STARTING RANGES * Pressure � 1 pound/inch of blade (metal); 1.6-3 pound/inch (plastic) * Speed - 0.5 to 3 inch per sec [for standard pitch]; 0.5 to 1 inch per sec [for fine pitch] Your paste supplier�s recommendation is a good place to start. * Separation speed � Start at 50%. Separation speed that is too fast can leave fine pitch stencil apertures clogged, result in paste tailing, and form high edges around the solder paste �brick�. Separation speed that is too slow is too slow. Solder paste selection and stencil design [ie, aperture wall smoothness, aperture ratios, etc.] drive separation speed.
SETTING UP A PRINTER * Set the down stop to default * Start with pressure of about 1 pound/inch of blade. * Adjust the pressure up/down to leave a very thin film on the stencil. * Speed should match your paste [slower speeds wipe cleaner] and apertures [finer pitch needs slower speed].
YOU�RE PRINTING CORRECTLY WHEN: * Paste at least as big in diameter as your thumb is rolling across the stencil. * Paste is filling the apertures. * Squeegee pressure wipes the top of the stencil of clean. * Paste releases from the stencil. * Paste is on the board in nice bricks.
ADDITIONAL INFORMATION * EMPF published an article on printing in Emphasis, but I couldn�t find it in their listing. Their �search�, ummm, er, leaves room for improvement. Maybe Cal can tell us, or maybe just call EMPF and ask [and report back to us]. * Our old friend Brian wrote an excellent article on printing at http://www.smtinfocus.com/processguide_printing.html
* �The Basics of Fine-Pitch Solder Paste Printing� by Alan Hobby, Manager at DEK Printing http://www.dek.com/comms.nsf/3A52AB46BE9D1DD380256957003BE796/F4E635AE9D305396802569FF0052CCF7?opendocument
* Your printer supplier. They like to help new process types understand their machines to help develop a relationship, preclude a war of words, etc. * Search the fine SMTnet Archives.
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