Electronics Forum | Mon Nov 15 12:13:41 EST 1999 | Dave F
Steve: There are guidelines for determining if your aperture has the correct proportions to the foil thickness. Maybe that�s what you�re looking for: 1 Aspect ratio = aperture width/foil thickness Chemically etched SB GT 1.5 Laser cut SB GT 1.2
Electronics Forum | Tue Feb 04 08:32:49 EST 2003 | roertner
In my experience AOI's are good for checking machine setup I.E. first piece inspection. After that the only things they will typically catch are wrong parts, reversed parts, missing parts, and tombstones. I would however suggest getting an AOI with a
Electronics Forum | Wed Mar 07 12:57:15 EST 2007 | John S.
Hover Davis makes a feeder that can be fitted to many pick and place machines. Runs about 7k. I've seen print on demand feeders at tradeshows for about 30k. If you've got enough volume, you could also laser etch. There's more capital involved, bu
Electronics Forum | Thu Mar 25 20:09:35 EDT 2021 | grahamcooper22
What is the QFP pitch ? What aperture dimensions have you chosen ? Is the stencil laser cut then polished ? Your AFTER stencil size looks promising...your BEFORE stencil aperture size looks disastrous...would surely give bridges.. Your pcb pad siz
Electronics Forum | Wed Jun 10 22:19:31 EDT 1998 | Dave F
| | The Tesa company delivers Splice Tape for 8mm, | | 12mm and 16mm. Also special splice tape for 8mm | | paper tape and some splice tools as well. | | Siemens uses for large tape a 'staple' but might | | be patented and then cannot be used outsid
Electronics Forum | Thu Oct 21 14:02:32 EDT 1999 | Ron Costa
We are a contract manufacturer currently building a job with IBM CBGA-255 devices and 20mil QFP's that are close to each other. We use a 6 mil laser cut and electro polished stencil with one to one apertures on the BGA's. The customer is experiencing
Electronics Forum | Fri Sep 08 21:49:24 EDT 2017 | sbar5781
Hello, I have a few PCB boards i am trying to be manufactured that are miniaturized medical devices. Thus they require IPC Class 3 Specs. However as miniature devices they have limited space, including a 0.4mm pitch BGA socket, which currently has
Electronics Forum | Thu Mar 25 23:23:00 EDT 2021 | llawrence
The QFP pitch is 0.5mm. Pad size is 1.475 x 0.3mm, and the new aperture size is 1.32 x 0.22mm. I'm not sure about whether or not it is lasered, but on the newly ordered stencil I selected the polishing option. Looks like the pad width is already 2/3
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 | Mon Sep 22 17:02:58 EDT 2008 | hegemon
You are on the right track Ismir. Essentially however, as the programmer of the machine, I am the one that creates the PCB with the errors to benchmark the settings for the machine. No secret lab though! :-) Easy enough for most any AOI machine to
