How to Make a Star with String

How to Make a Star with String

Making string figures is a pastime that kids and adults throughout the world have enjoyed for thousands of years. It's also really fun! If you've made the Cup and Saucer you're just a couple steps away from making the Star!

Steps

1. Make the Cup and Saucer using a short string loop or a regular size loop that has been doubled.
   
2. Hold your hands with fingers pointing up. Look at the center of the figure where the bottom of the cup sits on the saucer. This part is made up of three strings. Two are crossed and go to the near side of the forefingers; the other is on top and loops around the far forefinger/far thumb strings.
   
3. Use your little fingers to pick up this top straight string as shown.
   
4. Release the strings on your thumbs.
   
5. Move your thumbs over the forefinger nooses and pick up the near little finger strings. Allow the loose string to go over the strings you are pulling back with your thumbs.
   
6. Release the string noose on your right little finger.
   
7. Finished.
   
   
   

Tips

• To determine the correct length of string for your hand size, hold the end of the string between your thumb and against the edge of your palm, then wrap the string loosely around your palm (but not thumb) 8 times. Cut the string and tie or melt the ends together.
• You can simply tie the string together with a square knot (don't tie a granny knot), then trim off the ends, but eventually you'll want a knotless string loop.
• Craft stores also have braided nylon string that can be used. Some figures come out best if you use a thin slippery string, and heavy-test braided nylon fishing line works well. A thicker nylon string is also readily available and works well.
• There are many more string figure games. It is a great pastime and you can find more figures through wikiHow, books, or websites.
• This is much easier to make with a shorter string loop. You can use whatever string you can find laying about, including yarn, but nylon string works best.

How to Make Baby Food

How to Make Baby Food

If you want to be in complete control of what your baby eats, making baby food instead of buying it is an excellent choice. Food that comes in a jar or pouch is often highly processed and combined with sodium and sugars, plus it's more expensive. When you make baby food at home, you can choose your baby's favorite fruits, vegetables and meats, steam and puree them using a food processor, and freeze them in convenient portions. If nothing but the most nutritious, delicious food will do for your baby, nothing beats making it yourself.

Steps

Picking Out Ingredients

1. Use fresh produce at peak ripeness. Produce is at its most nutritious and flavorful when it's perfectly ripe. Since you won't be adding sugar and salt to the food, it's important to choose ripe produce - otherwise, it will taste bland. Look for produce that is brightly colored and ripe without being too soft or bruised.^[1] Follow individual guides for each type of fruit and vegetable to determine when specific items are ripe.
   
   
   
   
   
   • Farmer's markets are great places to find fresh produce at its peak, since they tend to stock only fruits and vegetables that are in season.
   • You can use frozen or canned fruits and vegetables, but it's better to use fresh whenever possible. Frozen and canned fruits and vegetables often have additives to help preserve them. Read the label carefully if you decide to buy frozen or canned vegetables.
2. Choose organic produce when possible. Many fresh fruits and vegetables are treated with pesticides and other chemicals before they are harvested. If possible, shop in the organic section of your supermarket so you can be sure the food you make for your baby is chemical-free.
   
   
   
   
   
   • Some fruits and vegetables are more apt to become contaminated by fruits and vegetables than others. For example, apples are treated with more pesticides than any other produce, so you may want to go out of your way to buy organic apples.^[2] Avocados, on the other hand, aren't treated with as many pesticides.
     
     
     
     
     
3. Know which foods your baby can eat. Some babies are ready to start eating solid food as early as 4 months old, while others aren't quite ready that early. Talk to your pediatrician about starting your child on solid foods. When your baby is ready, the transition should be slow; introduce just a few foods at once.
   • Babies transitioning from a diet of breast milk or formula-only can have pureed fruits and vegetables, like banana, squash, sweet potatoes, and applies.^[3]
     
     
     
     
     
   • Babies who have eaten some solid foods and are between the ages of 4 and 8 months can have pureed or strained vegetables and fruits, meats, legumes, and cereals.^[4]
     
     
     
     
     
   • Talk to your doctor about when to introduce mashed foods and finger foods to your baby's diet. It's important to do so only after the baby has developed certain skills.^[5]
     
     
     
     
     
4. Know which foods babies shouldn't consume. Babies under one year of age should not be fed certain foods, since they can cause allergies and other illnesses. Never feed a baby these types of foods until after he or she has reached one year of age:^[6]
   
   
   
   
   
   • Dairy products made from unpasteurized milk
   • Honey
   • Outdated canned food
   • Home-canned food
   • Food from dented cans

Preparing Baby Food

1. Wash and peel the produce. Use a scrubber to scrub the skin of the vegetables and fruits, especially if it isn't organic. Make sure to wash off any dirt or grit. If the vegetable or fruit has a peel, use a peeler to remove it, since tough skins are difficult for a baby to eat.
   
   
   
   
   
2. Chop the produce into 1-inch pieces. Since you're going to steam the produce, you'll need to chop it into equal-sized pieces so that it will steam efficiently and evenly. Chop squash, sweet potatoes, applies, or whatever type of produce you have using a sharp knife.
   
   
   
   
   
   • Bananas and other very soft foods don't need to be steamed before you puree them.
   • Be sure to use clean cutting boards and knives. If you're processing more than one kind of food, wash the cutting board and knife with hot, soapy water in between foods.
3. Steam the food. Place the food pieces in a steamer basket. Add a few inches of water to a large stockpot. Cover the pot and place it on the stove over medium high heat. Remove the pot from heat once the food pieces are soft, after 5 - 10 minutes.
   
   
   
   
   
   • Use a clean fork to test the food pieces to see if they are soft.
   • Steam the food to a softer texture than you'd normally do for yourself, since it should be completely smooth once you puree it.
   • Only use water to steam the produce; don't add butter, salt, sugar, or any other ingredients unless you're sure your baby can digest them.
4. Puree the food in a food processor. Place the soft food pieces in a food processor and process them until completely smooth. If you don't have a food processor, you can use blender, food grinder, or a potato masher.
   
   
   
   
   
   
   • Be sure no chunks of food remain if your baby is under 6 months old. Older babies may be ready for mashed, rather than pureed, food. Clear this with your doctor before deciding how much to process the food.
     
     
     
     
     
     
5. Cook meat to the correct internal temperature before pureeing. If you're preparing meat, chicken or fish for an older baby, be sure to cook it to the correct internal temperature to kill bacteria. Use a meat thermometer to be sure. Meat should reach an internal temperature of 160 degrees F, chicken should reach 165 degrees F, and fish should reach 145 degrees F.
   
   
   
   
   
   • Cooked meat may be pureed just like any other food. You can mix it with tomatoes or another savory produce item.
6. Strain the baby food through a fine mesh strainer to eliminate any solids. This final step will ensure the texture of the food is appropriate for your baby's system.
   
   
   
   
   

Storing and Reheating Baby Food

1. Store the baby food in clean glass jars. Portion it into jars with tight-sealing lids to ensure the food stays fresh and doesn't get contaminated. Store it in the refrigerator for up to 2 days before using (1 day for meat and fish).^[7]
   
   
   
   
   
   • If you're storing food in the freezer, be sure to use freezer-safe containers. Baby food may be kept in the freezer for up to 1 month.
   • Always label the food with the type of food and the date you processed it.
2. Reheat frozen baby food thoroughly. It should be completely reheated to an internal temperature of 165 degrees F.
   • Don't defrost baby food at room temperature. This may allow bacteria to grow. It's safer to actually heat the food before serving.

Tips

• Fruits puree and blend much smoother and easier If they have been warmed even a little bit before blended. Consider putting the fruit in a microwave or oven for a very small amount of time before blending.
• Baby food freezes nicely. Spoon pureed baby food into ice-cube trays that have been sprayed with a non-stick spray and freeze. Once solid remove and wrap individually in plastic wrap and place into freezer bags. Unwrap and microwave (gently) as needed.

Warnings

• (Caution: if food is too hot or too much is placed in the appliance pressure from the heat will build, blowing the top off the appliance causing burns and a horrible mess, never leave the appliance unattended).

How to Make a Pie Crust Ahead of Time

How to Make a Pie Crust Ahead of Time

Making pies can be a very time consuming project. If you can make part of it ahead of time, you can make it a lot easier on yourself. This recipe will can be made ahead of time and frozen or refrigerated.

Ingredients

• 4 cups (500g) flour
• 1 tablespoon sugar
• 1 egg
• 1 tablespoon vinegar
• 2 teaspoons salt
• 1 3/4 cups (360g) butter
• 1/2 cup (120 ml) water

Steps

1. Mix flour, salt and sugar together.
   
   
   
   
   
2. Blend in the butter.
   
   
   
   
   
3. Mix together egg, water and vinegar.
   
   
   
   
   
4. Add to butter mixture.
5. Divide into 4 portions.
   
   
   
   
   
6. Refrigerate 30 minutes before using.
   
   
   
   
   
   • Freeze the dough if you want to preserve it for later. You may freeze balls of dough.
   • Don't refrigerate if freezing.
7. To thaw, take out of freezer for a couple of hours then roll out for pie.
   
   
   
   
   
8. Finished.
   
   
   

Things You'll Need

• Bowl
• Plastic wrap

How to Make a Personal PowerPlant

The personal powerPlant is a portable device that harnesses electricity through a solar cell and hand crank generator, into a NiMH battery. The device also includes a visual multimeter that monitors the amount of energy stored. The personal powerPlant can be used to power applications up to 8V at 70 mA.

Designed by: Mouna Andraos, Jennifer Broutin, Carmen Trudell with Mike Dory @ Eyebeam for the Alternative Energy Workshop 06.23.07

Step 1: Materials

Electronics
For the powerPlant circuit
1 - Stepper motor (Japan Servo KP4M4-029 12VDC)
1 - Solar panel (8V)
1 - NiMH battery (7.2V, 70 mA)
8 - 1N4001 Diodes
3 - Terminals
1 - 5 pin male header
18 or 20 gauge solid wire (red, black, blue, green)

For the visual multimeter
1 - Red LED, 1.5V
1 - Yellow LED, 1.5 V
1 - Green LED, 1.5 V
1 - 100 Ohm resistor
1 - 150 Ohm resistor
1 - 1N4730 (3.9V) zener diode
1 - 1N4733 (5.1V) zener diode
1 - 1N4737 (7.5V) zener diode
1 - momentary switch

Hardware 
1 - 2.5"x1.75" PCB prototyping board
1 - Printed Board Diagram (download pdf below)
Schematic Circuit Diagram for reference (download pdf below)

Parts
Case Template (download dwg/pdf below)
1 - 3.5"x3.5"x4.5" Acrylic Box
1 - 3/16"x1" Binding Post with screw
3 - 3/16"x1/4" Binding Post with screw
3 - #10 SAE Washer
2 - #4 machine screw bolts
Gear Template (optional, download dwg/pdf below)
1 - 4"x5"x1/8" sheet plexiglass for Gears (optional)

Equipment
Soldering iron
Solder
Multimeter
Wire Stripper
Screwdrivers (Phillips and Flathead)
Exacto Knife and Blade

Places to find supplies:
Home Depot
Radio Shack
Container Store
Electronics Goldmine
Solarbotics
Jameco Electronics

Step 2: Printed Board Diagram

Print out a copy of the Printed Board Diagram and cut out. Place diagram on side of PCB Prototyping Board without copper solder rings. The diagram will show you how to place your components on one side and on the other you will solder your components to the prototyping board.

Step 3: Coil 1 Rectifier

Insert 4 of the 1N4001 Diodes into place as shown below. The diodes must be inserted in the direction indicated on the Printed Board Diagram; otherwise they will not function properly. By placing the 4 diodes as indicated you are rectifying (turning power from 2 phases of 4 phase stepper motor from AC to DC current) Coil 1.

Step 4: Coil 2 Rectifier

Insert another 4 1N4001 Diodes into place as shown below. By placing these 4 diodes as indicated you are rectifying (turning power from 2 phases of a 4 phase stepper motor from AC to DC current) Coil 2.

Step 5: Coil 1&2 Wires and Header

Cut two peices of blue wire and two peices of green wire with the wire strippers. Strip each end of each piece of wire. Insert wire into place as shown.

Insert 5 pin male header as indicated, with short side of pins facing down into the prototyping board. This is where the motor will be attached to the circuit.

Step 6: Soldering

Turn the board over and begin to solder the connections as shown on the Printed Board Diagram with your soldering iron and solder. It is easier to solder if wires are criss-crossed beforehand. Be sure to join the connections with a good amount of solder. Avoid cold joints (when solder appears matte).

Step 7: Finish Stepper Motor (Generator) Circuit

When you have finished soldering the stepper motor (generator) circuit the back of your prototyping board should appear as shown.

Step 8: Terminals

Insert 2 terminals, one at either end of the prototyping board in direction as shown. If the perforations are too small, use your Exacto Knife to enlarge the hole. Cut two 3" lengths of wire (any color) and use wire strippers to strip wires completely. These wires will run on the opposite side of the prototyping board (with copper solder rings), from positive to positive side of each terminal and negative to negative side of each terminal. The terminal on the left will be used to input wires for the battery. The terminal on the right will be used to input wires for the solar panel.

Step 9: Solder Terminals

Turn over prototyping board. Insert stripped wires into holes as indicated (refer to printed board diagram on other side throughout). Wires can thread in and then out again to get as close as possible to terminal and hold in place as shown. Solder the two north and two south nodes of the rectifiers for coil 1&2 to the open wires running from terminal to terminal. This joins the rectifiers to the terminals to complete the circuit for the stepper motor (generator). Be sure to keep the open wires away from the other connections.

Step 10: Testing

Now you are ready to test the circuit with the stepper motor to make sure that all your connections are soldered properly and all of the components are placed correctly.

Insert the leads of the stepper motor onto the 5 pin male header. The black lead of the stepper motor should be placed on the pin that is not labeled Coil 1 or Coil 2. Use your multimeter (set to DC voltage) to measure the voltage the generator is producing when you turn the shaft. Place the positive (red) probe of the multimeter onto the positive screw of either terminal, and the negative (black) probe onto the negative screw of the same terminal. Turning the shaft by hand should yield in the vicinity of 4-8 volts.

If you are not seeing results, here are some troubleshooting tips:

1)Check all of the solder connections to make sure everything is fully soldered and connected to one another. Conversely, make sure connections that should not be touching are not together.
2)Make sure that all of the diodes are pointed in the proper direction as indicated on the printed board diagram.
3)Check that the leads of the motor are inserted properly - the black wire from the motor should not be placed on either of the Coil 1&2 pins. 

Step 11: Visual Multimeter

The built in Visual Multimeter will allow you to see how much energy is stored from the alternate energy sources without having to use a multimeter.

Insert the zener diodes in the proper direction as shown on the printed board diagram, and according the key as shown on the bottom. The numbers in the key will correspond with the numbers printed on the zener diodes. Insert the resistors in the slots with corresponding colors (in this case the direction does not matter). Cut one peice of black wire and strip both ends, insert next to resistors as shown. Next insert the three LEDs in order as displayed: green, yellow, red (orange).

Step 12: Solder Visual Multimeter

Turn over the prototyping board and solder the visual multimeter in place as indicated. Refer to the printed board diagram on the reverse side. Cross the wires to hold in place and ease soldering. Avoid cold (matte in appearance) connections. Be sure to keep connections seperated that should not be together, as this area is tightly organized.

Step 13: Testing Visual Multimeter

Test the Visual Multimeter to make sure it is functioning.

Place the leads of the stepper motor onto the male header. Turn the shaft of the stepper motor (generator) and see the LEDs light up accordingly.

The green light indicates a voltage of up to ~5.6, the yellow light indicates a voltage of up to ~6.8. Both LEDs guage the voltage dependent upon their brightness. For example, if the battery is holding 6.1 V, then the green light will be bright and the yellow light will be dim.

The red (shown orange here) LED will light only above ~9.2 volts. For this application, the battery used is 7.2 volts and 70 mA. If the red LED lights, the battery is at full capacity. Do not continue to charge the battery with the red LED lit, otherwise it can overcharge and malfunction.


If you are not seeing results, here are some troubleshooting tips:

1)Check all of the solder connections to make sure everything is fully soldered and connected to one another. Conversely, make sure connections that should not be touching are not together.
2)Make sure that all of the zener diodes are pointed in the proper direction as indicated on the printed board diagram.
3)Check the numbers on the zener diodes to make sure they are in the proper order as indicated on the printed board diagram.


*In this image we added a switch and attached the battery early (and then removed them) to see how it worked. This is not necessary, but it is fun.

Step 14: Solder Momentary Switch and Terminal

Cut 2 long lengths of red wire and two long lengths of black wire. Strip both ends of each wire. Wrap one end of a red wire and one end of a black wire onto the leads of the momentary switch. Wrap one end of a red wire and one end of a black wire onto the leads of the terminal. Solder the 4 wires to the leads. The momentary switch will turn on the visual multimeter and the terminal will be used as the output for the personal powerPlant.

Step 15: Solder Solar Panel

Cut 2 long lengths of wire, one red and one black. Strip both ends of each wire with the wire strippers. Solder the one end of the black wire to the negative lead on the solar panel (should be indicated on panel with "-"). Solder one end of the red wire to the positive lead on the solar panel (should be indicated on panel with "+").

Step 16: Case: Openings

Use the Case Template provided (downloadable in step 1) to determine and cut holes necessary for components. We used a laser cutter to score the holes for accuracy (as this type of acrylic does not like to be cut through on the laser cutter), and then drilled the holes accordingly.

Step 17: Gears (optional)

This step is not necessary, but is a nice addition to the personal powerPlant. The gears assist a quicker rotation of the stepper motor shaft, yielding more power.

Use the Gear Template provided (download in step 1) to cut a small and large gear into a 4"x5"x1/8" sheet of plexiglass. We used a laser cutter, as this is much more accurate. Since these gears have small cogs, we do not recommend cutting by hand.

An alternative to this gear set is to purchase ready made gears.

Step 18: Case: Stepper Motor and Small Gear

Insert stepper motor into case as shown with screws of motor facing out of box. Attach screws to case with 2 #4 machine screw bolts. Place a #10 washer on the shaft of the motor coming out of the box, and then place the small gear (optional) on top as indicated.

Step 19: Case: Large Gear (optional)

Insert the post of the 3/16"x1" binding screw between the case and the large gear into the hole on the edge of the large gear as shown. Wind the scew into the post. This will be the handle to turn the gear.

Then insert the post of a 3/16"x1/4" binding screw inside of the box and through the hole as shown. Place one #10 SAE washer onto the post and then place the large gear on top. Finish by winding the screw into the post.

Test the gear with the handle to see how smoothly they run!

Step 20: Case: Solar Panel

Insert Solar Panel inside box as shown with cell side facing outward. Take the posts from two 3/16"x1/4" binder screws and slide one #10 SAE washer on each. Put the posts inside the case and slide them through the holes on either side of the solar panel. Wind the screws into their respective posts.

Step 21: Case: Switch and Terminal

Insert the momentary switch and terminal into the openings as indicated. The leads should be inside of the case.

Step 22: Case: Prototyping Board and Battery

Place your Prototyping Board with finished circuitry inside of the box as indicated. Foam tape can be used to secure the circuit to the inside of the case once the leads from the battery, solar cell, stepper motor and output terminal are attached. Make sure to not tape over any soldered connections.

Place the battery on the bottom of the case, next to the stepper motor as indicated. Secure with foam tape once leads are attached to circuit.

Step 23: Solder Output Terminal

Take the positive (red) and negative (black) leads of the output terminal an insert into the prototyping board in their respective slots as indicated. Solder the leads to battery terminal on the reverse side.

Step 24: Solder Switch

Insert leads from switch into the slots as indicated (center of image). Note that positive and negative placement does not matter for the switch.

Be sure to solder the leads as indicated on the printed board diagram.

Step 25: Attach Solar Panel

Loosen the screws on the terminal for the solar panel. Insert leads from solar panel into the openings of the terminal with positive and negative placement as indicated. Tighten the screws and check that the leads are held in securely.

Step 26: Attach NiMH Battery

Loosen the screws on the terminal for the NiMH battery. Insert leads from NiMH battery into the openings of the terminal with positive and negative placement as indicated. Tighten the screws and check that the leads are held in securely. 

Step 27: Finished!

Test your personal powerPlant to see how it works!

Turn the handcrank for a little while and then push the button on the switch and watch as the visual multimeter displays the amount of power the battery has. Set your powerPlant out in the sun and monitor how much energy it collects. Then use your powerPlant to power devices. We powered our mini arduino with the powerPlant, see what you can power!

Modify your powerPlant to suit your needs. John O'Malley changed out the gears for a rig on his bicycle.

powerPlant_PrintedBoardDiagram 

powerPlant_SchematicCircuitDiagram 

powerPlant_CaseTemplate 

powerPlant_GearTemplate 

Have Fun!