5. Eutectic Removal Procedure

5.1 Set the temperature control on the Chipmasterä to 440F, and set the timer to zero by:

To set or change Set Point temperature, from the "Operator View Display" press the INDEX key on the controller once to enter the "Operator Menu" then press the INDEX Key, TWICE, to reach the "Temperature Field" ; then press either the "UP" or "DOWN" arrow to reach the desired temperature (RED L.E.D. display). To do this, use the "UP" arrow to increase: hold the button in to increase rapidly. To increase temperature in one-degree increments, press the arrow button in individual steps. The same procedure works for the "DOWN" arrow button. Then press ENTER. Press the INDEX key twice more to return to the "Operator View Display". See Chipmaster Manual for complete explanation of controller and features.

5.2 To reset the timer to zero, in the "Operator View Display" press the ENTER key and the "DOWN" arrow key simultaneously. The display will flash once, indicating that the timer has been reset to zero.

5.3 How The Timer Works:

If the timer is reset to zero, it will START counting UP once the heat cycle begins (Foot Pedal pressed) and will STOP counting once the cycle is stopped by the operator (Foot Pedal released). The timer will display the cycle time, e.g. 1: 45 minutes, or whatever. Each time the foot pedal is depressed to start the cycle thereafter, the timer will count DOWN to zero from whatever cycle time (in this example, 1:45 minutes) was recorded. This is the Timer procedure used for Eutectic Removal.

The procedure for changing cycle time is similar to setting temperature, Press the INDEX key ONCE (from the Operator View Display) to enter the "Operator Menu" and reach the Timer field. Use the "UP" arrow key to increase time in one-second increments; hold the key down to increase rapidly. Once the time is set, press ENTER; then press the INDEX key FOUR times to return to the "Operator View Display" when a specific time has been set, e.g. 2:05 minutes, the Chipmaster's Timer counts down to zero once the foot pedal to start the heat cycle is depressed. The timer will stop at zero, even if the heating continues (foot remains on the pedal). For Eutectic Removal we do not set time to remove a component, as the time will be recorded once the component is automatically removed and the Foot pedal released. However we will change (add) time to replace a component using this process.

 

(Illustration # 5)

 

Install Nozzle 8100-1414 , 66-80332E92, 1.40" x 1.40" ( 35.6mm x 35.6mm) for a QFP208 in the Chipmaster, or appropriate nozzle for any other size component. (Illustration # 5)

Using the no-clean flux paste provided in the SMT Tool Kit apply a thin 0.025" line around the leads of the component, ensure all leads have flux applied and note the orientation of the component for installing a replacement.

Place the board in the Board Holder, as described in the Chipmaster manual and center the component under the Chipmaster Nozzle, the body of the component should be between 1/8" to 1/4" (3mm to 6mm) below the base of the nozzle. (Illustration # 6)

 

(Illustration # 6)

5.7 Depress the foot pedal to start the heating cycle. Note that the GREEN display will begin "counting" the seconds while heating. The RED display will indicate the heated air temperature as it ramps.

5.8 Turn on the vacuum pump, then depress the Vacuum Pickup Assembly to capture the component. The component will not, however, lift off at this time.

5.9 Once the component leads achieve eutectic condition and after approx. 2 minutes 25 seconds of heat application using Profile # 2, the component will automatically rise from the circuit board by the tension applied by the Vacuum Pickup Assembly and be drawn up into the nozzle of the Chipmaster. Release the foot pedal to stop the heating cycle. The GREEN timer display will stop counting, and will record the length of time elapsed.

Depress the board holder piston (cylindrical top of the board holder); remove the entire board and holder from beneath the nozzle assembly by sliding the whole assembly sideways and out from beneath the nozzle. Let the component cool for a while and with a flat surface, such as a small card, place the card under the nozzle, turn off the vacuum pump, using the switch on the front of the Chipmaster. The component should release and drop onto the card.

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