Electronics Forum | Mon Mar 19 09:37:01 EDT 2018 | spoiltforchoice
Another critical part of a process with a large board is support. Most commonly this is a bed of pins e.g something like red-e-set but there are other solutions. Support with a large panel will be critical for printing to get a good gasket between PC
Electronics Forum | Tue Aug 17 10:41:13 EDT 1999 | Steve A
Wayne, Sounds like a gasketing problem. When the horizontal apertures are bleeding but not the vertical apertures. Could be poor underside support, HASL miniscus issues, masking or plugging issues, but what many people do not account for is that t
Electronics Forum | Fri Mar 12 13:30:06 EST 1999 | Bill Schreiber
Dear Scott, You are correct in questioning the chemistry portion of the process. However, I am couriuous as to why you selected DEK as a stencil cleaner. The most important part of any cleaning process is always the chemistry. How you deliver the c
Electronics Forum | Fri Mar 12 13:40:53 EST 1999 | Bill schreiber
In a nutshell, you should be looking for a chemistry first, then look for a machine. Hopefully, they will be from the same source. | Dear Scott, | You are correct in questioning the chemistry portion of the process. However, I am couriuous as to w
Electronics Forum | Wed Dec 18 12:04:53 EST 2002 | slthomas
That issue (gasketing is what I usually see it called) was the driving force behind us getting new printers. Our old semi-auto clamshells just weren't repeatable enough, particularly over changes in squeegee travel direction. If the paste in the
Electronics Forum | Sun Sep 27 13:32:59 EDT 1998 | S. Evers
| | I am looking for anyone out there that has had experience with stenciling with chipbonder adhesives. I need information on material and stencil design. | The firm who can help is K&J marketing their new KEPOCH stencil material is a (plastic) pol
Electronics Forum | Mon Mar 09 16:36:38 EST 1998 | Jim McLenaghan
| We have a double sided pcb that is surface mount on both sides. Now a Through Hole connector has been added. Appart from hand soldering does anyone have info. on reflow soldering the part. The connector is 0.1mm pitch, square legs. | 1) Do you need
Electronics Forum | Wed Jun 14 12:43:52 EDT 2000 | Todd Murphy
Dave, you are right you would expect the soldermask to be higher than all SMT pads on the pcb if it is higher on the fine pitch components, but the other areas of the board do not concern me as much as the fine pitch areas. The pads on all the other
Electronics Forum | Thu Dec 15 11:06:05 EST 2005 | Samir Nagaheenanajar
You might wanna try a small reduction in your stencil aperture. For example, for a 30-mil pad go 26-mil square aperture with 8 to 10-mil radius on your corners. Also, look at your designs. Is there enough resist between your pad and ball? Another
Electronics Forum | Thu May 18 10:20:55 EDT 2006 | slthomas
Russ asks good questions and I think Chunks pretty much nailed it. Aspect ratio (aperture width/stencil thickness) s/b 1.2 minimum (I like 1.5 if I can get it). If your aperture width = lead width (.008"), yours is 1. Tough to get consistent paste r
