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BGA-3500 Series Manual 5/01
ly recommended you contact your solder paste manufacturer for recommendations for cleaning the residue
left by their products.
SOLDER PASTE DEPOSITION:
The application of new solder paste can be accomplished with the optional Metcal micro stencils and sup-
plied stencil adapter or with the optional solder paste plates. Please consult your local Metcal representa-
tive for the latest catalog of standard stencils and solder paste plates.
The BGA/CSP-3500 Series Rework System uses individual stencils matched to the component pad pattern
for the precise application of the solder paste.
• Select the micro stencil that matches your component layout.
• Mount the stencil to the supplied stencil adapter using the supplied 3/32” hex driver.
• Remove the vacuum pipette from the placement head and replace it with the stencil assembly.
• Loosen the coplanarity locking screw on the micro stencil adapter and lower the stencil until it
contacts the board. This action should help you position the stencil flat to the board. You may have to
raise and lower the stencil to achieve flatness to the board. Once the stencil is flat, lock into position
with the locking screw.
• Raise the stencil to the top alignment position and pull out the prism to align the stencil over the
board. Using your light controls, adjust the image so you have a clear image of both the board and the
bottom of the stencil. Now using the X, Y and Theta adjustments align the board to the stencil.
• Push in the prism to clear the placement path, rotate the Z-axis knob to place the stencil into contact
with the board.
• Deposit the solder paste using the squeegee supplied with the stencil.
• Raise the stencil to the top alignment position, pull out the prism and inspect the pasted board under
the high magnification supplied by the BGA/CSP-3500 placement unit.
Solder Paste Application using the BGA Stenciling Templates:
• Select the correct solder paste plate for your component and application.
• Position the component onto the component side of the plate (the side with the smaller cut out or
etched component corners).
• Secure the component with the supplied clamp assembly. Please be careful not to over-tighten the
clamp as this can cause the plate to bend which affects print quality.
• Apply solder paste to the solder balls using the supplied squeegee. When printing, make sure the
stencil face remains clean after you print, this ensures correct solder paste volume.
• Carefully remove the component clamp assembly and position the solder paste plate onto the bare
component slide aligning it with the two tooling pins.
• Using the vacuum pipette lift the component from the solder paste plate and continue with the
alignment process.
Flux Application Using the Flux Transfer Plates:
Metcal has pioneered the application of high viscosity paste flux using specialized fixtures to ensure con-
sistent repeatable results. Please consult your Metcal representative for more information.
Please note: For this operation it is required that you select footswitch operation and use the footswitch.
The footswitch selector is located on the back of the BGA/CSP-3500 Base unit, on the left side, next to
the placement head.
