• Peg And Slot Mechanism Hardware
• Peg And Slot Mechanism Car Bodies

Adventure Team meeting in progress!

Product design: Mechanical systems The Geneva mechanism combines a cam and follower with a peg and slot as shown. For a constant speed rotation input, it produces intermittent part rotation output. It has many applications, for example in moving toys and automata. There's a peg and slot arrangement the two halves of the upper leg sections. If you bore out the hole in the vinyl knee peg a little bit, you should be able to fit the peg onto the slot on one half of the upper leg. To check the fit, snap the two thigh pieces together and see how the peg moves. Science is used in the peg and slot to build and design the mechanism. Provide a sketch showing how this mechanism could be used to collect a payload. The peg and slot collects a payload in this image when the wheel on the right turning and getting in.

In the previous post, I talked about stumbling onto some muscle body GI Joes in my brother-in-law's storage locker. The action figures had suffered the same fate as so many muscle body Joes: the rubber skeleton inside the figure that held all the parts together had rotted away and the arms, legs, and head fell off the body. Since I had always wanted some muscle body Joes for my collection, I thought I could rebuild the figures with the help of some careful Internet searches. Trouble was, there was very little available online for the do-it-yourself rebuilder, so I decided to come up with my own way of rebuilding my Joes. The following is a step-by-step explanation of what I did to make my talking GI Joe Commander whole again. Only time will tell if my repairs will hold up, so I make no promises that this is the best way to go, but if you want to rebuild a muscle body Joe and have no other ideas on how to go about it, I offer my solutions as food for thought. If you did not read the first part of this post, you may want to go back and read about my thought process for these repairs. Okay, here goes:
1) I'm assuming that, like my Joe, your Joe has completely fallen apart. Therefore, let's start by separating the front body piece from the back body piece. To do that, insert a thin screwdriver into the seam between the two sections. The upper arm socket is a good place to start since there is a hole there. Gently work your way along the seam to the neck, wiggling the screwdriver a bit to widen the gap between the two halves. Go slow and don't use too much force or you'll break the body parts. It may take a few passes around the body seam to fully pry it open. Once you get one side partially open, you may also want to place a screwdriver in that side to hold it open while you work on the other side. Eventually, the pins will work loose from the holes they are seated in. With luck, the pins will not break but, in all likelihood, most if not all the pins may break. Don't panic as we will be gluing the whole thing back together with modeling glue.
3) You'll want to use this same technique to pry apart the upper arm sections and the upper leg sections. Remove any leftover rubber bits and lay the pieces on your work table where they will need to go (e.g., upper right arm sections on the upper right hand side of the body, head stalk and head at the top, etc.). You want the work table to look like an exploded drawing of your Joe. That way, you know where the parts are supposed to go back together.

Muscle body GI Joe with body section opened.

2) Once you have the two body halves apart, you can get a view of the inner workings. You will likely have bits of dried rubber inside. Carefully remove the excess rubber. Also, if you are working with a talking Joe, the talking mechanism will be in the body. The mechanism has some foam rubber attached to protect the mechanism. If it is dry rotted, delicately remove the old foam and replace it with new foam that has a sticky side. I used some insulation foam from another household project. Cut it to the size and shape of the old foam and stick it to the mechanism in the appropriate spots. Lift out the mechanism and set it aside for now.
3) With the top of the body removed, you can also see how the legs were attached. In my case, the remnants of the rubber skeleton were visible in Joe's speedo shorts. A loop of rubber still clung to the large peg in his abdomen. Remove the excess rubber bits.
4) The upper leg sections should have a semi-circular cap inside. This sat just above the rubber half-ball part of the rubber skeleton. Since we will be using shock cord to string the legs to the torso, we'll need to create a plastic ball to replace the rubber half-ball. To do this, place some plastic modeling pellets in warm water. When they have softened, remove the blob of melted pellets and begin to shape them into a ball that will sit underneath the semi-circular cap. Once you have the ball at the right size, take a wooden skewer or some other thin, pointed rod and work it through the center of the ball. This will create the hole that the shock cord will pass through. It should only be just big enough for the cord to slide through. Once you have finished creating the ball, see how it fits under the disc and within the thigh pieces. If it's too big, you won't be able to close the two upper leg sections together when you reassemble it. Repeat the process for the other side.
5) Set the balls and caps aside. Now we will concentrate on the knee pegs. The knee pegs from an original GI Joe will work for the muscle body Joe with some adjustments (replacement pegs can be obtained from Cotswold Collectibles). There's a peg and slot arrangement the two halves of the upper leg sections. If you bore out the hole in the vinyl knee peg a little bit, you should be able to fit the peg onto the slot on one half of the upper leg. To check the fit, snap the two thigh pieces together and see how the peg moves. The hole in the top of the calf piece will be too big to receive the knee peg. To make the fit tight, I put some of the soft plastic pellet material into the calf hole and jammed the knee peg into it. The plastic pellet material will fill up the excess space and form a custom hole for the peg. You may have to cut away some excess material that might ooze out the top. With the pegs fitted to size, open up the thigh pieces and set aside. Repeat the process on the other thigh.
6) You can attach the feet to the calf pieces by using a wrist peg from an original Joe. Cut the original rivet out of the foot with needle nose pliers. If you do not have pliers that are small enough, you can use a small saw but be extremely careful not to cut up the foot. With the old rivet removed, line up the wrist peg with the loop inside the opening in the top of the foot. Insert a new rivet (3/32' X 7/16') in the hole on the foot from the small toe side of the foot so that it captures the loop of the peg. Rest the head of the peg on a hard surface and place a center punch inside the tube end of the rivet. Strike carefully with a hammer. The feet might move around loosely, but they will attach to the hole in the bottom of the calf.
7) Okay, this is where it gets a little dodgy. Start with an ten-inch length of shock cord. Wrap it around the long pin in the lower abdomen of the figure, then tie a tight knot in the center, leaving equal lengths of cord on either side of the knot. Run the lengths of cord through the leg holes of the speedo shorts. Place the outer half of the right thigh into the leg hole of the shorts and let it lay flat on the table with the length of cord laying inside the piece.

View of abdomen with shock cord tied around the large peg. The cord runs through both sides of hip sockets into the semi-circular plastic caps and my custom balls that I made. The taut cord is secured with metal end crimps used in jewelry making. Note how the left thigh section fits over the cap and ball.

Thread the semi-circular plastic cap onto the cord, followed by your custom-made plastic ball. Push the two pieces up to the top of the thigh and pull the shock cord taut. While holding everything tightly in place, slide a crimp end onto the cord and up to the bottom of the ball. Then crimp the crimp end with a crimping tool (you might need an extra set of hands to pull this off). When you release the cord, everything should be held tightly in the upper part of the thigh piece. Cut off any excess cord. Be sure that the knee peg is still on the slot in the other thigh segment and glue the inner thigh piece to the outer thigh piece with modeling glue. The cord and ball arrangement, along with the knee peg, should now be securely contained between the two upper leg segments. Repeat the same process with the left thigh.

Another view of the leg repair.

8) When you have finished step 7, the thighs should be attached to the body tautly, but with some twisting movement for poseability. The knee peg which we attached earlier should be held in place by the two halves of the thigh and ready to receive the calf and foot. With legs assembled, we can move on to the top of the figure.

The upper body repair kit from Cotswold Collectibles. The 'T' shaped joints fit into the shoulders, the joints with the balls on one end attach the upper arm to the forearm, and the length of elastic cord is used to attach the head plug to the body.

9) With the figure laying flat on your work table, Take one of the 'T' shaped shoulder joints from your repair kit and place it in the upper left arm segment so that the top of the 'T' is nestled in the appropriate slot. The disc side of the joint will be fitted into the body later.
10) Remove the rivets from the elbow area of the forearms using the same technique as we used on the feet. Take the elbow joint from the repair kit and place the disc side into the slot of the forearm. Slide a new rivet through the hole in the slot starting from the thumb side. Position the head side of the rivet against the table and tap the tube side with a center punch the same way as was done on the feet.

Peg And Slot Mechanism Hardware

11) Set the ball side of the elbow joint into the bottom part of the upper arm. With the two joints in place, glue the top half of the upper arm to the bottom half with modeling glue. Repeat the same process for the right arm.
12) If you are not rebuilding a talking GI Joe, you can skip this step. For those who are, this is when you return the talking mechanism to the chest cavity. In my case, the mechanism was not working, so I replaced the speaker with a new one from Cotswold Collectibles. Simply remove the old speaker and put in the new one, making sure that the indentation in the center of the speaker is facing out toward you. Set the talking mechanism back into the chest on top of the speaker. Thread the pull cord through the grommit in the shoulder and tie the cord to GI Joe's dog tags.

Upper body with talking mechanism in place. The new speaker is underneath the mechanism. Note the shoulder pegs installed in the upper arms, the elbow pegs are in place and connected to the forearm, and the elastic cord is in place to receive the head plug.

Peg And Slot Mechanism Car Bodies

13) We now move on to the head. Take the head plug shock cord from the repair kit and slide the eyelet end over the retaining pin closest to the neck opening in the bottom body section. Set the arms in place with the disc part of the shoulder joint set in the arm socket hole. At this point, you can glue the top half of the body section to the bottom half. Be careful to keep the head plug cord, shoulder joints, and talking mechanism in their proper places as you seal up the body. You don't want to have to crack open the body again once its glued down.
14) Once the body is glued together and the glue has fully dried, you can reattach the head plug and head. You will likely need to heat the head with a hair dryer to remove the head plug. Once you have heated the head, use a pair of needle nosed pliers to grip the head plug and pull down until the plug is removed. Thread the head plug cord through the head plug and pull the cord through the top. While holding the elastic cord taut, slide on the brass piece of tubing provided in the repair kit and crimp it to the top of the plug with a wire crimper. Cut away the excess elastic. Reheat the head with the hair dryer and slide the head over the plug.

Muscle Body Talking GI Joe Commander is fully assembled.

At this point, you can breathe again: your muscle body Joe is fully assembled! While I can't guarantee that this repair will be strong enough to hold up to a full day on the playground with a 10-year-old, it should be sturdy enough so that a middle-aged man can dress him up in some vintage Joe duds and put him on display with the help of a doll stand.
'C'mon, the Adventure Team is needed!'

Thank you so, so much for the marvellous Instructable. I did a Harry Potter themed wood carving which lights up at night. I needed a cover for the back for the batteries that I could remove and replace without having to take the back covers off. I wanted the battery cover to look like the door to the chamber of secrets, so I cut out a snake knot door and added it to a slight variation on your design above and it worked perfectly. Now I can remove the back by twisting and lifting it off, and replace it and lock it back into place with a twist. Marvellous!
I don't have a laser cutter by the way, so I used a scroll saw, and I used ice lolly sticks for the arms. It worked perfectly.
You can find details of this back cover and the entire carving on my website here if you're interested.
http://wordpress.snazziedesignz.com/wood-carving/h...
You can see video clips of the battery cover working on youTube here:
Thanks so much again.