Product category:
Electronics Manufacturing Materials and Consumables
News Release from: Tecan | Subject: Polished squeegee blades
Edited by the Electronicstalk Editorial
Team on 06 February 2004
Polished blades clean up on lead-free
processing
A new range of "highly polished" squeegee blades outperforms traditional blades when using lead-free pastes.
Printed circuit board producers are again set to benefit significantly from advanced manufacturing techniques as part an ongoing initiative to deliver lead-free manufacturing solutions Tecan has now developed a range of "highly polished" squeegee blades which outperform traditional blades
This article was originally published on Electronicstalk on 24 Oct 2000 at 8.00am (UK)
Related stories
Can-on-board solder migration problems solved
Tecan Components has solved a range of problems associated with automated soldering of RFI screening cans/fences onto PCBs with the introduction of the 'Plimsoll line and lattice bridging stencils'.
Labyrinth RFI screening can brings RFI benefits
A labyrinth RFI screening can is an effective one-part board-level alternative for PCB designs which would otherwise require solid metal enclosures or multiple screening cans.
They offer advantages such as true compatibility with lead-free pastes, optimised aperture fill and paste-conditioning characteristics which extend print life.
Highly polished electroformed squeegee blades have been developed to address the rheology problems associated with less dense lead-free and "no-clean" pastes.
Effectively, these pastes have a tendency to "cling" to a conventional unpolished blade resulting in "paste hang-up" at the end of the print stroke, thereby reducing the paste bead on subsequent print strokes.
Further reading
Mini rework stencils save time and money
Mini stencils from Tecan Stencils ensure accurate repeatable paste deposits are produced when replacing components such as QFPs, PLCCs and BGAs during PCB rework operations.
Prototype micro metal parts in five days
A five-day prototype service has been launched by Tecan, offering design engineers cost-effective small sheet metal parts for a vast array of applications.
The new squeegees deliver a proven solution to all these problems and are particularly beneficial for mixed-component and fine-pitch applications, allowing manufacturers to achieve the most consistent and repeatable performance possible from existing printing machines.
The improved "paste-roll" characteristics aided by reduced surface tension also extends the printing life of the paste.
Furthermore, successful printing can only be achieved with the selection of the most appropriate stencil, solder paste and paste delivery system, says the company.
To achieve the best results, the blades should also possess flexibility to consistently deliver the expected paste volumes.
To this end, Tecan has developed "reactive" metal squeegee blades with a mobile "feathered" edge.
These durable reactive blades have been tested against a range of single thickness metal blades, coated metal blades and traditional polyurethane materials.
In the tests they were proved to provide significant improvements to printed results, when used with either simple single thickness stencils or multi-level stencils featuring both raised and recessed areas.
These mobile-edge squeegees enhance the performance of today's printers by delivering repeatable results, which match the demands of fine pitch printing.
They also provide the solution to the problems of scooping or scavenging that polyurethane squeegees create with larger apertures.
The mobile edge allows the blade to flex locally, to overcome uneven surfaces such as proud via holes, thicker tracks and poor silk-screening - recovering quickly to deliver clean consistent printed results.
This provides significantly better and more accurately defined deposit formations, increased process control and improved product quality.
The blades are an effective solution for printers that use trailing edge squeegees.
They can either be positioned in front of an existing polyurethane squeegee, where the metal edge becomes the printing edge, or, used as a direct replacement for polyurethane squeegees where the holder permits.
• Tecan: contact details and other news
• Email this article to a colleague
• Register for the free Electronicstalk email newsletter
• Electronicstalk Home Page
Search the Pro-Talk network of sites
