Electronics Forum | Thu Oct 30 22:29:58 EDT 2008 | davef
For most applications, a nice square [or rectangle] pad works just fine. Assemblers ship boat loads of boards with these every day. It's reasonable for tight decoupling capacitor requirement applications to use round or radiused pads for components
Electronics Forum | Thu Oct 30 21:06:20 EDT 2008 | ashley
Hello mickd, For Fuji practice, the primary tooling hole preferably be 5mm from the edge of the PCB (lower right hand corner). This is the reference X0, Y0 co-ordinates in the Fuji program where placing co-ordinates going LEFT will be -ve value & go
Electronics Forum | Fri Oct 31 18:08:34 EDT 2008 | m79d
thank you both for the input ok so i understand the hole is on a 5mmx5mm center the pin seems to be 3mm. About 3mm of the board goes under the clamp rail so the tooling strip must be wider than 5mm as the fiducial also needs to be on it. Mark_m yo
Electronics Forum | Tue Nov 04 07:50:14 EST 2008 | davef
Sure. Here's what you should do to apply repeatable amounts of flux on BGA during rework: * Squirt some gel flux on a plate or something like that that has a flat bottom and raised sides to corral the flux. * Cut notches into one edge of an old credi
Electronics Forum | Thu Nov 06 09:27:46 EST 2008 | rway
I would rethink your schematic. If you are using D1 for power indication, put D1 in series with a 1KO resistor to ground. D1 will 1.5-2.2V which will your supplies voltage to your 555 timer. What are you driving on the ouput at pin 3? If you ar
Electronics Forum | Wed Nov 05 18:39:06 EST 2008 | joeherz
Hello, We have recently installed a selective soldering machine and are seeing some voiding/cratering in random locations. We have done some basic experimenting with fluxing parameters, preheat and dwell times but haven't been able to eliminate it.
Electronics Forum | Sat Nov 08 09:10:16 EST 2008 | davef
SN100 was designed for selective soldering and producing low levels of voiding. But thin barrel plating is a common cause of voids in wave and selective soldered connections, as you say. As a result, you checked the plating thickness and it was accep
Electronics Forum | Tue Nov 11 19:41:06 EST 2008 | gregoryyork
Thats the problem residual residue from HASL fluxes Lead free especially are worse.Very hygroscopic and out gass and produce dewetting as well over wave soldered boards especially. Leave iron on blown joint and will after several seconds fizz and pop
Electronics Forum | Wed Nov 12 18:58:19 EST 2008 | joeherz
I attended SMTA's copper dissolution webinar this morning and am almost convinced that this is not our problem. Still planning to do cross sections to verify but our dwell times are nowhere near levels that could cause a problem assuming good platin
Electronics Forum | Mon Nov 10 13:27:07 EST 2008 | evtimov
Hi janz, you should be aware of everything. You are going to change subsystem on your machine. How much vacuum you need on the machine? Can you control the vacuum level with your system? Can you control the the system at all? Is it really much more
