Electronics Forum | Tue Mar 23 09:55:33 EST 1999 | Dan Hughes
| Al, | | In general, I would agree with Justin and Scott, with the exception that I don't feel a laser cut stencil is required when printing 25 and 20 or even 16 mil pitch. We make a good chem etch stencil that will print fine pitch great if you ev
Electronics Forum | Thu Feb 25 18:29:48 EST 1999 | Karl
| Fab Gurus, (Earl) | What are the disadvantages of using paper phrenwhatsit as a substrate. I want to justify changing a substrate from paper to chem3 or FR4 and I need some info regarding long term failure issues, etc. | | Thanks, | Justin | Ther
Electronics Forum | Mon Oct 03 14:14:06 EDT 2005 | Carmichael
My findings were that it wasn't accurate enough to create the crisp aperatures needed for release. That was almost ten years ago when everyone was looking for an alternative to chem-etch however. Water guided laser also showed promise of doing this b
Electronics Forum | Sat Nov 13 14:09:45 EST 1999 | se
First, let me say what I always say: a good chem-etched stencil will print fine pitch. Chem-etch brings trap to the side walls because its a physical by-product of the process. Because they are less expensive you can add electropolish and still save
Electronics Forum | Thu Sep 23 12:47:48 EDT 1999 | Earl Moon
| | | I've had some trouble pasting a test board for a MicroBGA trial. Most of the paste remains in the stencil apertures. | | | The stencil is 6 mil thick, laser cut and electo-polished. | | | The apertures are 12 mil in diameter with 20 mil pitch.
Electronics Forum | Thu Apr 01 22:21:45 EST 1999 | Dave F
| We make an excellent chem-etch stencil. Our customers have had success printing 16 mil pitch without a problem. This is not an advertisement! | | When we try to sell our product to new customers, we find more and more people willing to pay more fo
Electronics Forum | Wed Jul 15 12:22:57 EDT 1998 | Steve Moore
Electropolishing definitely improves the print characteristics of both Laser-cut and Chem-etch stencils. The caveat here is avoid over polishing which results in rounding of the edges and/or enlargement of the openings. Over polishing is typically th
Electronics Forum | Thu Mar 05 13:17:19 EST 1998 | Justin Medernach
| Hello everyone! | Does any know anything about bare board size variations? | Is there a spec. or tolerance? | I'm running small lots of boards and during the screen printing process | I find that I cannot paste each board perfectly.I've tried other
Electronics Forum | Mon Jan 26 08:58:05 EST 1998 | Mike McMonagle
| I have the following questions with regards to the solder printing stencil design : | 1) Is the Electro-polish process recommended for laser cut stencil ? | 2) Should the aperture walls be slanted at an angle or straight wall, i.e. trapezoidal |
Electronics Forum | Thu May 09 10:00:19 EDT 2002 | brianockert
I'd tend to agree with what the others have said. Check the basics, board supports, setup, wiper paper working correctly. If it's a humidity issue, try taking some paste, place it on a chem wipe, and roll it around a bit, which removes some of the mo
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