15
Rework Phase III – Component Installation typically consists of the following steps:
1.
Load PCB onto adjustable board fixture (Fig. 7)
2.
With the head UP, load the component in the nest and slide it under the nozzle (Fig. 13-15, 19)
3.
Press <Start> to initiate the RUN/INSTALL cycle. The vacuum turns on. (Fig. 3, Section 4.0, Section
7.0)
4.
Adjust the head Z height down to pick up the component and then up away from the nest (Fig. 15)
5.
Retract the nest and extend the optics train under the nozzle with the component (Fig. 19)
6.
Using the video image and X/Y/Theta adjustments, align the leads (balls) on the component to the pads
on the PCB (Fig. 8-12, 17, 18, 27, Section 4.0)
7.
Retract the optics train, move the head DOWN to the board. (Fig. 19, 13-15)
8.
Adjust the Z height so the component is just touching the board (Fig. 15)
9.
Press the VAC button or footswitch to release the component and continue the cycle (Fig. 3)
10.
Adjust the Z height so the nozzle is approximately 1/8 inch above the top of the component (Fig. 15)
11.
The cycle continues heating through Preheat (PH), Soak (SK) and Reflow (RF) steps. (Section 7.0)
12.
The cycle progresses to the Cooling (CL) step, while air flows through the heater nozzle to freeze the
solder joints. The cycle is complete. (Section 7.0)
13.
When the board has cooled sufficiently, remove it from the board fixture (Fig. 7)
14.
Proceed to electrical test, visual inspection, or x-ray inspection of the reworked assembly as required
Figure 24: Removing Excess Solder
Figure 25: Leveling Pads using Solder Wick & Flux
