Assembly Instructions: Kit #6
Difficulty level: 2 (simple, but requires the use of a soldering iron)
Printer-friendly assembly instructions in pdf format.
If you want to purchase one of these inexpensive and simple kits, click here.
If you want to understand how it works, click here.
Read all instructions carefully and check the Safety Rules before you start!
Instructions
- Insert the T-pin into one of the caps.
- Insert the rotor core into the same cap as shown below. Apply some pressure to push the rotor core approximately 1/2" (10-12mm) into the cap.
- Put in the wooden insert.
- Insert the pushpin into the other cap.
- Put everything together as shown below. Push the caps towards each other until they cannot move any more. The T-pin must be secured firmly. This process may require some strength. Be careful not to bend the T-pin or poke yourself.
- Glue the magnets to the flat
surfaces of the rotor core with the letter ‘S’ facing outside. Your kit includes 4 magnets. If you want to try 2 magnets first, glue them to
the opposite sides. Straighten the T-pin if necessary. You can check it by
spinning the rotor between your thumb and index finger. Again, be very
careful.
All kits have magnets with the South pole marked. If you want this side to look better you may cut out the white glossy round labels that are provided and paste them to the marked sides. You may do it before attaching the magnets to the rotor. It is recommended to use regular white glue or a glue stick on the labels for better results. - Insert the rotor into the stands marked with blue and silver stars as shown below. Hold the stands and test to see if rotor spins freely. Make final adjustments to the T-pin if necessary.
- Glue the stand with the silver star to the board. Try to cover the corresponding star completely. Align the marks on the stand with the line on the board as shown below. Note that the star's position and the marks are approximate, sometimes you need to move the stands slightly to achieve the lowest friction. Keep in mind that super glue bonds instantly, so try to be as accurate as possible in these procedures.
- Insert the rotor into the stand marked with the blue star. Glue it to the board the same way as the first stand. Leave a gap of about 1/16" (1/32", or 0.8mm on each side) between the rotor and the stands. Test again to see if the rotor spins freely. At this time, or later, you may take the rubber plug and fix it as shown below. You can glue different things to the outer flat surface of the plug. Try to be accurate, redo this step if necessary.
- If you purchased the experimentation kit #2 or #3, instead of steps 10-12 for this
kit, follow these instructions. After that,
please, come back to this page and continue the assembly instructions from
step 13.
Otherwise, insert the nail into the stand with the green star. If it is loose you may apply glue as shown below. - All wire on the spool should be used to wrap around the area between the tape and the head of
the nail.
- Tape one end of wire leaving about 6" (15cm) open. You may use the tape that is already on the nail.
- Wind all the wire in one rotational direction (either clockwise or counterclockwise) moving back and forth along the nail. Try to be as accurate as possible. Do not let the wire slide off the end of the electromagnet.
- Tape the second end of the wire using the same tape. Both open ends of wire should be about 6" (15cm) long.
- Clean about
3/8" (10mm) of the wire tips with fine sandpaper (included) or a sharp
knife to remove the insulation.
- Glue the electromagnet to the board as shown below. Turn the rotor slowly to see if the magnets hit the electromagnet. If one or more do, move the electromagnet back until there is a 1/16" (1.5mm) gap between the electromagnet and the closest magnet on the rotor.
- Bend the leads of the Hall effect
switch as shown below. If your kit includes 1 large piece of hook-up wire, cut
it into 4 pieces of equal length. Strip about 3/8" (10mm) of insulation
on each end of these wire pieces using a sharp knife. Solder three wire pieces
to the Hall effect switch. If you did not use a soldering iron before it is a
good idea to practice on soldering two pieces of wire to each other. See the Links page for tips on soldering.
IMPORTANT: Do not overheat the Hall effect switch when you solder it. The soldering iron heat may destroy this sensitive device. If you were unable to attach the wire in 3 seconds, let the Hall effect IC to cool off, then try it again. Only solder one lead at a time and allow the device to cool before soldering the next connection. Use the same precautions when soldering the transistor. - Bend the Hall effect switch leads 90 degrees with branded side facing outside:
- Insert the Hall effect switch into
its stand. Make sure that the leads of the Hall effect IC do not touch each
other. You may add a drop of glue to keep the IC and wires in place. Glue only
the leads, do not glue IC case to the stand.
IMPORTANT: It is recommended to glue the Hall effect IC to the stand as a last step after the motor is assembled and the best Hall effect switch position is found. - Glue the Hall effect switch holder to the board. The Hall effect switch should be located in front of the magnets at the distance of about 1/8" (3mm) or closer. Check the rotation of the rotor to make sure that the magnets do not hit the Hall effect switch.
- Attach the battery holder to the
board. The battery holder allows you to experiment with 4 different voltage
settings (1.5, 3, 4.5, and 6V DC). You will need 4 AA size batteries.
To understand how the jumper wire works let's take a look at the connections inside the battery holder: - Locate the base (B), collector (C) and emitter (E) leads on the transistor:
- Follow these steps using the wiring diagram for Kit #6 below. You may trim the wires if necessary.
- If you do not plan to use a heat sink you may glue the transistor with branded side up to the board using a small drop of super glue.
- Solder one end of the remaining piece of hook-up wire to the collector of the transistor.
- Solder the other end of that wire, the negative (black) wire of the battery holder, and the wire that is connected to "ground" lead of the Hall effect switch together. It is easier to solder this connection if you twist the wires together first.
- Solder the wire from the "output" lead of the Hall effect switch to the base of the transistor.
- Solder the "supply" lead from the Hall effect switch to the positive (red) battery holder wire.
- Before soldering the electromagnet wires insert the batteries into the battery holder. Briefly connect one of the electromagnet wires to the positive (red) battery holder wire and the other electromagnet wire to the emitter as shown below. If the electromagnet doesn’t repel the permanent magnets away, switch the wires.
- If the motor works, remove the batteries and solder these wires.
- You may tape the wires to the board using scotch tape.
The following diagram shows how to get 1.5, 3, 4.5, and 6 Volts using 1, 2, 3, or 4 batteries and a jumper wire shown in blue color. Arrows show the current flow for 1.5, 3, and 4.5 Volts settings. Could you trace the current when all 4 batteries are inserted (there is no jumper wire in this case)?
Insert bare ends of the jumper wire between the spring and plastic case to make a good contact and hold them in place. This is how the jumper wire is actually used for 3 Volts experiments (one end is disconnected and may serve as on/off switch):
Start with 3V. If the motor does not work, increase voltage to 4.5V. If it still doesn’t
work, ensure that the rotor can rotate freely and check all the connections –
it is important to clean the insulation thoroughly before soldering. Make sure
the batteries are fresh and connected properly. If the motor still does not work
– click here for troubleshooting.
CAUTION: Do not leave the motor
connected to the batteries if the rotor is stalled. High current through the
transistor will make it very hot. It may burn your fingers if you touch it and
eventually may destroy the transistor.
Our experiments showed that the
speed of this motor could be controlled to some extent by an extra magnet the same way the
speed control unit works for reed switch motors (see Assembly Instructions:
Experimentation Kit #1 and How It
Works: Reed Switch Motor). You may buy a speed control unit or just an
additional magnet at our ordering page.
CONGRATULATIONS! You have finished assembling
this electric motor! Click here for
Experiments and Applications.