Electronics Forum | Mon Dec 13 19:34:09 EST 1999 | Steve Thomas
Thanks, gentlemen. All points well taken, and some hit pretty close to home. Our pick-and-place programmer assures me that coplanarity isn't the issue because the machine won't (or can't) place parts beyond an acceptable criteria. It's an Amistar
Electronics Forum | Wed Mar 20 11:47:06 EST 2002 | Hussman
Ron, Some places want/need oven calibration and some don't, just need a profile. I've worked for both. If you need oven calibration, an easy, inexpensive way is to parallel thermalcouple wire to your existing thermalcouples. Terminate the ends of
Electronics Forum | Tue Mar 06 15:59:33 EST 2007 | pima
hello I would like to ask you for advise. I have problem with one of my SMT line and skewed parts at the end of line after reflow. My line is composed: DEK, 3d visual inspection of paste printing, IP3, 8 zones reflow oven. I m builidng there produc
Electronics Forum | Tue Oct 30 18:43:31 EST 2001 | mparker
My first thought is board warp. This is something you can't see when the board is in a reflow oven. I see it occasionally going through wave solder. You may need a pallet with hold down clamps for reflow. Try putting a bare board in a baking oven at
Electronics Forum | Wed Jul 28 00:13:03 EDT 2004 | NTV
We are seeing un-Reflowed paste along the IC > leads. There is only a very small amount imbedded > in the flux, typically there is about 10 beads > per lead. But on most leads. We are using > no-clean Kester 256 paste (Easy Profile)We have > not
Electronics Forum | Thu Jun 25 09:37:48 EDT 1998 | Russ Miculich
The real causes of microcracking are not normally due to pick and place - particularly if you are using a piece of equipment with vacuum pick up and release. The real cause of microcracking is due to thermal stresses on the die and the choice of the
Electronics Forum | Mon Aug 21 20:17:08 EDT 2000 | Dave F
Hey Gyver: Oooow, using a pencil eraser has to take time. I would hate to be the person responding to your customer trying to explain the pencil eraser shreds accidentally left on the board. Awww, just spritz it with DI water and wipe it off with
Electronics Forum | Fri May 29 08:25:13 EDT 2009 | floydf
We are getting what looks like cold solder joints on one of our boards. The boards have an aluminum substrate, and use OSP plating. The solder is lead free - 96.5 Sn, 3.0 Ag, .5 Cu. The flux is no clean. When we first had the problem, my solder profi
Electronics Forum | Sun Oct 10 17:40:50 EDT 1999 | JohnW
| | | Is there an IPC Standard stating the max. number of times that a PCB can pass through a reflow or wavesolder machine without having solder mask breakdown. | | | | | | PCB is FR4 | | | Solder Mask is LPI | | | Reflow and W/S Profile = Standard
Electronics Forum | Fri Jun 20 18:32:55 EDT 2008 | hegemon
Back when I used to do a lot of these style devices we ran into the same problem you are describing. Use a pattern for the center pad area and keep the total coverage to about 68% of the pad area. Diagonal Stripes, tic tac toe, cloverleaf, dot array
