Electronics Forum | Wed Oct 20 15:47:14 EDT 1999 | Shane
I am developing a D.O.E for Surface Mount Adhesives and was wondering if anyone out there had any recommendations on a certain brand. I currently have samples of Loctite 3609, 3615, 3618, Heraeus PD955M and MA-420 by Lord Chemicals. I understand Ci
Electronics Forum | Wed Oct 20 10:49:04 EDT 1999 | Brian
Hi! Stu's method is a half-truth. What it measures is the aggregate of all volatile material with a significant vapour pressure at the baking temperature, not just H2O. Short of very complex methods, it could be complemented by a comparitive measur
Electronics Forum | Tue Oct 19 10:53:14 EDT 1999 | Carol Zhang
Hi, I tried to use high temperature solder (540 - 570F)to connect four spacers on the board. The solder mask around the spacers wrinkled a lot.I can even see a few bulbs around it. I use hot plate and solder rings. After hot plate is heated to appr
Electronics Forum | Tue Oct 19 16:59:58 EDT 1999 | Carol Zhang
Hi, thank you for the idea. I may try solder iron, but it much more slower since I have to solder spacers one by one. a stimpson press is used to press the spacer on the board and the edges of the spacers are rolled. Then we solder the edges to
Electronics Forum | Tue Oct 19 19:25:40 EDT 1999 | Jeff Sanchez
Carol, I think the guys are right about you stand off problem but I want to address the wrinkleing of your masking. Although I think the temps you are subjecting the board to are very high and more than likely creating problems of their own. I th
Electronics Forum | Tue Oct 19 09:12:33 EDT 1999 | John O'Brien
Why use labels? They are expensive, fall off, get mangled, etc. If you directly mark the boards, you'll probably save money, enhance traceability, etc. One major contract manufacturer projects payback at 7 months just eliminating label cost and goin
Electronics Forum | Tue Oct 19 15:16:38 EDT 1999 | Frank Stryker
The CCGA is like a BGA except that the columns are more square looking and there are many more of them. They are made of lead so they are very fragile. They are very expensive. There is a special cleaning process they have to go through once it has b
Electronics Forum | Fri Oct 22 11:25:03 EDT 1999 | Boca
I understand what you're looking for, criteria which determmines a good or bad finger. I have not found anything as cut and dried at that, we just eyeball them. If they are very bad they should stick out like a sore thumb. We check for them each s
Electronics Forum | Sun Oct 17 03:36:55 EDT 1999 | Brian
Obviously, clean enough :-) I don't think I've ever seen a specification, although some companies obviously have in-house ones. It would depend on the process used. For ex., if you used Parylene, where the coating is done in a vacuum chamber, you wou
Electronics Forum | Thu Oct 14 23:01:48 EDT 1999 | Dennis O'Donnell
With loaded boards, warpage can be removed by placing the assembly in a wave solder conveyor pallet as you would if you were going to wave solder the assembly. Place board and fixture in a Blue M forced air oven at 90 C for 30 minutes. Let cool to r
