Electronics Forum | Tue Apr 24 18:21:30 EDT 2007 | flipit
Hi, The verbiage states lead finish on components and not solder used in assembly. I have found nothing that states that Swatch got an exemption. Although the 650 micron pitch spec seems to have come from the data Swatch presented in their execpti
Electronics Forum | Fri Jun 08 11:35:16 EDT 2007 | patrickbruneel
80-90% of an average SM component is non wetable (pushing away solder). So if you would use a single smooth lambda wave (massive amount of molten metal) the negative force of the non-wetable part of the component would be so high that the solder wou
Electronics Forum | Mon Nov 05 16:54:00 EST 2007 | bbarton
There are several things that can be done to increase throughput on you screen printer, including the panelization of your bords as Steve & Hussman has pointed out. However that's of limited use if you have plenty of stock that is not panelized. That
Electronics Forum | Fri Nov 23 16:32:05 EST 2007 | davef
There a several things you can do to prevent the solder wicking down the hole with the current design, and that's where you should focus. Cost goes up as you go down the list, but in neither case do you need to respin the board, have solder starvatio
Electronics Forum | Thu Nov 29 15:52:53 EST 2007 | jmelson
Some other machines are a lot simpler. Here's how the Philips (mady by Yamaha) CSM84 works. Smaller tape (8 and 12 mm) feeders are all mechanical. A plunger on the head pushes a lever on the feeder at the same time the head comes down. First, the
Electronics Forum | Mon Apr 14 19:26:35 EDT 2008 | diesel_1t
Update: Recently, we ran a (old) product on which they made a new stencil, appertures 1-1 on 0603. As soon as they began to run, tombstones appear. I went to trashcan to rescue old stencil, and noticed that pads came with a "c" shape reduction, I as
Electronics Forum | Tue May 13 08:26:29 EDT 2008 | davef
First, on your reflow temperature comment: The 183*C focus for reflow recipes for tin-lead solder is a falicy. If you held a recipe for tin-lead solder at 183*C peak, it would never reflow. Recipes for tin-lead solder need to be at liquidus plus 20*C
Electronics Forum | Wed May 14 12:42:16 EDT 2008 | rgduval
Dave, Realized I didn't respond to one of your questions. We pasted and reflowed one board, with no components. This board exhibited extreme dewetting on all pads. The board was LF-HASL, and the paste was Qualitek (which we've used for approximat
Electronics Forum | Mon Jul 21 19:04:34 EDT 2008 | jmelson
I've been using E-teknet for the last couple years, for a wide range of boards from 2 to 6 layers, and one of the 6-layer boards has an insane density and a zillion close-packed vias. Sam at E-teknet guided me through tuning the board design to opti
Electronics Forum | Wed Aug 13 05:18:40 EDT 2008 | lococost
that's a pretty cool idea, I like some thinking 'outside the box '! 1. I don't think picking it up and placing it will be much of a problem. once the rivet is placed it will be held in place by the paste. However, you would need to make a tray that
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