Electronics Forum | Tue Jan 03 17:38:38 EST 2012 | davef
Here's two ideas fro the fine SMTnet Archives: * On the bare board, during design / layout, the basic shape of the jumper is a 125 thou disc of copper [that of course is eventually covered with whatever solderability preservative we use on the board]
Electronics Forum | Thu Jul 09 11:13:00 EDT 1998 | justin medernach
| IS IT BETTER FOR SOLDER PASTE TO SPREAD OUT AS FAR AS POSSIBLE ON BARE COPPER, OR FOR IT TO KEEP THE SHAPE OF THE PRINT? I'VE BEEN DOING SOME SOLDER PASTE EVALUATIONS, AND I'M TRYING TO EVALUATE THE RESULTS. I'M NOT SURE THAT BECAUSE A PASTE MAY
Electronics Forum | Fri Jan 02 16:52:16 EST 2009 | boardhouse
Hi, From a Manufactures choice - Green is the best due to it is the most commonly used mask color in the industry & cheapest. Kind a like Red paint for Barns. For US shops, most only have one LPI machine and to continually switch from Green to othe
Electronics Forum | Fri Nov 25 15:52:40 EST 2011 | davef
"IPC-2221 - Generic Standard On Printed Board Design" talks to fiducials. Anther take on fiducials says they shall meet the following requirements. * Make fiducials 1 - 1.5 mm diameter circle. * Cover fiducials with tin. * Keep solder mask opening at
Electronics Forum | Mon Sep 14 04:13:53 EDT 1998 | Jeff sanchez
| Thanks for the help, Guys. | As a matter of interest, I'm going to look up the standard and see if there's a European (or preferably UK) equivalent. If I find anything, I'll post another Follow Up (though I doubt it holds much interest for you)! |
Electronics Forum | Mon Sep 23 12:37:56 EDT 2002 | genny
OK, back into the fray after being silent for several days. Yes maybe I was a little cranky. Sorry about that. However, I was starting from scratch, I knew nothing. I was nowhere near the point of evaluating whether XYZ machine was better than 12
Electronics Forum | Tue Mar 09 13:53:21 EST 1999 | Tom B.
We use Siemens equipment at our plant. I agree with what everyone said in the forum. These machines are primarily made for fixed or specfic PCB runs. The feeders are very well built as others have metioned. If you plan on excessive change over's,
Electronics Forum | Thu Dec 26 16:51:47 EST 2002 | davef
First, an earlier poster suggested using DI water. We are NOT excited about DI water with a NC fluxer, unless DI water is the proper flux thinner. Second, as you inplied, the maintenance steps you take should vary according to the amount of time th
Electronics Forum | Thu May 21 09:54:07 EDT 1998 | Justin Medernach
| I'm reviewing my board fab spec. It calls for a minimum SnPb thickness of 50 microinches on HASL PWB's. I've looked at other specs that call out anything from 30 to 80 microinches, and others that just say the copper pad must be covered and solde
Electronics Forum | Tue May 26 14:50:07 EDT 1998 | Dave F
| | I'm reviewing my board fab spec. It calls for a minimum SnPb thickness of 50 microinches on HASL PWB's. I've looked at other specs that call out anything from 30 to 80 microinches, and others that just say the copper pad must be covered and sol
