Introduction: Prosthetic Leg Made With Common Household Materials
Finalist in the
Humana Health by Design Contest
In third-world countries, it is hard to get good or even decent medical materials. What if you have been injured in a terrible accident where you lose a leg? It's either you sell your house or you have to be bound to a wheel chair for the rest of your life. This may allow those in those countries to make their life a little bit better.
Questions, Comments, Suggestions or Revisions, please post them so I can improve upon this instructable.
I'd like to give some thanks to stephenniall who gave me the great idea of using a foot shaped thing to hold the shoe in place.
Just wanted to say that if you like this instructable, think about voting for it in the Humana Health by Design Contest.
Thank you !! :)
Step 1: Some Background on the Project Before We Get Started
Sitting at my house I first thought about how I could possibly support all of that weight, or at least how to keep the leg in place so it doesn't randomly fall off. I also thought about how I would even position the leg on top of the device. I then realized that maybe a dome shaped object could be where the knee rests and there is some kind of device on it holding the prosthetic leg in place. I set off looking for a tape measure to measure the diameter of my leg and find a funnel shape. My knee's diameter was 16 inches. I then looked around for a funnel shaped object and found out that an ordinary 2 Liter soda bottle would work nicely. I was then off to find the supporting objects and than it was off to building.
Step 2: Supplies and Precautions
You will need:
* 2 Liter Soda bottle (I used Pepsi)
* Old Shoe
* 1" Schedule 40 PVC¹ (This stuff is insanely strong, i could put all of my body weight on it and it still didn't bend.)
* PVC Primer and cement ( If you don't understand my instructions on how to cement PVC piping together there is a wealth of information on the internet to help you out. Here is a place that may help you with this.)
* 90°, 2 socket, pipe elbow designed for 1" PVC pipe. (While your in the store remeber to check if it fits well on the 1" pipe)
* End Coupler for 1" PVC pipe (Make sure it's NOTThreaded)
* 5 minute epoxy, or any strong epoxy like JB WELD
* Duct tape(optional, you can use it to reinforce the glue points or you could use it also to round off the sharp edges on the cut bottle.)
* 1/2 inch PVC Schedule 40, how much you need will depend on how big your shoe is.
¹(Later in the Instructable I will tell you how to figure out how much you need.)
* Pipe cutter (You can use a hacksaw instead but the cut will be less smoother.)
* Clamp (optional) (I didn't use one but you can to hold parts in place as they dry)
* Scissors or XACTO knife
* Read all warning labels on the glue, don't try to ingest it in any ways or inhale it.
* Use precaution when using the scissors. They can easly wound and leave a scar on you.
* USE COMMON SENSE WHEN USING ANYTHING
* I DONT TAKE ANY RESPONSIBLITY ON ANY HARMS OR INJURIES OR DESTRUCTION CAUSED BY THIS INSTRUCTABLE
Step 3: Making the Dome to Place Your Knee In
1. Take the soda bottle in your hand and either draw a line where the curve meets the straight edge or cut along the label
2. If you're having trouble cutting pinch the cutting edge so you can pierce it easier.
3. Cut fully around the line and set aside until later.
4. Discard all remains
Step 4: (Optional) Taking Out the Sharp Edges From the Bottle
Rip small pieces of duct tape and put them on the rim of the dome as shown in the pictures.
Step 5: Measure for the PVC Parts
Wherever the cut line was on the foot draw or put a line of tape on the other leg and measure there from that line to 1½ inches above the heel(You need to leave room for the elbow joint). (For example, If I had lost my right leg than I would take the line the surgeons cut on and draw it on my left leg and measure on my left leg.) This is one of your PVC measurements. Next, take your shoe of choice and measure from the heel of the shoe to the place where the shoes roof is just a smidgen over 1". You may have to trim down this piece a tiny bit.
Step 6: Cut the PVC
Take your pipe-cutter (or hacksaw) and just cut on the lines you marked from before. That's it for this step
Step 7: Assemble PVC Together
Were almost to the end, only a few more steps. This is pretty easy although it may look overwhelming at first. For those who know how to join PVC together and form a strong bond put the PVC pieces together so they look like it is in the first picture.
BEFORE DOING ANYTHING DRY FIT EVERYTHING
Everybody else, to put PVC together is kinda challenging. It is more difficult than just slapping glue on it and letting it dry. To glue together PVC you must buy two materials: Primer and Cement. They should look like pictures 2 and 3. They usually have an applicator of some sort inside of the can.
First in the process of gluing PVC together you need to take the primer and put a thin coat of it on the inside of the socket and on the outside of the pipe. Then, let it dry for around 10 seconds. Now, take the Cement and apply a thin coat on the inside of the socket and the outside of the pipe piece. Push the two pieces together and give them a 90 degree turn in both directions. This is called solenoid welding. Then let it dry for the recommended amount of time stated on the can.
Step 8: Making a Foot to Hold the Shoe's Place and Shape
To hold the shoe in place we will use the left over soda bottle and some 1/2 inch PVC. What we will do is cut 3 pieces of PVC to act like the toes holding the shoe in place. You can also swap out shoes as they get worn out.
First take the leftovers from the 2 Liter bottle and cut a piece that is as wide and as tall as your shoe when the roof hits the 1 inch PVC. Next cut the three pieces of PVC the length of from the end of the 1 inch PVC to the end of the shoe. Since shoes curve, these three pieces will vary in size and will probably look like in picture 2. Take the pieces and glue them in the way that your shoe curves. For example, if your making a leg for your left side the smallest piece should be on the left and vice versa. Remember to look and compare the pieces to your shoe to make sure they are in the right order before gluing.
Step 9: Glue Dome on Top of the PVC
Take the PVC and put the epoxy in a thin layer around the top where the two parts meet. Then take the dome and put the epoxy around the top of the cap area where it meets the PVC. The finished product will be delicate until it dries so wrap some duct tape around it to keep it intact. When it dries, the bond will be like steel.
(For those who don't know how to use JB-Weld, it is quite easy. All you have to do is take the two tubes and mix and equal amount of each and apply to the object you want to bond.)
Step 10: How to Hold It on to Your Body
To hold the leg in place to your body you could either :a. tape it on your leg, or b. drill two holes in the dome and attach a string and hook it to a belt.
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