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

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Stencil thickness

Views: 2764

#40113

Stencil thickness | 2 March, 2006

I have a board with 0603 parts with .2mm spacing between the parts and in some areas smaller. Can any one help me on what size stencil thickness I need. Any help would be appreciated.

Jay

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Chunks

#40115

Stencil thickness | 2 March, 2006

0603 parts at .2mm spacing is pretty easy. But are there any other parts, like fine pitch QFPs? Is your board HASL or something else? Is there resist/mask between all pads?

If it's just 0603's at .2mm, then you can probably go 7 mils and get good print and no short. Homeplate them so you don't get solder balls/fines.

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Wave Master Larry

#40117

Stencil thickness | 2 March, 2006

WELL, I heer that thikness was always wrong where I work, and for what ever reason the engineering department chose 6 milimeters. Personaly i would of gone 8 myself. I look under the magfying glass and always noticed in-suficient solder on the gulled devices.

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RDR

#40119

Stencil thickness | 2 March, 2006

6 mils maybe? instead of 6mm? We go down to 5 mils and up to 7 with 0603. You could even use a 4mil stencil for these without any problems.

The .2mm (.0078")apart however might get you in trouble unless your equipment is rock solid.

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Chris

#40127

Stencil thickness | 2 March, 2006

Go with no greater than 0.005". Pleanty of paste and minimal shorting issues. 0.004" will even work

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Dirka Jihabi

#40129

Stencil thickness | 2 March, 2006

I disagree with the homeplate approach.

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#40130

Stencil thickness | 2 March, 2006

NC or WS?

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pr

#40134

Stencil thickness | 2 March, 2006

Dis agree?!?!?! We solder plenty of them o6o3s at honda and they l00k 0k! Solder balls will always fall off the b0ard when mounted anyway.

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E. Moon

#40139

Stencil thickness | 2 March, 2006

Are you guys really hiring? I like your thinking!

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#40154

Stencil thickness | 3 March, 2006

MELF shape works perfect for me.

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#40367

Stencil thickness | 13 March, 2006

0.2mm gap between parts is small and easy to solder short. I prefer 5mils or 4mils.

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Reflow Oven

MSD Dry Cabinets