...
Procedure
Step 1
...
Set up your steciling stencilling station!You want to surround
Get the board that will be brought up and place on a flat surface.
Surround your board with other PCB’s
...
or straight
...
-edged objects to keep it in place.
Cover all corners of the PCB.
Tape down all the surrounding PCB’s to
...
lock the position of the PCB down.
Make sure it is completely level with the table and securely fit.
Step 2
Place and align your stencil!
Place a piece of tape shorter than the width of the stencil and align the stencil with the PCB.
You will use the stencil with the tape as a lever to slot in, paste, and remove PCBs.
Tape can be found in the “EE Tools” drawer or others.
Make sure that your stencil doesn’t get bent or is already bowed.
You want it flush to the surface of your PCB so paste doesn’t get under it.
Step 3
Paste your stencil and PCB!
You can find the paste and applicator in the fridge at the front of the bay.
While holding/securing the stencil down, use your applicator to evenly cover the stencil.
This may take multiple runs with the applicator to get an even covering of the pads.
You may want to be careful with any QFN ICs (e.g. STM32s).
When you’re done, lift the stencil and remove your PCB with tweezers.
Common Mistakes
Not making the PCB enclosure tight enough (the board shifts while applying paste)
Applying too much solder paste to the stencil, causing it to seep under or cross onto other pads
Peeling off the stencil from the enclosure and bending the flat metal