After getting the picker fingers around the fruit, you pull the string to close the flexible "fingers". Twist the fruit to break the stem, and lower the fruit to the ground.
Although this design works, and the closing fingers are a neat mechanism to play with, you can find a stronger design with no moving parts on my other instructable; http://www.instructables.com/id/Heavy-Duty-Papaya-Picker The heavy-duty design has given me years of service with no problems.
Step 1: Safety while heat forming PVC
Vinyl Chloride, one of the components of PVC, is carcinogenic. When it is locked up in the polymer, however, it is much safer to be around. In my years of experience working with PVC, I have not noticed any adverse effects on my health from being around it.
Always work in areas with good ventilation. If you do get caught in a cloud of smoke, hold your breath and move to clean air.
When heating PVC with a gas stove or propane torch, try not to let it burn. Smoke from burning PVC is bad. With experience one burns it less and less. Don't panic the first time you do burn some. It scorches, but doesn't immediately burst into flame. Move the material away from the flame and try again. Don't breathe the smoke. Smoke avoidance comes naturally for most people.
While heating PVC over a gas flame, keep the plastic an appropriate distance from the flame to avoid scorching the surface before the inside can warm up. It takes time for heat to travel to the center of the material being heated.
Keep the plastic moving, and keep an eye on the state of the plastic. When heated, the PVC material is flexible, like leather. Beyond this stage, you risk scorching it.
A word from James, the plastic engineer -- "Just a word of warning, PVC can handle some high heats but if it catches fire, you wont be able to put it out, it does not need oxygen to burn so don't do this inside".
I do work inside, but my house is made of cement and has good ventilation. MAKE SURE THAT YOU HAVE GOOD VENTILATION. PLAY WITH FIRE -- CAREFULLY.
Step 2: Cut the fingers
I made the saw cuts with a back saw from a miter box, my favorite saw for making straight cuts.
The somewhat conical Styrofoam plug fits between the fingers to spread them apart.
Step 3: Insert the Styrofoam spreader plug
Step 4: Bend and round the finger ends
Heat the plastic until it becomes flexible, bend the finger tips, and wait for it to cool and rigidify again.
I used aviation snips and a file to round off the finger tips.
I did a similar design for picking oranges years ago. It was fun to use, but the fingers, which had flattened areas as joint hinges, tended to get caught in branches and break. This papaya picker does not have flattened hinge lines and is holding up well. Since there is no problem with branches, it should have good longevity.
Step 5: Drill the string holes
Step 6: Make the pole socket
To make the socket, heat the pole end of the picker head over a gas stove until it softens and then jam it over the end of the pole pipe. Inserting the pole into the softened end of the picker head is easier if you trim the inside of the picker head pipe with a knife and the outside of the pole pipe with a file first.
If you ever want to remove the picker head, you can hold the pole down with your foot and tap the head off with a block of wood and a hammer.
You are all set now. Go pick some fruit!