Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Stencil Design for Resistor Net Array 0402

Jos�

#23930

Stencil Design for Resistor Net Array 0402 | 26 March, 2003

For the Resistor Network Array SMT 0402- 8 pads I'm using a Stencil 5 mils Th. with the next appertures : Corners-biggers pads: 24 x 12 mils Center pads : 9 x 24 mils This Appertures are working excelent for the RN's that his appertures are parallel to the Squegge direction, the problems are with the RN's that are perpendicular to the Squegge direction, in this case Insufficient Solder is the problem. Wich are the appertures to eliminate this problems? Do I have to Use a differents appertures for the RN's depending on the Squegge Direction?

reply »


RDR

#23931

Stencil Design for Resistor Net Array 0402 | 26 March, 2003

Tell us more about your printer. squegge blade type ,speed, snap-off distance etc... You shouldn't have to change apertures for any component based upon its rotation. the parts that are coming out good could they withstand a higher volume print? You may want to increase pad or aperture size across the board. what are the pad sizes on the board? what is the pitch of this Rnet?

Russ

reply »

kenlchin

#23941

Stencil Design for Resistor Net Array 0402 | 27 March, 2003

In printing,the thickness of solder paste perpendicular to the Squegge direction is always lower 1 mil than that parallel to the Squegge direction,so Insufficient Solder may occur.I think you may slow printing speed or widen appertures to resolve it.

reply »

PCB Soldering Tools

SMT in-printer dispensing