Electronics Forum | Wed Apr 10 11:45:08 EDT 2002 | mwoodall
We measure the thickness of solder paste printed onto PCBs as a control of the printing process. Generally 6 thou stencils are used and give between 6.2 and 6.8 thou. What thicknesses do other users get? Cheers! Mark
Electronics Forum | Wed Apr 10 13:20:36 EDT 2002 | barryg
I am curious how you measure your printed paste thickness. We are considering doing the same. As it is now we assure we have squeegee pressure and speed controlled, have not actually measure the printed paste thickness.
Electronics Forum | Wed Apr 10 22:35:59 EDT 2002 | davef
How do you assure you "have squeegee pressure and speed controlled"? Search the fine SMTnet Archives for background on measuring paste thickness.
Electronics Forum | Fri May 10 17:50:25 EDT 2002 | davef
We chart the following: * Reflow: Time over liquidous +25�C * Wave: Contact time and track tin, copper, gold, and antimony in pot analysis.
Electronics Forum | Wed May 22 12:17:08 EDT 2002 | timdaly
Change over and flexibility are two critical areas you need to have controlled in order to be successful in the high mix, low volume market. Machines to consider: SAMSUNG CP series, MyData My series, and Europlacers.
Electronics Forum | Thu Jun 06 09:46:28 EDT 2002 | davef
Most paste supplier recommendations seem to work fine in the locale of the printer. Search the fine SMTnet Archives for recommendations on the range of control for temperature and humidity in a assembly shop.
Electronics Forum | Tue Jul 02 07:11:31 EDT 2002 | davef
There is nothing inherently wrong with voids in solder connections. They: * Do indicate that the reflow soldering process is not well controlled. * Can comprise the strength of the solder connection. Look here: http://www.smtinfocus.com/smt_failure
Electronics Forum | Wed Sep 11 13:20:37 EDT 2002 | stepheno
I've seen this problem caused by the cool down. On a 7 zone oven I made a profile to peak at zone 5 to give some semblance of control to the cool down. The component can develope a big delta T, because of the difference of materials
Electronics Forum | Fri Oct 25 04:06:56 EDT 2002 | kcngoi
Hi Adam, Excessive heat from soldering iron will left the burn mark of RMA flux. The residue is hard to remove. Suggest to use the Flux pen for better control.
Electronics Forum | Fri Jul 18 10:11:23 EDT 2003 | James
Just got a demo in for a VTECH 250+, it is fast and easy to use. I have tried others but nothing beats this one. Great buy for using for inventory control.
