I used black broad cloth (cheap at WalMart) and cut pieces that would drape nicely over the forms.
Next, remove the forms from the wallbreaker so you do not get glue or anything else in the lines. I used an Elmer's glue/water mix, dunked the broadcloth in it, squeezed it out and then applied to the forms. Hold the form up so it is oriented like it will be on the ghost, and apply the glue/water/broad cloth over the form, introducing wrinkles, etc if you like. The end result may look something below.
Next I used cheese cloth treated in RIT or whitening detergent, and fabric stiffener to add cheese cloth to the forms. This is a good time to start adding texture or accents using the cheese cloth. The result when shown in black light for my ghost is shown below.
The final step (if you like) is to add some more cheese cloth to fill the voids. Initially I draped some cheese cloth over the forms, but I did not like it (see below) and I decided not to go with this approach.
The next approach I used was to cut some pieces if cheese cloth that could fill some of the voids, and use small dabs of Elmer's glue to secure the cheese cloth in place. The result this looked like that below.
The video showing all of this in action can be viewed below