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Type 3 vs. Type 4 solder paste

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AB

#44985

Type 3 vs. Type 4 solder paste | 9 November, 2006

What are the pros and cons between type 3 and type 4 no clean solder paste (SnPb)?

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#44988

Type 3 vs. Type 4 solder paste | 9 November, 2006

Tin/lead alloys tend to oxidize very easily, affecting solderability. Use the largest particle sized paste possible, because as the particles decrease in size their total surface area per unit mass increases, effecting: * Demands on the flux increases, narrowing the process window. * Potential for solder balling increases.

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RDR

#44990

Type 3 vs. Type 4 solder paste | 10 November, 2006

Dave hit the cons pretty well for type 4

type 4 is used when you have extremely small apertures and type 3 will not fit into them or release adequately basically. I have not yet had application that requires it but got very close once, .007 circle aperture on 5 mil stencil. Got lucky, product needed redesign and this part went away. we did print it though with type 3 with sucess but it was scary.

Russ

Russ

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#44997

Type 3 vs. Type 4 solder paste | 11 November, 2006

Many use the following guideline when judging the proper paste for a stencil aperature:

You want approximately 5 particles minimum across the smallest aperture.

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