Electronics Forum | Fri Mar 10 12:12:55 EST 2000 | Russ
Casey, I will start with the lack of thermo-couple control - The unit I have is based on time and temp. exclusively. What happens when a cold board gets reworked vs. a hot board? No bottom side preheat, the heating is very localized to topside a
Electronics Forum | Fri Dec 08 11:08:03 EST 2000 | Antonio
Ok fellas, tell me how you'd fix this! I'm having melf connectors that are tombstoning in the wave, NOT the reflow, the wave. I've never seen this before. All other parameters are the same...solder, preheats, placements, the board, building humidi
Electronics Forum | Fri Dec 08 23:02:24 EST 2000 | LeeKibler
Beware the foam fluxer. I had a problem with cracked caps that just about drove me off the deep end. I discovered that my foam fluxer air knife was not turned on resulting in excessive flux. The excessive flux (VOC free) was not properly dried off
Electronics Forum | Tue Oct 17 12:15:19 EDT 2000 | NLykus
Dave, Current process is Insert through hole components topside Dispense SMT glue Place SMT components bottom side Glue cure Insert 1 through hole component by hand Wave Wave temperature is 480oF Topside preheats in D.O.E ranged from 99oc to 108oC
Electronics Forum | Wed Oct 11 10:29:28 EDT 2000 | G. English
Try the following steps : FIRST CHECK THE ARCHIVE for further information, it WILL help you. Step One : What�s the chemical analysis of this white res? Obtain a sample. It could be tin, rosin, or something else??? Step Two : The fastest way I know
Electronics Forum | Thu Oct 05 11:10:23 EDT 2000 | Wolfgang Busko
It�s funny, the third question on this topic via "Georgia tech..." in the last few weeks. Seems on that particular forum people with the same interests are gathering or maybe they are working all on the problem without knowing about each other. Dani
Electronics Forum | Thu Aug 17 08:44:14 EDT 2000 | Wolfgang Busko
Hi Jaqueline, my first thought goes into the same direction, twist or warp (either the board or the BGA itself). I don�t know the SRT equipment. I�ve noticed with our equipment using a spot underheat element caused some warpage of the PCB making it
Electronics Forum | Thu Jul 27 12:54:53 EDT 2000 | John Thorup
Hi Jason I think Wolfgang has this one nailed. If it's the same four pins every time and nothing changes this, even rotating the board 90 degrees, then you're probably going to find something like a ground plane connected to them. I don't think sol
Electronics Forum | Fri Jul 28 14:34:13 EDT 2000 | Gary Simbulan
Belive it or not, these boards were run through a Centech batch mode Vapor Phase machine. Single stage top side IR preheat. Vapor temp 218 C. Solder paste is an SN62 RMA.The boards were FR4 8 layer w/ solder mask, fairly conventional as might be e
Electronics Forum | Fri Jul 14 11:34:37 EDT 2000 | Mike F
John, The first thing to check is how tight the boards are being held in the conveyor (assuming you are using a finger conveyor). They should be a little loose at the input end so there is some room to expand. If the boards are held too tightly, when
