SMD Stencil Thickness

Hi All,
What stencil thickness should I order in mm if all the components are 1206?

The place I am looking at has 0.004" stainless steel.

http://ohararp.com/product/stainless-steel-stencil-proto/

and 0.0035" Kapton.

Other thicknesses are used for ink, epoxy, thick film, and/or who knows.

For 1206 it won't matter at all, those are the giants of the SMT world

For 0.35mm pitch components, it crucial and probably want 0.08mm or less.

For general reasonable components like SOIC and TSSOP go for 0.1mm (the thickness
of a sheet of ordinary printer paper).

If stainless is as cheap, definitely go for stainless, it won't stretch when clamped, and your
old stencils make brilliant paste squeegees for the next time.

I like 3 mil (0.003"). Anything thicker tends to put down too much paste that then bridges pins on the smaller chips. Even with 3mil, most of my designs for chips with large pads on the bottom have a stencil hole much smaller than the actual pad.

Of course I’m only squeegeeing by hand, so the thicknes variation is unacceptable for production use.

MorganS:
I like 3 mil (0.003"). Anything thicker tends to put down too much paste that then bridges pins on the smaller chips. Even with 3mil, most of my designs for chips with large pads on the bottom have a stencil hole much smaller than the actual pad.

Of course I'm only squeegeeing by hand, so the thickness variation is unacceptable for production use.

We have used 5 mill stainless for years. Held in a rigid square tube aluminum frame. The apertures are shaped to control the squeegee dispersion of the paste and we also do it all by hand. Large belly pads and other large areas are not left fully open, but are a matrix of smaller apertures. I gave away many reels of old 1206 devices quite a few years ago.

Paul