RE: It's Alive! Part 017

DAB — Tue, 27 Nov 2012 19:51:10 GMT

Hi Monte,

Have you considered using your 3D printer to make the masks?

It looks like a perfect application for stencils.

Just a thought,

DAB

RE: It's Alive! Part 017

vsluiter — Tue, 27 Nov 2012 13:26:24 GMT

Hi!

I'm also getting confused with all the different solder masks; I also found that changing the design rules (.dru) in Eagle can change your soldermask. In my first gerbers I had overlap between the holes of the pads, thus creating one big hole in the soldermask for each row of pins on the QFN. Because I'm smearing the solder paste roughly in place that was unacceptable. After changing the desing rules the soldermask was just as large as the pads. OK for me.

With regard to the paste stencils: in my previous job (where a lot of PCB's were designed) we always sent files with solder paste size equal to pad size to the assembly company. They would trim the large surfaces in small areas. This was done so the assembly house could adapt the design of solder paste stencils with respect to the stencil thickness or with respect to the properties of the solder paste.

Good luck with cutting more stencils!