Electronics Forum | Fri Feb 20 08:44:05 EST 2004 | davef
Lucky guess, eh? [Sorry to blow your theory on bad parts] A 1000 of these boards on the line, ummm. Two ideas to consider: * Increase the conveyor angle [don't get carried away, just keep the angle below 8*]. * Balance the flow of solder so that th
Electronics Forum | Tue Jun 14 07:29:12 EDT 2005 | jdumont
So I set up a board yesterday and did a test run. It appears that the spacing does matter on my machine. It placed the part off-center the same amount as one of the fiducials. Im going to look more into fixturing and placement pressure adjustments I
Electronics Forum | Fri Mar 24 14:06:07 EST 2006 | mdemos1
Hi. We are designing in a 128 pin LQFP that has a heat sink in the center of the package. The size of this is 7.44 by 7.55 mm. Can anyone recommend what pad size should be on the board for this? How about stencil aperture/pattern? Thanks, Mike.
Electronics Forum | Tue Apr 25 14:32:18 EDT 2006 | slthomas
Hoss, that's what we do here. Slotted Durastone bars is all it takes unless the board is big enough to require a center support
Electronics Forum | Sat Aug 29 18:12:25 EDT 2009 | gsala
V-Score, few interesting references http://www.vscore.biz/vsguide.html http://coretec-inc.org/files/Technology_Center/Scoring_Process.pdf regards
Electronics Forum | Fri Sep 10 17:18:10 EDT 2010 | spitkis2
They may be misaligned so much so that self centering would not occur. How are you placing the micro BGA's? Depending on how the boards are transported onto the oven's conveyer, by the time they start to go through the oven, there could be additio
Electronics Forum | Mon May 14 16:36:58 EDT 2012 | davef
You're thinking correctly in trying to improve your process. Can you change to a more active flux? Look at the copper that connects to the center pin. You may need to relay-out the board to add a wagon wheel style thermal relief in that area.
Electronics Forum | Wed Mar 06 10:29:40 EST 2013 | sara_pcb
What is the minimum solder mask thickness required for Class 3 products. We are insisting fabricator of the pcb shop to use only spray coated solder mask. The SM thickness on the epoxy is about 17 microns, In the center of the tracks are 8 microns an
Electronics Forum | Mon Dec 06 17:17:57 EST 1999 | Brian W.
I have not used a vision inspection system for this. We used a digital x-y coordinate measurement system. With this, we could find the center of the part and then measure where it was in relation to a fixed point, like a fiducial. Some of the syst
Electronics Forum | Mon Feb 16 01:26:30 EST 2004 | Frank
The 575 was based on the 570 machine. The 570 was Juki's first laser centered machine. It can do 0402 and ICs with a pitch of 0.65mm or greater. The 575, was a re-vamped 570 that Zevatech came up with. Juki played no part in the 575. Zevatech ad
