Hi,

I also do 1:1 with copper letting assemblers do whatever they require for paste. Next CM new stencils. Yep, not optimal by a long shot. I assume the CM is knowledgeable about their process (assuming a lot at times) and they can run their own processes better than I. If I can get my own copper pads in the right shape and in the right places then that is about all I can do as my process.

I really like what I have seen come out of the MY600 paste printers and I have written code to drive those. But when you look at what those machines do to aperture shapes and when you consider the nature of the pastes, you just gotta get out of the paste aperture thinking. Just my 2♪. (I can never remember the key code for cents.:-( )

Bob K.

-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of Stadem, Richard D
Sent: Tuesday, May 21, 2019 8:44 AM
To: [log in to unmask]
Subject: Re: [TN] -|EXT|- Re: [TN] IPC-7525A Aperture size in the stencil

When a new stencil is ordered, how are any changes tracked so the new stencil design is modified the same way as before, perhaps 3 years later by another engineer, so it does not come in with 1:1 matching apertures? I'm just asking others for what they do? I have my own methods, but I'm always looking for better alternatives.

-----Original Message-----
From: TechNet <[log in to unmask]> On Behalf Of HEAD James
Sent: Tuesday, May 21, 2019 1:43 AM
To: [log in to unmask]
Subject: Re: [TN] -|EXT|- Re: [TN] IPC-7525A Aperture size in the stencil

As a designer, I output solder paste gerber at 1:1 size with the copper land and include a clear instruction on both the solder paste gerber layers and the accompanying instructions that the PCB assembler and solder paste screen fabricator are to work together to adjust solder paste apertures to suit their assembly processes.

Regards,

James